bring back islocal check

fix onboarding fn
fix(desktop): gate first launch onboarding
2026-07-03 00:12:36 +08:00 · 2026-07-02 22:06:43 +08:00 · 2026-07-02 21:42:36 +08:00 · 2026-07-02 16:44:47 +08:00 · 2026-07-02 04:39:49 +00:00 · 2026-07-02 04:25:52 +00:00
744 changed files with 35079 additions and 12737 deletions
@@ -34,10 +34,48 @@ jobs:

            const now = Date.now();
            const twoHours = 2 * 60 * 60 * 1000;
+            const orgMemberAssociations = new Set(['OWNER', 'MEMBER']);
+            const agentLogin = 'opencode-agent[bot]';
+            const { data: file } = await github.rest.repos.getContent({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              path: '.github/TEAM_MEMBERS',
+              ref: 'dev',
+            });
+            const teamMembers = new Set(
+              Buffer.from(file.content, 'base64')
+                .toString()
+                .split('\n')
+                .map((line) => line.trim().toLowerCase())
+                .filter(Boolean)
+            );
+
+            function isExempt(item) {
+              const login = item.user?.login?.toLowerCase();
+              return (
+                login === agentLogin ||
+                orgMemberAssociations.has(item.author_association) ||
+                (login && teamMembers.has(login))
+              );
+            }

            for (const item of items) {
              const isPR = !!item.pull_request;
              const kind = isPR ? 'PR' : 'issue';
+              const login = item.user?.login;
+
+              if (isExempt(item)) {
+                core.info(`Skipping ${kind} #${item.number}; author ${login || 'unknown'} is exempt`);
+                try {
+                  await github.rest.issues.removeLabel({
+                    owner: context.repo.owner,
+                    repo: context.repo.repo,
+                    issue_number: item.number,
+                    name: 'needs:compliance',
+                  });
+                } catch (e) {}
+                continue;
+              }

              const { data: comments } = await github.rest.issues.listComments({
                owner: context.repo.owner,
@@ -17,12 +17,31 @@ jobs:
        with:
          fetch-depth: 1

+      - name: Check exempt issue author
+        id: author
+        run: |
+          LOGIN="${{ github.event.issue.user.login }}"
+          ASSOCIATION="${{ github.event.issue.author_association }}"
+
+          if [ "$LOGIN" = "opencode-agent[bot]" ] ||
+             [ "$ASSOCIATION" = "OWNER" ] ||
+             [ "$ASSOCIATION" = "MEMBER" ] ||
+             grep -qxiF "$LOGIN" .github/TEAM_MEMBERS; then
+            echo "skip=true" >> "$GITHUB_OUTPUT"
+            echo "Skipping issue automation for exempt author: $LOGIN ($ASSOCIATION)"
+          else
+            echo "skip=false" >> "$GITHUB_OUTPUT"
+          fi
+
      - uses: ./.github/actions/setup-bun
+        if: steps.author.outputs.skip != 'true'

      - name: Install opencode
+        if: steps.author.outputs.skip != 'true'
        run: curl -fsSL https://opencode.ai/install | bash

      - name: Check duplicates and compliance
+        if: steps.author.outputs.skip != 'true'
        env:
          OPENCODE_API_KEY: ${{ secrets.OPENCODE_API_KEY }}
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -38,6 +57,7 @@ jobs:
          opencode run -m opencode/claude-sonnet-4-6 "A new issue has been created:

          Issue number: ${{ github.event.issue.number }}
+          Issue author association: ${{ github.event.issue.author_association }}

          Lookup this issue with gh issue view ${{ github.event.issue.number }}.

@@ -49,6 +69,8 @@ jobs:

          Check whether the issue follows our contributing guidelines and issue templates.

+          If the issue author association is OWNER or MEMBER, skip this compliance check. Do not add the needs:compliance label for organization-owned issues.
+
          This project has three issue templates that every issue MUST use one of:

          1. Bug Report - requires a Description field with real content
@@ -83,7 +105,7 @@ jobs:

          Based on your findings, post a SINGLE comment on issue #${{ github.event.issue.number }}. Build the comment as follows:

-          If the issue is NOT compliant, start the comment with:
+          If the issue is NOT compliant and the author association is not OWNER or MEMBER, start the comment with:
          <!-- issue-compliance -->
          Then explain what needs to be fixed and that they have 2 hours to edit the issue before it is automatically closed. Also add the label needs:compliance to the issue using: gh issue edit ${{ github.event.issue.number }} --add-label needs:compliance

@@ -129,12 +151,31 @@ jobs:
        with:
          fetch-depth: 1

+      - name: Check exempt issue author
+        id: author
+        run: |
+          LOGIN="${{ github.event.issue.user.login }}"
+          ASSOCIATION="${{ github.event.issue.author_association }}"
+
+          if [ "$LOGIN" = "opencode-agent[bot]" ] ||
+             [ "$ASSOCIATION" = "OWNER" ] ||
+             [ "$ASSOCIATION" = "MEMBER" ] ||
+             grep -qxiF "$LOGIN" .github/TEAM_MEMBERS; then
+            echo "skip=true" >> "$GITHUB_OUTPUT"
+            echo "Skipping issue automation for exempt author: $LOGIN ($ASSOCIATION)"
+          else
+            echo "skip=false" >> "$GITHUB_OUTPUT"
+          fi
+
      - uses: ./.github/actions/setup-bun
+        if: steps.author.outputs.skip != 'true'

      - name: Install opencode
+        if: steps.author.outputs.skip != 'true'
        run: curl -fsSL https://opencode.ai/install | bash

      - name: Recheck compliance
+        if: steps.author.outputs.skip != 'true'
        env:
          OPENCODE_API_KEY: ${{ secrets.OPENCODE_API_KEY }}
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -148,9 +189,12 @@ jobs:
            }
        run: |
          opencode run -m opencode/claude-sonnet-4-6 "Issue #${{ github.event.issue.number }} was previously flagged as non-compliant and has been edited.
+          Issue author association: ${{ github.event.issue.author_association }}

          Lookup this issue with gh issue view ${{ github.event.issue.number }}.

+          If the issue author association is OWNER or MEMBER, remove the needs:compliance label if present, delete the previous compliance comment if present, and do not post a new comment.
+
          Re-check whether the issue now follows our contributing guidelines and issue templates.

          This project has three issue templates that every issue MUST use one of:
@@ -16,13 +16,32 @@ jobs:
        with:
          fetch-depth: 1

+      - name: Check exempt issue author
+        id: author
+        run: |
+          LOGIN="${{ github.event.issue.user.login }}"
+          ASSOCIATION="${{ github.event.issue.author_association }}"
+
+          if [ "$LOGIN" = "opencode-agent[bot]" ] ||
+             [ "$ASSOCIATION" = "OWNER" ] ||
+             [ "$ASSOCIATION" = "MEMBER" ] ||
+             grep -qxiF "$LOGIN" .github/TEAM_MEMBERS; then
+            echo "skip=true" >> "$GITHUB_OUTPUT"
+            echo "Skipping issue automation for exempt author: $LOGIN ($ASSOCIATION)"
+          else
+            echo "skip=false" >> "$GITHUB_OUTPUT"
+          fi
+
      - name: Setup Bun
+        if: steps.author.outputs.skip != 'true'
        uses: ./.github/actions/setup-bun

      - name: Install opencode
+        if: steps.author.outputs.skip != 'true'
        run: curl -fsSL https://opencode.ai/install | bash

      - name: Triage issue
+        if: steps.author.outputs.skip != 'true'
        env:
          OPENCODE_API_KEY: ${{ secrets.OPENCODE_API_KEY }}
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
@@ -29,7 +29,7 @@
    },
    "packages/app": {
      "name": "@opencode-ai/app",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@dnd-kit/abstract": "0.5.0",
        "@dnd-kit/dom": "0.5.0",
@@ -37,6 +37,7 @@
        "@dnd-kit/solid": "0.5.0",
        "@kobalte/core": "catalog:",
        "@opencode-ai/core": "workspace:*",
+        "@opencode-ai/schema": "workspace:*",
        "@opencode-ai/sdk": "workspace:*",
        "@opencode-ai/session-ui": "workspace:*",
        "@opencode-ai/ui": "workspace:*",
@@ -83,6 +84,7 @@
        "@types/luxon": "catalog:",
        "@types/node": "catalog:",
        "@typescript/native-preview": "catalog:",
+        "tw-animate-css": "1.4.0",
        "typescript": "catalog:",
        "vite": "catalog:",
        "vite-plugin-icons-spritesheet": "3.0.1",
@@ -91,7 +93,7 @@
    },
    "packages/cli": {
      "name": "@opencode-ai/cli",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "bin": {
        "lildax": "./bin/lildax.cjs",
      },
@@ -139,7 +141,7 @@
    },
    "packages/console/app": {
      "name": "@opencode-ai/console-app",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@cloudflare/vite-plugin": "1.15.2",
        "@ibm/plex": "6.4.1",
@@ -175,7 +177,7 @@
    },
    "packages/console/core": {
      "name": "@opencode-ai/console-core",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@aws-sdk/client-sts": "3.782.0",
        "@jsx-email/render": "1.1.1",
@@ -202,7 +204,7 @@
    },
    "packages/console/function": {
      "name": "@opencode-ai/console-function",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@ai-sdk/anthropic": "3.0.82",
        "@ai-sdk/openai": "3.0.48",
@@ -224,7 +226,7 @@
    },
    "packages/console/mail": {
      "name": "@opencode-ai/console-mail",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@jsx-email/all": "2.2.3",
        "@jsx-email/cli": "1.4.3",
@@ -248,7 +250,7 @@
    },
    "packages/console/support": {
      "name": "@opencode-ai/console-support",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@cloudflare/vite-plugin": "1.15.2",
        "@opencode-ai/console-core": "workspace:*",
@@ -268,7 +270,7 @@
    },
    "packages/core": {
      "name": "@opencode-ai/core",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "bin": {
        "opencode": "./bin/opencode",
      },
@@ -316,10 +318,11 @@
        "ai-gateway-provider": "3.1.2",
        "bun-pty": "0.4.8",
        "cross-spawn": "catalog:",
+        "diff": "catalog:",
        "drizzle-orm": "catalog:",
        "effect": "catalog:",
        "fuzzysort": "3.1.0",
-        "gitlab-ai-provider": "6.9.3",
+        "gitlab-ai-provider": "6.10.0",
        "glob": "13.0.5",
        "google-auth-library": "10.5.0",
        "gray-matter": "4.0.3",
@@ -332,7 +335,7 @@
        "npm-package-arg": "13.0.2",
        "semver": "^7.6.3",
        "turndown": "7.2.0",
-        "venice-ai-sdk-provider": "2.0.2",
+        "venice-ai-sdk-provider": "2.1.1",
        "which": "6.0.1",
        "xdg-basedir": "5.1.0",
        "zod": "catalog:",
@@ -361,7 +364,7 @@
    },
    "packages/desktop": {
      "name": "@opencode-ai/desktop",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@zip.js/zip.js": "2.7.62",
        "effect": "catalog:",
@@ -415,7 +418,7 @@
    },
    "packages/effect-drizzle-sqlite": {
      "name": "@opencode-ai/effect-drizzle-sqlite",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "drizzle-orm": "catalog:",
        "effect": "catalog:",
@@ -429,7 +432,7 @@
    },
    "packages/effect-sqlite-node": {
      "name": "@opencode-ai/effect-sqlite-node",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "effect": "catalog:",
      },
@@ -441,7 +444,7 @@
    },
    "packages/enterprise": {
      "name": "@opencode-ai/enterprise",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@hono/standard-validator": "catalog:",
        "@opencode-ai/core": "workspace:*",
@@ -473,7 +476,7 @@
    },
    "packages/function": {
      "name": "@opencode-ai/function",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@octokit/auth-app": "8.0.1",
        "@octokit/rest": "catalog:",
@@ -489,7 +492,7 @@
    },
    "packages/http-recorder": {
      "name": "@opencode-ai/http-recorder",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@effect/platform-node": "4.0.0-beta.83",
        "@effect/platform-node-shared": "4.0.0-beta.83",
@@ -520,7 +523,7 @@
    },
    "packages/llm": {
      "name": "@opencode-ai/llm",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@opencode-ai/schema": "workspace:*",
        "@smithy/eventstream-codec": "4.2.14",
@@ -539,7 +542,7 @@
    },
    "packages/opencode": {
      "name": "opencode",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "bin": {
        "opencode": "./bin/opencode",
      },
@@ -551,7 +554,7 @@
        "@ai-sdk/amazon-bedrock": "4.0.112",
        "@ai-sdk/anthropic": "3.0.82",
        "@ai-sdk/azure": "3.0.49",
-        "@ai-sdk/cerebras": "2.0.41",
+        "@ai-sdk/cerebras": "2.0.60",
        "@ai-sdk/cohere": "3.0.27",
        "@ai-sdk/deepinfra": "2.0.41",
        "@ai-sdk/gateway": "3.0.104",
@@ -611,7 +614,7 @@
        "drizzle-orm": "catalog:",
        "effect": "catalog:",
        "fuzzysort": "3.1.0",
-        "gitlab-ai-provider": "6.9.3",
+        "gitlab-ai-provider": "6.10.0",
        "glob": "13.0.5",
        "google-auth-library": "10.5.0",
        "gray-matter": "4.0.3",
@@ -635,7 +638,7 @@
        "tree-sitter-powershell": "0.25.10",
        "turndown": "7.2.0",
        "ulid": "catalog:",
-        "venice-ai-sdk-provider": "2.0.2",
+        "venice-ai-sdk-provider": "2.1.1",
        "vscode-jsonrpc": "8.2.1",
        "web-tree-sitter": "0.25.10",
        "ws": "8.21.0",
@@ -669,7 +672,7 @@
    },
    "packages/plugin": {
      "name": "@opencode-ai/plugin",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@ai-sdk/provider": "3.0.8",
        "@opencode-ai/sdk": "workspace:*",
@@ -745,7 +748,7 @@
    },
    "packages/sdk/js": {
      "name": "@opencode-ai/sdk",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "cross-spawn": "catalog:",
      },
@@ -760,7 +763,7 @@
    },
    "packages/server": {
      "name": "@opencode-ai/server",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@opencode-ai/core": "workspace:*",
        "@opencode-ai/protocol": "workspace:*",
@@ -775,7 +778,7 @@
    },
    "packages/session-ui": {
      "name": "@opencode-ai/session-ui",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@kobalte/core": "catalog:",
        "@opencode-ai/core": "workspace:*",
@@ -819,7 +822,7 @@
    },
    "packages/slack": {
      "name": "@opencode-ai/slack",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@opencode-ai/sdk": "workspace:*",
        "@slack/bolt": "^3.17.1",
@@ -832,7 +835,7 @@
    },
    "packages/stats/app": {
      "name": "@opencode-ai/stats-app",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@ibm/plex": "6.4.1",
        "@opencode-ai/stats-core": "workspace:*",
@@ -865,7 +868,7 @@
    },
    "packages/stats/core": {
      "name": "@opencode-ai/stats-core",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@aws-sdk/client-athena": "3.933.0",
        "@planetscale/database": "1.19.0",
@@ -884,7 +887,7 @@
    },
    "packages/stats/server": {
      "name": "@opencode-ai/stats-server",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@aws-sdk/client-firehose": "3.933.0",
        "@effect/platform-node": "catalog:",
@@ -925,7 +928,7 @@
    },
    "packages/tui": {
      "name": "@opencode-ai/tui",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@opencode-ai/core": "workspace:*",
        "@opencode-ai/plugin": "workspace:*",
@@ -952,7 +955,7 @@
    },
    "packages/ui": {
      "name": "@opencode-ai/ui",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@kobalte/core": "catalog:",
        "@pierre/diffs": "catalog:",
@@ -990,6 +993,7 @@
        "@typescript/native-preview": "catalog:",
        "solid-js": "catalog:",
        "tailwindcss": "catalog:",
+        "tw-animate-css": "1.4.0",
        "typescript": "catalog:",
        "vite": "catalog:",
        "vite-plugin-icons-spritesheet": "3.0.1",
@@ -1002,7 +1006,7 @@
    },
    "packages/web": {
      "name": "@opencode-ai/web",
-      "version": "1.17.11",
+      "version": "1.17.13",
      "dependencies": {
        "@astrojs/cloudflare": "12.6.3",
        "@astrojs/markdown-remark": "6.3.1",
@@ -1048,6 +1052,7 @@
    "@modelcontextprotocol/sdk@1.29.0": "patches/@modelcontextprotocol%2Fsdk@1.29.0.patch",
    "gcp-metadata@8.1.2": "patches/gcp-metadata@8.1.2.patch",
    "@standard-community/standard-openapi@0.2.9": "patches/@standard-community%2Fstandard-openapi@0.2.9.patch",
+    "effect@4.0.0-beta.83": "patches/effect@4.0.0-beta.83.patch",
    "@npmcli/agent@4.0.2": "patches/@npmcli%2Fagent@4.0.2.patch",
    "@silvia-odwyer/photon-node@0.3.4": "patches/@silvia-odwyer%2Fphoton-node@0.3.4.patch",
    "@tanstack/solid-virtual@3.13.28": "patches/@tanstack%2Fsolid-virtual@3.13.28.patch",
@@ -3807,7 +3812,7 @@

    "github-slugger": ["github-slugger@2.0.0", "", {}, "sha512-IaOQ9puYtjrkq7Y0Ygl9KDZnrf/aiUJYUpVf89y8kyaxbRG7Y1SrX/jaumrv81vc61+kiMempujsM3Yw7w5qcw=="],

-    "gitlab-ai-provider": ["gitlab-ai-provider@6.9.3", "", { "dependencies": { "@anthropic-ai/sdk": "^0.71.0", "@anycable/core": "^0.9.2", "graphql-request": "^6.1.0", "isomorphic-ws": "^5.0.0", "openai": "^6.16.0", "socket.io-client": "^4.8.1", "vscode-jsonrpc": "^8.2.1", "zod": "^3.25.76" }, "peerDependencies": { "@ai-sdk/provider": ">=3.0.0", "@ai-sdk/provider-utils": ">=4.0.0" } }, "sha512-lWo6b6es5+k9iXaDIvE9ECzyK4zfEza4+dQ5FN8SJpEuVRi3ZBCpHIOTa32QoYEDCBaiPh+tcyca86PfNodmlg=="],
+    "gitlab-ai-provider": ["gitlab-ai-provider@6.10.0", "", { "dependencies": { "@anthropic-ai/sdk": "^0.71.0", "@anycable/core": "^0.9.2", "graphql-request": "^6.1.0", "isomorphic-ws": "^5.0.0", "openai": "^6.16.0", "socket.io-client": "^4.8.1", "vscode-jsonrpc": "^8.2.1", "zod": "^3.25.76" }, "peerDependencies": { "@ai-sdk/provider": ">=3.0.0", "@ai-sdk/provider-utils": ">=4.0.0" } }, "sha512-oWEZ06rDO6JjB7INHO882wyBAQqCZVHiDHwCs5M+VPmdDj8TzhGXcYesA2CcV5RoI5lfHLKwGp5uKFB62VWpqw=="],

    "glob": ["glob@13.0.5", "", { "dependencies": { "minimatch": "^10.2.1", "minipass": "^7.1.2", "path-scurry": "^2.0.0" } }, "sha512-BzXxZg24Ibra1pbQ/zE7Kys4Ua1ks7Bn6pKLkVPZ9FZe4JQS6/Q7ef3LG1H+k7lUf5l4T3PLSyYyYJVYUvfgTw=="],

@@ -5315,6 +5320,8 @@

    "turndown": ["turndown@7.2.0", "", { "dependencies": { "@mixmark-io/domino": "^2.2.0" } }, "sha512-eCZGBN4nNNqM9Owkv9HAtWRYfLA4h909E/WGAWWBpmB275ehNhZyk87/Tpvjbp0jjNl9XwCsbe6bm6CqFsgD+A=="],

+    "tw-animate-css": ["tw-animate-css@1.4.0", "", {}, "sha512-7bziOlRqH0hJx80h/3mbicLW7o8qLsH5+RaLR2t+OHM3D0JlWGODQKQ4cxbK7WlvmUxpcj6Kgu6EKqjrGFe3QQ=="],
+
    "tw-to-css": ["tw-to-css@0.0.12", "", { "dependencies": { "postcss": "8.4.31", "postcss-css-variables": "0.18.0", "tailwindcss": "3.3.2" } }, "sha512-rQAsQvOtV1lBkyCw+iypMygNHrShYAItES5r8fMsrhhaj5qrV2LkZyXc8ccEH+u5bFjHjQ9iuxe90I7Kykf6pw=="],

    "type-fest": ["type-fest@4.41.0", "", {}, "sha512-TeTSQ6H5YHvpqVwBRcnLDCBnDOHWYu7IvGbHT6N8AOymcr9PJGjc1GTtiWZTYg0NCgYwvnYWEkVChQAr9bjfwA=="],
@@ -5423,7 +5430,7 @@

    "vary": ["vary@1.1.2", "", {}, "sha512-BNGbWLfd0eUPabhkXUVm0j8uuvREyTh5ovRa/dyow/BqAbZJyC+5fU+IzQOzmAKzYqYRAISoRhdQr3eIZ/PXqg=="],

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+    "venice-ai-sdk-provider": ["venice-ai-sdk-provider@2.1.1", "", { "dependencies": { "@ai-sdk/openai-compatible": "^2.0.51", "@ai-sdk/provider": "^3.0.10", "@ai-sdk/provider-utils": "^4.0.30" }, "peerDependencies": { "ai": "^6.0.90" } }, "sha512-w3OHkuzzKZ3r2TOxER6myBYzZJNoDqol+DUHu3NnfBN/GETnUVxecZJab0CHQQ8GZc0jjzpFymepjcLDPS4SQg=="],

    "verror": ["verror@1.10.1", "", { "dependencies": { "assert-plus": "^1.0.0", "core-util-is": "1.0.2", "extsprintf": "^1.2.0" } }, "sha512-veufcmxri4e3XSrT0xwfUR7kguIkaxBeosDg00yDWhk49wdwkSUrvvsm7nc75e1PUyvIeZj6nS8VQRYz2/S4Xg=="],

@@ -5977,6 +5984,8 @@

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+    "@opencode-ai/core/semver": ["semver@7.8.5", "", { "bin": { "semver": "bin/semver.js" } }, "sha512-Y7/KDsb8LjooZpwaqGyulO6DQlksgCncchHGk+sZIY4SBvUocMBEFH5Ur1fI4dV+Jvl0w6cjvucaIi40puRioA=="],
+
    "@opencode-ai/desktop/@actions/artifact": ["@actions/artifact@4.0.0", "", { "dependencies": { "@actions/core": "^1.10.0", "@actions/github": "^6.0.1", "@actions/http-client": "^2.1.0", "@azure/core-http": "^3.0.5", "@azure/storage-blob": "^12.15.0", "@octokit/core": "^5.2.1", "@octokit/plugin-request-log": "^1.0.4", "@octokit/plugin-retry": "^3.0.9", "@octokit/request": "^8.4.1", "@octokit/request-error": "^5.1.1", "@protobuf-ts/plugin": "^2.2.3-alpha.1", "archiver": "^7.0.1", "jwt-decode": "^3.1.2", "unzip-stream": "^0.3.1" } }, "sha512-HCc2jMJRAfviGFAh0FsOR/jNfWhirxl7W6z8zDtttt0GltwxBLdEIjLiweOPFl9WbyJRW1VWnPUSAixJqcWUMQ=="],

    "@opencode-ai/desktop/marked": ["marked@15.0.12", "", { "bin": { "marked": "bin/marked.js" } }, "sha512-8dD6FusOQSrpv9Z1rdNMdlSgQOIP880DHqnohobOmYLElGEqAL/JvxvuxZO16r4HtjTlfPRDC1hbvxC9dPN2nA=="],
@@ -5987,6 +5996,8 @@

    "@opencode-ai/llm/@smithy/util-utf8": ["@smithy/util-utf8@4.2.2", "", { "dependencies": { "@smithy/util-buffer-from": "^4.2.2", "tslib": "^2.6.2" } }, "sha512-75MeYpjdWRe8M5E3AW0O4Cx3UadweS+cwdXjwYGBW5h/gxxnbeZ877sLPX/ZJA9GVTlL/qG0dXP29JWFCD1Ayw=="],

+    "@opencode-ai/script/semver": ["semver@7.8.5", "", { "bin": { "semver": "bin/semver.js" } }, "sha512-Y7/KDsb8LjooZpwaqGyulO6DQlksgCncchHGk+sZIY4SBvUocMBEFH5Ur1fI4dV+Jvl0w6cjvucaIi40puRioA=="],
+
    "@opencode-ai/session-ui/@solid-primitives/resize-observer": ["@solid-primitives/resize-observer@2.1.3", "", { "dependencies": { "@solid-primitives/event-listener": "^2.4.3", "@solid-primitives/rootless": "^1.5.2", "@solid-primitives/static-store": "^0.1.2", "@solid-primitives/utils": "^6.3.2" }, "peerDependencies": { "solid-js": "^1.6.12" } }, "sha512-zBLje5E06TgOg93S7rGPldmhDnouNGhvfZVKOp+oG2XU8snA+GoCSSCz1M+jpNAg5Ek2EakU5UVQqL152WmdXQ=="],

    "@opencode-ai/ui/@solid-primitives/resize-observer": ["@solid-primitives/resize-observer@2.1.3", "", { "dependencies": { "@solid-primitives/event-listener": "^2.4.3", "@solid-primitives/rootless": "^1.5.2", "@solid-primitives/static-store": "^0.1.2", "@solid-primitives/utils": "^6.3.2" }, "peerDependencies": { "solid-js": "^1.6.12" } }, "sha512-zBLje5E06TgOg93S7rGPldmhDnouNGhvfZVKOp+oG2XU8snA+GoCSSCz1M+jpNAg5Ek2EakU5UVQqL152WmdXQ=="],
@@ -6327,6 +6338,8 @@

    "nypm/tinyexec": ["tinyexec@1.2.4", "", {}, "sha512-SHf/r48b7vOrjve9PxJo3MN5v5yuyjHvdUcrQffT3WXMUfnGmHDVbC4k3sHJaJTgZCwpUplIaAo5ANtMyp3YHg=="],

+    "opencode/@ai-sdk/cerebras": ["@ai-sdk/cerebras@2.0.60", "", { "dependencies": { "@ai-sdk/openai-compatible": "2.0.54", "@ai-sdk/provider": "3.0.12", "@ai-sdk/provider-utils": "4.0.33" }, "peerDependencies": { "zod": "^3.25.76 || ^4.1.8" } }, "sha512-Rnok3cThg6awBwaDSyiZpgRpbV7pqxGYrA89LODCo5cuEHeP2h0AM0lLHP7zIkclAdXfOm4wldKi/S2T/DGCOw=="],
+
    "opencode/@ai-sdk/openai": ["@ai-sdk/openai@3.0.53", "", { "dependencies": { "@ai-sdk/provider": "3.0.8", "@ai-sdk/provider-utils": "4.0.23" }, "peerDependencies": { "zod": "^3.25.76 || ^4.1.8" } }, "sha512-Wld+Rbc05KaUn08uBt06eEuwcgalcIFtIl32Yp+GxuZXUQwOb6YeAuq+C6da4ch6BurFoqEaLemJVwjBb7x+PQ=="],

    "opencode/@ai-sdk/openai-compatible": ["@ai-sdk/openai-compatible@2.0.41", "", { "dependencies": { "@ai-sdk/provider": "3.0.8", "@ai-sdk/provider-utils": "4.0.23" }, "peerDependencies": { "zod": "^3.25.76 || ^4.1.8" } }, "sha512-kNAGINk71AlOXx10Dq/PXw4t/9XjdK8uxfpVElRwtSFMdeSiLVt58p9TPx4/FJD+hxZuVhvxYj9r42osxWq79g=="],
@@ -6335,6 +6348,8 @@

    "opencode/minimatch": ["minimatch@10.0.3", "", { "dependencies": { "@isaacs/brace-expansion": "^5.0.0" } }, "sha512-IPZ167aShDZZUMdRk66cyQAW3qr0WzbHkPdMYa8bzZhlHhO3jALbKdxcaak7W9FfT2rZNpQuUu4Od7ILEpXSaw=="],

+    "opencode/semver": ["semver@7.8.5", "", { "bin": { "semver": "bin/semver.js" } }, "sha512-Y7/KDsb8LjooZpwaqGyulO6DQlksgCncchHGk+sZIY4SBvUocMBEFH5Ur1fI4dV+Jvl0w6cjvucaIi40puRioA=="],
+
    "opencode-gitlab-auth/open": ["open@10.2.0", "", { "dependencies": { "default-browser": "^5.2.1", "define-lazy-prop": "^3.0.0", "is-inside-container": "^1.0.0", "wsl-utils": "^0.1.0" } }, "sha512-YgBpdJHPyQ2UE5x+hlSXcnejzAvD0b22U2OuAP+8OnlJT+PjWPxtgmGqKKc+RgTM63U9gN0YzrYc71R2WT/hTA=="],

    "openid-client/jose": ["jose@4.15.9", "", {}, "sha512-1vUQX+IdDMVPj4k8kOxgUqlcK518yluMuGZwqlr44FS1ppZB/5GWh4rZG89erpOBOJjU/OBsnCVFfapsRz6nEA=="],
@@ -6443,11 +6458,11 @@

    "unzipper/fs-extra": ["fs-extra@11.3.5", "", { "dependencies": { "graceful-fs": "^4.2.0", "jsonfile": "^6.0.1", "universalify": "^2.0.0" } }, "sha512-eKpRKAovdpZtR1WopLHxlBWvAgPny3c4gX1G5Jhwmmw4XJj0ifSD5qB5TOo8hmA0wlRKDAOAhEE1yVPgs6Fgcg=="],

-    "venice-ai-sdk-provider/@ai-sdk/openai-compatible": ["@ai-sdk/openai-compatible@2.0.47", "", { "dependencies": { "@ai-sdk/provider": "3.0.10", "@ai-sdk/provider-utils": "4.0.27" }, "peerDependencies": { "zod": "^3.25.76 || ^4.1.8" } }, "sha512-Enm5UlL0zUCrW3792opk5h7hRWxZOZzDe6eQYVFqX9LUOGGCe1h8MZWAGim765nwzgnjlpeYOsuzZmLtRsTPlg=="],
+    "venice-ai-sdk-provider/@ai-sdk/openai-compatible": ["@ai-sdk/openai-compatible@2.0.53", "", { "dependencies": { "@ai-sdk/provider": "3.0.12", "@ai-sdk/provider-utils": "4.0.32" }, "peerDependencies": { "zod": "^3.25.76 || ^4.1.8" } }, "sha512-SoPSkrL5cbNQnAljRsJ7pOzJ2FmWgnhC0lfFOda873ycCdFJL1A+h3Ib7mX2spcv3XnNaO13y/45/0RyqNWlIQ=="],

    "venice-ai-sdk-provider/@ai-sdk/provider": ["@ai-sdk/provider@3.0.10", "", { "dependencies": { "json-schema": "^0.4.0" } }, "sha512-Q3BZ27qfpYqnCYGvE3vt+Qi6LGOF9R5Nmzn+9JoM1lCRsD9mYaIhfJLkSunN48nfGXJ6n+XNV0J/XVpqGQl7Dw=="],

-    "venice-ai-sdk-provider/@ai-sdk/provider-utils": ["@ai-sdk/provider-utils@4.0.27", "", { "dependencies": { "@ai-sdk/provider": "3.0.10", "@standard-schema/spec": "^1.1.0", "eventsource-parser": "^3.0.8" }, "peerDependencies": { "zod": "^3.25.76 || ^4.1.8" } }, "sha512-ubkAJ+xODouwtmN1tYlvTPphH1hPOBfZaEQe8U7skGvFAnIRs9PPpsq57bC2+Ky/MB4yzhd6YOsxTAx9sGpazw=="],
+    "venice-ai-sdk-provider/@ai-sdk/provider-utils": ["@ai-sdk/provider-utils@4.0.32", "", { "dependencies": { "@ai-sdk/provider": "3.0.12", "@standard-schema/spec": "^1.1.0", "eventsource-parser": "^3.0.8" }, "peerDependencies": { "zod": "^3.25.76 || ^4.1.8" } }, "sha512-Kwj499fTcN9bP/AfGoPU7JWIXeP6VZqKI6omsH062c9E2G4gdjeJczkz4z/tYSkzYjLE2AI3DtZbMfs6D7vn2Q=="],

    "verror/core-util-is": ["core-util-is@1.0.2", "", {}, "sha512-3lqz5YjWTYnW6dlDa5TLaTCcShfar1e40rmcJVwCBJC6mWlFuj0eCHIElmG1g5kyuJ/GD+8Wn4FFCcz4gJPfaQ=="],

@@ -7035,6 +7050,12 @@

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+    "opencode/@ai-sdk/cerebras/@ai-sdk/openai-compatible": ["@ai-sdk/openai-compatible@2.0.54", "", { "dependencies": { "@ai-sdk/provider": "3.0.12", "@ai-sdk/provider-utils": "4.0.33" }, "peerDependencies": { "zod": "^3.25.76 || ^4.1.8" } }, "sha512-OyXt0zK8y2/ZIyWlbxTv2r1M7AK227S+Gl4BYOEF42q0wz1n5m4fwR8L4Fy/MQ4Ho6xje47MPsFcRdIqIyP6Rw=="],
+
+    "opencode/@ai-sdk/cerebras/@ai-sdk/provider": ["@ai-sdk/provider@3.0.12", "", { "dependencies": { "json-schema": "^0.4.0" } }, "sha512-sj9DWTJ2Ze0WR9qsiOPqoqzNx3OxL6iMxHImbhvoe9qOspekbzxNDMiJ4TIGfYHYh9w4OmBjz3prvqhzTi96+Q=="],
+
+    "opencode/@ai-sdk/cerebras/@ai-sdk/provider-utils": ["@ai-sdk/provider-utils@4.0.33", "", { "dependencies": { "@ai-sdk/provider": "3.0.12", "@standard-schema/spec": "^1.1.0", "eventsource-parser": "^3.0.8" }, "peerDependencies": { "zod": "^3.25.76 || ^4.1.8" } }, "sha512-nJ0bAfegMAIJtrzMJtbzer1cS3nb7c7DsyU1S4nrPm7ZU0Mn6SBBZv5IGZZGTbpWTJwqKTSPeZJTXalbAxt1BA=="],
+
    "p-locate/p-limit/yocto-queue": ["yocto-queue@0.1.0", "", {}, "sha512-rVksvsnNCdJ/ohGc6xgPwyN8eheCxsiLM8mxuE/t/mOVqJewPuO1miLpTHQiRgTKCLexL4MeAFVagts7HmNZ2Q=="],

    "pkg-dir/find-up/locate-path": ["locate-path@5.0.0", "", { "dependencies": { "p-locate": "^4.1.0" } }, "sha512-t7hw9pI+WvuwNJXwk5zVHpyhIqzg2qTlklJOf0mVxGSbe3Fp2VieZcduNYjaLDoy6p9uGpQEGWG87WpMKlNq8g=="],
@@ -7067,6 +7088,10 @@

    "unzipper/fs-extra/jsonfile": ["jsonfile@6.2.1", "", { "dependencies": { "universalify": "^2.0.0" }, "optionalDependencies": { "graceful-fs": "^4.1.6" } }, "sha512-zwOTdL3rFQ/lRdBnntKVOX6k5cKJwEc1HdilT71BWEu7J41gXIB2MRp+vxduPSwZJPWBxEzv4yH1wYLJGUHX4Q=="],

+    "venice-ai-sdk-provider/@ai-sdk/openai-compatible/@ai-sdk/provider": ["@ai-sdk/provider@3.0.12", "", { "dependencies": { "json-schema": "^0.4.0" } }, "sha512-sj9DWTJ2Ze0WR9qsiOPqoqzNx3OxL6iMxHImbhvoe9qOspekbzxNDMiJ4TIGfYHYh9w4OmBjz3prvqhzTi96+Q=="],
+
+    "venice-ai-sdk-provider/@ai-sdk/provider-utils/@ai-sdk/provider": ["@ai-sdk/provider@3.0.12", "", { "dependencies": { "json-schema": "^0.4.0" } }, "sha512-sj9DWTJ2Ze0WR9qsiOPqoqzNx3OxL6iMxHImbhvoe9qOspekbzxNDMiJ4TIGfYHYh9w4OmBjz3prvqhzTi96+Q=="],
+
    "venice-ai-sdk-provider/@ai-sdk/provider-utils/@standard-schema/spec": ["@standard-schema/spec@1.1.0", "", {}, "sha512-l2aFy5jALhniG5HgqrD6jXLi/rUWrKvqN/qJx6yoJsgKhblVd+iqqU4RCXavm/jPityDo5TCvKMnpjKnOriy0w=="],

    "vitest/@vitest/expect/@standard-schema/spec": ["@standard-schema/spec@1.1.0", "", {}, "sha512-l2aFy5jALhniG5HgqrD6jXLi/rUWrKvqN/qJx6yoJsgKhblVd+iqqU4RCXavm/jPityDo5TCvKMnpjKnOriy0w=="],
@@ -7363,6 +7388,8 @@

    "js-beautify/glob/path-scurry/lru-cache": ["lru-cache@10.4.3", "", {}, "sha512-JNAzZcXrCt42VGLuYz0zfAzDfAvJWW6AfYlDBQyDV5DClI2m5sAmK+OIO7s59XfsRsWHp02jAJrRadPRGTt6SQ=="],

+    "opencode/@ai-sdk/cerebras/@ai-sdk/provider-utils/@standard-schema/spec": ["@standard-schema/spec@1.1.0", "", {}, "sha512-l2aFy5jALhniG5HgqrD6jXLi/rUWrKvqN/qJx6yoJsgKhblVd+iqqU4RCXavm/jPityDo5TCvKMnpjKnOriy0w=="],
+
    "pkg-dir/find-up/locate-path/p-locate": ["p-locate@4.1.0", "", { "dependencies": { "p-limit": "^2.2.0" } }, "sha512-R79ZZ/0wAxKGu3oYMlz8jy/kbhsNrS7SKZ7PxEHBgJ5+F2mtFW2fK2cOtBh1cHYkQsbzFV7I+EoRKe6Yt0oK7A=="],

    "pkg-up/find-up/locate-path/p-locate": ["p-locate@3.0.0", "", { "dependencies": { "p-limit": "^2.0.0" } }, "sha512-x+12w/To+4GFfgJhBEpiDcLozRJGegY+Ei7/z0tSLkMmxGZNybVMSfWj9aJn8Z5Fc7dBUNJOOVgPv2H7IwulSQ=="],
@@ -1,8 +1,8 @@
 {
  "nodeModules": {
-    "x86_64-linux": "sha256-OiWvZ57vuyHwiIKNtW1n1KX+MLmOXVG3x4fLKvUoGQw=",
-    "aarch64-linux": "sha256-RnPLxVEg/UsL5IeIFWmXMSLUOG6rVrajYxhyDYj1vTA=",
-    "aarch64-darwin": "sha256-KPIgcBA0pTFBPrCTSZgIbvEorbtWcMgXvyX9bFAypVs=",
-    "x86_64-darwin": "sha256-6jVU7/uVId0VD24MVQ8s8Ill5b6PsKdlBgHg+oceKRg="
+    "x86_64-linux": "sha256-ZmAIcG3wPgssKejLe/EMJOjPuMHCyRiiItRvSqIjaME=",
+    "aarch64-linux": "sha256-lbAHoVI/CvgdrfKZ/9dKZ/O7DxJvuWEOrDgcCuFGPBk=",
+    "aarch64-darwin": "sha256-Nrs4ijvzQ3J8AYigJSlsr66feUvLZ5iiYCfBdaZNJEc=",
+    "x86_64-darwin": "sha256-ltCaJSO7kZWuMOU49269xvboNVX35OJDFj0gXCDf62Y="
  }
 }
@@ -153,6 +153,7 @@
    "@tanstack/solid-virtual@3.13.28": "patches/@tanstack%2Fsolid-virtual@3.13.28.patch",
    "@pierre/trees@1.0.0-beta.4": "patches/@pierre%2Ftrees@1.0.0-beta.4.patch",
    "@modelcontextprotocol/sdk@1.29.0": "patches/@modelcontextprotocol%2Fsdk@1.29.0.patch",
-    "@tanstack/virtual-core@3.17.0": "patches/@tanstack%2Fvirtual-core@3.17.0.patch"
+    "@tanstack/virtual-core@3.17.0": "patches/@tanstack%2Fvirtual-core@3.17.0.patch",
+    "effect@4.0.0-beta.83": "patches/effect@4.0.0-beta.83.patch"
  }
 }
@@ -0,0 +1,61 @@
+# Timeline Layout Continuity
+
+Run from `packages/app`:
+
+```sh
+bun run test:stability
+```
+
+The suite runs a production build in one Chromium worker. Selected scenarios use deterministic 4x CPU stress after application readiness. This is a stress profile, not emulation of a specific device.
+
+## What It Proves
+
+The continuity probe samples DOM-derived layout and visibility state across browser render opportunities. Tests declare explicit contracts such as:
+
+- Preserve a visible semantic anchor while the user is away from the bottom.
+- Preserve end anchoring while active content grows or new content appears.
+- Keep adjacent visible rows ordered without material overlap.
+- Keep user-selected disclosure state through updates and virtualization.
+- Avoid a sampled blank interval while one visible surface replaces another.
+- Preserve logical row and control identity where local state or focus depends on it.
+- Keep keyboard, wheel, and nested-scroll ownership consistent during remeasurement.
+
+The suite exercises real browser reducer, projection, component, virtualizer, layout, focus, and interaction code. The backend and event producer are controlled fixtures.
+
+## What It Does Not Prove
+
+The pass/fail oracle does not inspect every compositor-presented pixel. A sample taken after `requestAnimationFrame` is a DOM/layout observation, not proof that every sampled state was displayed or that every displayed frame was sampled.
+
+The suite does not provide complete coverage for:
+
+- Compositor-only or raster-only glitches.
+- Color, contrast, canvas, WebGL, masks, irregular clips, or arbitrary occlusion.
+- Physical display refresh rates, native OS scaling, or a named low-end device.
+- TCP packetization, proxy buffering, or the complete real server/provider pipeline.
+
+Playwright video, trace, screenshots, and observation JSON are diagnostic evidence. They are not pixel baselines and do not participate in normal pass/fail decisions.
+
+For optional before/violation/after screenshots, set `OPENCODE_STABILITY_CAPTURE=1`. Capture is opt-in because compositor readback can perturb timing.
+
+## Test Layers
+
+- **Projection:** admitted rows, grouping, labels, and final visible states.
+- **Local state:** disclosure state, identity, duplicate delivery, and virtualization restoration.
+- **Interaction:** wheel, keyboard, nested scrolling, actionability, and focus behavior.
+- **Layout continuity:** anchoring, adjacency, responsive reflow, and visible surface handoffs.
+- **Reducer hardening:** validly shaped but intentionally reordered, duplicated, removed, or replaced events.
+- **Oracle contract:** pure analyzer and browser sampler calibration tests.
+
+Production-lifecycle fixtures should model states emitted by the current producer. Impossible or reordered sequences belong in reducer-hardening tests and must not be described as normal provider behavior.
+
+## Diagnostics
+
+Failures retain:
+
+- `video.webm`
+- `trace.zip`
+- failure screenshot
+- sampled DOM/layout trace JSON
+- event markers and summarized violations
+
+The analyzer records both unclipped layout bounds and ancestor-clipped visible intersections. Scrollbar and raw `scrollTop` changes alone do not fail continuity checks; user-visible semantic anchor movement does.
@@ -0,0 +1,250 @@
+import { expect, test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  shell,
+  textPart,
+  toolPart,
+  userMessage,
+  waitForVisualSettle,
+  type TimelineMessage,
+} from "./fixture"
+
+test.describe("timeline adverse visual stability", () => {
+  test("does not pull a scrolled-away user while an active shell grows", async ({ page }, testInfo) => {
+    const activeShellID = "prt_adverse_01_shell"
+    const messages = [
+      ...history(24),
+      userMessage(),
+      assistantMessage([shell(activeShellID, "running")], { completed: false }),
+    ]
+    const timeline = await setupTimeline(page, {
+      messages,
+      settings: { shellToolPartsExpanded: true },
+      cpuRate: 4,
+      eventRetry: 30,
+    })
+    const scroller = page.locator(".scroll-view__viewport", {
+      has: page.locator('[data-timeline-row="AssistantPart"]'),
+    })
+    await scroller.evaluate((element) => {
+      element.dispatchEvent(new WheelEvent("wheel", { bubbles: true, cancelable: true, deltaY: -450 }))
+      element.scrollTop = Math.max(0, element.scrollHeight - element.clientHeight - 450)
+    })
+    await page.waitForTimeout(150)
+    await expect
+      .poll(() => scroller.evaluate((element) => element.scrollHeight - element.clientHeight - element.scrollTop))
+      .toBeGreaterThan(100)
+    const anchor = await scroller.evaluate((element) => {
+      const view = element.getBoundingClientRect()
+      return [...element.querySelectorAll<HTMLElement>("[data-timeline-key]")].find((row) => {
+        const rect = row.getBoundingClientRect()
+        return rect.top >= view.top + 40 && rect.bottom <= view.bottom - 40
+      })?.dataset.timelineKey
+    })
+    expect(anchor).toBeTruthy()
+    await waitForVisualSettle(page, [`[data-timeline-key="${anchor}"]`])
+
+    const regions = defineVisualRegions({
+      anchor: { selector: `[data-timeline-key="${anchor}"]` },
+    })
+    await startVisualProbe(page, regions)
+    await timeline.send(partUpdated(shell(activeShellID, "running", lines(1))), 180)
+    await timeline.send(partUpdated(shell(activeShellID, "running", lines(10))), 90)
+    await timeline.send(partUpdated(shell(activeShellID, "running", lines(50))), 350)
+    await timeline.send(partUpdated(shell(activeShellID, "completed", lines(50))), 500)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(
+      testInfo,
+      "scrolled-away-shell",
+      trace,
+      visualPlan(regions, [
+        { type: "required", regions: ["anchor"] },
+        { type: "unique", regions: ["anchor"] },
+        { type: "stable", regions: ["anchor"] },
+        { type: "fixed", regions: ["anchor"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxPositionReversals: 0 },
+        { type: "label-stability", regions: "all" },
+      ]),
+    )
+  })
+
+  test("preserves an explicit shell state across virtualization", async ({ page }) => {
+    const targetID = "prt_virtual_shell"
+    const messages = [
+      userMessage(undefined, { id: "msg_0000_virtual_user", created: 1700000000000 }),
+      assistantMessage([shell(targetID, "completed", lines(20))], {
+        id: "msg_0001_virtual_assistant",
+        parentID: "msg_0000_virtual_user",
+        created: 1700000001000,
+      }),
+      ...history(35, 10),
+    ]
+    await setupTimeline(page, { messages, settings: { shellToolPartsExpanded: false } })
+    const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+    await scroller.evaluate((element) => {
+      element.dispatchEvent(new WheelEvent("wheel", { bubbles: true, cancelable: true, deltaY: -1_000 }))
+      element.scrollTop = 0
+    })
+    await page.waitForTimeout(300)
+    const trigger = page.locator(`[data-timeline-part-id="${targetID}"] [data-slot="collapsible-trigger"]`)
+    await expect(trigger).toBeVisible()
+    await trigger.click()
+    await expect(trigger).toHaveAttribute("aria-expanded", "true")
+
+    await scroller.evaluate((element) => (element.scrollTop = element.scrollHeight))
+    await expect(page.locator(`[data-timeline-part-id="${targetID}"]`)).toHaveCount(0)
+    await scroller.evaluate((element) => (element.scrollTop = 0))
+    await expect(trigger).toBeVisible()
+    await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  })
+
+  test("keeps narrow viewport rows ordered during long shell growth", async ({ page }, testInfo) => {
+    const shellID = "prt_narrow_01_shell"
+    const followingID = "prt_narrow_02_following"
+    const timeline = await setupTimeline(page, {
+      messages: [
+        userMessage(),
+        assistantMessage(
+          [shell(shellID, "running"), textPart(followingID, "A narrow following row that wraps across lines.")],
+          {
+            completed: false,
+          },
+        ),
+      ],
+      settings: { shellToolPartsExpanded: true },
+      viewport: { width: 430, height: 800 },
+      cpuRate: 4,
+    })
+    await waitForVisualSettle(page, [
+      `[data-timeline-part-id="${shellID}"]`,
+      `[data-timeline-part-id="${followingID}"]`,
+    ])
+    const regions = defineVisualRegions({
+      shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+      following: {
+        selector: `[data-timeline-part-id="${followingID}"]`,
+        closest: '[data-timeline-row="AssistantPart"]',
+      },
+    })
+    await startVisualProbe(page, regions)
+    await timeline.send(partUpdated(shell(shellID, "running", wideLines(10))), 100)
+    await timeline.send(partUpdated(shell(shellID, "running", wideLines(50))), 300)
+    await timeline.send(partUpdated(shell(shellID, "completed", wideLines(50))), 500)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(
+      testInfo,
+      "narrow-shell",
+      trace,
+      visualPlan(
+        regions,
+        [
+          { type: "required", regions: ["shell", "following"] },
+          { type: "unique", regions: ["shell", "following"] },
+          { type: "stable", regions: ["shell", "following"] },
+          { type: "opacity", regions: "all" },
+          { type: "continuity", regions: "all" },
+          { type: "motion", regions: "all", maxPositionReversals: 0 },
+          { type: "label-stability", regions: "all" },
+          { type: "preserve-bottom-anchor" },
+          { type: "flow", regions: ["shell", "following"] },
+        ],
+        { perMarker: true },
+      ),
+    )
+  })
+
+  test("keeps visible rows ordered while resizing desktop to narrow and back", async ({ page }, testInfo) => {
+    const shellID = "prt_resize_01_shell"
+    const contextIDs = ["prt_resize_02_read", "prt_resize_03_glob"]
+    const followingID = "prt_resize_04_following"
+    await setupTimeline(page, {
+      messages: [
+        userMessage(),
+        assistantMessage([
+          shell(shellID, "completed", wideLines(15)),
+          toolPart(contextIDs[0]!, "read", "completed", { filePath: "src/a.ts" }),
+          toolPart(contextIDs[1]!, "glob", "completed", { path: ".", pattern: "**/*.ts" }),
+          textPart(followingID, "Following responsive timeline content that wraps on narrow screens."),
+        ]),
+      ],
+      settings: { shellToolPartsExpanded: true },
+      cpuRate: 4,
+      seedHistory: true,
+    })
+    const group = `[data-timeline-part-ids="${contextIDs.join(",")}"]`
+    const regions = defineVisualRegions({
+      shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+      context: { selector: group, closest: '[data-timeline-row="AssistantPart"]' },
+      following: {
+        selector: `[data-timeline-part-id="${followingID}"]`,
+        closest: '[data-timeline-row="AssistantPart"]',
+      },
+    })
+    await startVisualProbe(page, regions)
+    await page.setViewportSize({ width: 430, height: 800 })
+    await page.waitForTimeout(500)
+    await page.setViewportSize({ width: 900, height: 800 })
+    await page.waitForTimeout(500)
+    await page.setViewportSize({ width: 1400, height: 900 })
+    await page.waitForTimeout(500)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(
+      testInfo,
+      "responsive-resize",
+      trace,
+      visualPlan(regions, [
+        { type: "required", regions: ["shell", "context", "following"] },
+        { type: "unique", regions: ["shell", "context", "following"] },
+        { type: "stable", regions: ["shell", "context", "following"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxPositionReversals: 4, maxReversals: 4 },
+        { type: "label-stability", regions: "all" },
+        { type: "flow", regions: ["shell", "context", "following"] },
+      ]),
+    )
+  })
+})
+
+function history(count: number, offset = 0): TimelineMessage[] {
+  return Array.from({ length: count }, (_, index) => {
+    const value = index + offset
+    const prefix = `msg_0${String(value).padStart(3, "0")}_history`
+    const userID = `${prefix}_a_user`
+    return [
+      userMessage(undefined, { id: userID, created: 1699990000000 + value * 10_000 }),
+      assistantMessage(
+        [
+          textPart(
+            `prt_history_${String(value).padStart(3, "0")}`,
+            `Historical response ${value}. ${"Stable history content. ".repeat(8)}`,
+          ),
+        ],
+        {
+          id: `${prefix}_b_assistant`,
+          parentID: userID,
+          created: 1699990001000 + value * 10_000,
+        },
+      ),
+    ]
+  }).flat()
+}
+
+function lines(count: number) {
+  return Array.from({ length: count }, (_, index) => `line ${index + 1}`).join("\n")
+}
+
+function wideLines(count: number) {
+  return Array.from({ length: count }, (_, index) => `line ${index + 1} ${"wide-output-".repeat(20)}`).join("\n")
+}
@@ -0,0 +1,192 @@
+import { expect, test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantID,
+  assistantMessage,
+  event,
+  partUpdated,
+  setupTimeline,
+  textPart,
+  toolPart,
+  userMessage,
+  waitForVisualSettle,
+} from "./fixture"
+
+const inputs = {
+  read: { filePath: "src/a.ts", offset: 0, limit: 120 },
+  glob: { path: ".", pattern: "**/*.ts" },
+  grep: { path: ".", pattern: "stable", include: "*.ts" },
+  list: { path: "src" },
+}
+
+test("appends context operations while the group is expanded", async ({ page }, testInfo) => {
+  const firstID = "prt_append_01_read"
+  const followingID = "prt_append_99_following"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([toolPart(firstID, "read", "running", inputs.read), textPart(followingID, "Following append")], {
+        completed: false,
+      }),
+    ],
+    cpuRate: 4,
+  })
+  const initialGroup = `[data-timeline-part-ids="${firstID}"]`
+  await page.locator(`${initialGroup} [data-slot="collapsible-trigger"]`).click()
+  await waitForVisualSettle(page, [initialGroup, `[data-timeline-part-id="${followingID}"]`])
+  const regions = defineVisualRegions({
+    context: {
+      selector: '[data-timeline-part-ids^="prt_append_01_read"]',
+      closest: '[data-timeline-row="AssistantPart"]',
+    },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(partUpdated(toolPart("prt_append_02_glob", "glob", "running", inputs.glob)), 180)
+  await timeline.send(partUpdated(toolPart("prt_append_03_grep", "grep", "completed", inputs.grep)), 240)
+  await timeline.send(partUpdated(toolPart("prt_append_04_list", "list", "completed", inputs.list)), 500)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "context-append",
+    trace,
+    visualPlan(
+      regions,
+      [
+        { type: "required", regions: ["context", "following"] },
+        { type: "unique", regions: ["context", "following"] },
+        { type: "stable", regions: ["context", "following"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: ["following"], maxPositionReversals: 0 },
+        { type: "label-stability", regions: "all" },
+        { type: "preserve-bottom-anchor" },
+        { type: "flow", regions: ["context", "following"] },
+      ],
+      { perMarker: true },
+    ),
+  )
+  await expect(
+    page.locator(
+      '[data-timeline-part-ids="prt_append_01_read,prt_append_02_glob,prt_append_03_grep,prt_append_04_list"]',
+    ),
+  ).toBeVisible()
+  await expect(
+    page.locator('[data-timeline-part-ids^="prt_append_01_read"] [data-slot="collapsible-trigger"]'),
+  ).toHaveAttribute("aria-expanded", "true")
+})
+
+test("splits and merges context groups when a middle text part changes", async ({ page }, testInfo) => {
+  const textID = "prt_split_02_text"
+  const followingID = "prt_split_99_following"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([
+        toolPart("prt_split_01_read", "read", "completed", inputs.read),
+        textPart(textID, "Boundary"),
+        toolPart("prt_split_03_glob", "glob", "completed", inputs.glob),
+        textPart(followingID, "Following split groups"),
+      ]),
+    ],
+    cpuRate: 4,
+  })
+  const regions = defineVisualRegions({
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(
+    event("message.part.removed", { sessionID: "ses_timeline_stability", messageID: assistantID, partID: textID }),
+    500,
+  )
+  await expect(page.locator('[data-timeline-part-ids="prt_split_01_read,prt_split_03_glob"]')).toBeVisible()
+  await timeline.send(partUpdated(textPart(textID, "Boundary restored")), 500)
+  await expect(page.locator('[data-timeline-part-ids="prt_split_01_read"]')).toBeVisible()
+  await expect(page.locator('[data-timeline-part-ids="prt_split_03_glob"]')).toBeVisible()
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "context-split-merge",
+    trace,
+    visualPlan(
+      regions,
+      [
+        { type: "required", regions: ["following"] },
+        { type: "unique", regions: ["following"] },
+        { type: "stable", regions: ["following"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxPositionReversals: 1 },
+        { type: "label-stability", regions: "all" },
+      ],
+      { perMarker: true },
+    ),
+  )
+})
+
+test("removing the first context member replaces the group once without overlapping following content", async ({
+  page,
+}, testInfo) => {
+  const ids = ["prt_key_01_read", "prt_key_02_glob", "prt_key_03_grep"]
+  const followingID = "prt_key_99_following"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([
+        toolPart(ids[0]!, "read", "completed", inputs.read),
+        toolPart(ids[1]!, "glob", "completed", inputs.glob),
+        toolPart(ids[2]!, "grep", "completed", inputs.grep),
+        textPart(followingID, "Following replaced group"),
+      ]),
+    ],
+    cpuRate: 4,
+  })
+  const original = page.locator(`[data-timeline-part-ids="${ids.join(",")}"]`)
+  const originalRowKey = await original.evaluate((element) =>
+    element.closest("[data-timeline-key]")?.getAttribute("data-timeline-key"),
+  )
+  await original.locator('[data-slot="collapsible-trigger"]').click()
+  await expect(original.locator('[data-slot="collapsible-trigger"]')).toHaveAttribute("aria-expanded", "true")
+  const regions = defineVisualRegions({
+    context: {
+      selector: '[data-timeline-part-ids*="prt_key_02_glob"]',
+      closest: '[data-timeline-row="AssistantPart"]',
+    },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(
+    event("message.part.removed", { sessionID: "ses_timeline_stability", messageID: assistantID, partID: ids[0] }),
+    500,
+  )
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "context-first-remove",
+    trace,
+    visualPlan(regions, [
+      { type: "required", regions: ["context", "following"] },
+      { type: "unique", regions: ["context", "following"] },
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all", maxPositionReversals: 0 },
+      { type: "label-stability", regions: "all" },
+      { type: "flow", regions: ["context", "following"] },
+    ]),
+  )
+  await expect(page.locator(`[data-timeline-part-ids="${ids.slice(1).join(",")}"]`)).toBeVisible()
+  expect(
+    await page
+      .locator(`[data-timeline-part-ids="${ids.slice(1).join(",")}"]`)
+      .evaluate((element) => element.closest("[data-timeline-key]")?.getAttribute("data-timeline-key")),
+  ).toBe(originalRowKey)
+  await expect(
+    page.locator(`[data-timeline-part-ids="${ids.slice(1).join(",")}"] [data-slot="collapsible-trigger"]`),
+  ).toHaveAttribute("aria-expanded", "true")
+})
@@ -0,0 +1,113 @@
+import { test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  shell,
+  textPart,
+  userMessage,
+  waitForVisualSettle,
+} from "./fixture"
+
+// Fractional scaling exercises different browser rounding than the baseline.
+for (const deviceScaleFactor of [1, 1.25]) {
+  test(`keeps shell growth ordered at device scale ${deviceScaleFactor}`, async ({ page }, testInfo) => {
+    const shellID = `prt_dpr_${String(deviceScaleFactor).replace(".", "_")}_01_shell`
+    const followingID = `prt_dpr_${String(deviceScaleFactor).replace(".", "_")}_02_following`
+    const timeline = await setupTimeline(page, {
+      messages: [
+        userMessage(),
+        assistantMessage([shell(shellID, "running"), textPart(followingID, "Following scaled shell")], {
+          completed: false,
+        }),
+      ],
+      settings: { shellToolPartsExpanded: true },
+      cpuRate: 4,
+      deviceScaleFactor,
+      seedHistory: true,
+    })
+    await waitForVisualSettle(page, [
+      `[data-timeline-part-id="${shellID}"]`,
+      `[data-timeline-part-id="${followingID}"]`,
+    ])
+    const regions = defineVisualRegions({
+      shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+      following: {
+        selector: `[data-timeline-part-id="${followingID}"]`,
+        closest: '[data-timeline-row="AssistantPart"]',
+      },
+    })
+    await startVisualProbe(page, regions)
+    await timeline.send(partUpdated(shell(shellID, "running", lines(20))), 180)
+    await timeline.send(partUpdated(shell(shellID, "completed", lines(20))), 500)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(testInfo, `dpr-${deviceScaleFactor}`, trace, shellPlan(regions))
+  })
+}
+
+for (const reducedMotion of [true]) {
+  test(`keeps shell and status transitions ordered with reduced motion ${reducedMotion}`, async ({
+    page,
+  }, testInfo) => {
+    const shellID = `prt_motion_${reducedMotion}_01_shell`
+    const followingID = `prt_motion_${reducedMotion}_02_following`
+    const timeline = await setupTimeline(page, {
+      messages: [
+        userMessage(),
+        assistantMessage([shell(shellID, "running"), textPart(followingID, "Following motion profile")], {
+          completed: false,
+        }),
+      ],
+      settings: { shellToolPartsExpanded: true },
+      reducedMotion,
+      cpuRate: 4,
+      seedHistory: true,
+    })
+    await waitForVisualSettle(page, [
+      `[data-timeline-part-id="${shellID}"]`,
+      `[data-timeline-part-id="${followingID}"]`,
+    ])
+    const regions = defineVisualRegions({
+      shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+      following: {
+        selector: `[data-timeline-part-id="${followingID}"]`,
+        closest: '[data-timeline-row="AssistantPart"]',
+      },
+    })
+    await startVisualProbe(page, regions)
+    await timeline.send(partUpdated(shell(shellID, "completed", lines(10))), 500)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(testInfo, `reduced-motion-${reducedMotion}`, trace, shellPlan(regions))
+  })
+}
+
+function lines(count: number) {
+  return Array.from({ length: count }, (_, index) => `line ${index + 1}`).join("\n")
+}
+
+function shellPlan<Regions extends ReturnType<typeof defineVisualRegions>>(
+  regions: Regions & Record<"shell" | "following", { selector: string }>,
+) {
+  return visualPlan(
+    regions,
+    [
+      { type: "required", regions: ["shell", "following"] },
+      { type: "unique", regions: ["shell", "following"] },
+      { type: "stable", regions: ["shell", "following"] },
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all", maxPositionReversals: 0 },
+      { type: "label-stability", regions: "all" },
+      { type: "preserve-bottom-anchor" },
+      { type: "flow", regions: ["shell", "following"] },
+    ],
+    { perMarker: true },
+  )
+}
@@ -0,0 +1,121 @@
+import { test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  textPart,
+  toolPart,
+  userMessage,
+  waitForVisualSettle,
+} from "./fixture"
+
+const profiles = [
+  { name: "edit", tool: "edit", input: { filePath: "src/edit.ts" } },
+  {
+    name: "multi patch",
+    tool: "apply_patch",
+    input: { files: ["src/a.ts", "src/b.ts", "src/old.ts", "src/moved.ts"] },
+  },
+] as const
+
+for (const profile of profiles) {
+  test(`stabilizes ${profile.name} pending to completed`, async ({ page }, testInfo) => {
+    const partID = `prt_file_matrix_${profiles.indexOf(profile)}`
+    const followingID = `prt_file_matrix_following_${profiles.indexOf(profile)}`
+    const timeline = await setupTimeline(page, {
+      messages: [
+        userMessage(),
+        assistantMessage(
+          [
+            toolPart(partID, profile.tool, "pending", profile.input),
+            textPart(followingID, `Following ${profile.name}`),
+          ],
+          { completed: false },
+        ),
+      ],
+      settings: { editToolPartsExpanded: true },
+      cpuRate: 4,
+    })
+    await waitForVisualSettle(page, [`[data-timeline-part-id="${partID}"]`, `[data-timeline-part-id="${followingID}"]`])
+    const regions = defineVisualRegions({
+      tool: { selector: `[data-timeline-part-id="${partID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+      following: {
+        selector: `[data-timeline-part-id="${followingID}"]`,
+        closest: '[data-timeline-row="AssistantPart"]',
+      },
+    })
+    await startVisualProbe(page, regions)
+    await timeline.send(partUpdated(toolPart(partID, profile.tool, "running", profile.input)), 180)
+    await timeline.send(partUpdated(completedPart(partID, profile)), 900)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(
+      testInfo,
+      `file-${profile.name}`,
+      trace,
+      visualPlan(
+        regions,
+        [
+          { type: "required", regions: ["tool", "following"] },
+          { type: "unique", regions: ["tool", "following"] },
+          { type: "stable", regions: ["tool", "following"] },
+          { type: "opacity", regions: "all" },
+          { type: "continuity", regions: "all" },
+          { type: "motion", regions: "all", maxPositionReversals: 0, maxReversals: 1 },
+          { type: "label-stability", regions: "all" },
+          { type: "preserve-bottom-anchor" },
+          { type: "flow", regions: ["tool", "following"] },
+        ],
+        { perMarker: true },
+      ),
+    )
+  })
+}
+
+function completedPart(partID: string, profile: (typeof profiles)[number]) {
+  if (profile.tool === "edit") {
+    return toolPart(partID, profile.tool, "completed", profile.input, {
+      metadata: {
+        filediff: {
+          file: "src/edit.ts",
+          additions: 50,
+          deletions: 50,
+          before: source(50, false),
+          after: source(50, true),
+        },
+      },
+    })
+  }
+  const files = [
+    patchFile("src/a.ts", "update"),
+    patchFile("src/b.ts", "add"),
+    patchFile("src/old.ts", "delete"),
+    { ...patchFile("src/moved.ts", "move"), move: "src/new-place.ts" },
+  ]
+  return toolPart(partID, profile.tool, "completed", profile.input, { metadata: { files } })
+}
+
+function patchFile(filePath: string, type: "add" | "update" | "delete" | "move") {
+  return {
+    filePath,
+    relativePath: filePath,
+    type,
+    additions: type === "delete" ? 0 : 20,
+    deletions: type === "add" ? 0 : 20,
+    before: type === "add" ? undefined : source(20, false),
+    after: type === "delete" ? undefined : source(20, true),
+  }
+}
+
+function source(count: number, changed: boolean) {
+  return Array.from(
+    { length: count },
+    (_, index) => `export const value${index} = ${changed ? index + 1 : index}\n`,
+  ).join("")
+}
@@ -0,0 +1,113 @@
+import { expect, test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  textPart,
+  toolPart,
+  userMessage,
+  waitForVisualSettle,
+} from "./fixture"
+
+test("adds patch files incrementally without resetting outer expansion", async ({ page }, testInfo) => {
+  const patchID = "prt_incremental_01_patch"
+  const followingID = "prt_incremental_02_following"
+  const first = patchFile("src/a.ts", "update")
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage(
+        [
+          toolPart(patchID, "apply_patch", "running", { files: [first.filePath] }, { metadata: { files: [first] } }),
+          textPart(followingID, "Following incremental patch"),
+        ],
+        { completed: false },
+      ),
+    ],
+    settings: { editToolPartsExpanded: true },
+    cpuRate: 4,
+    seedHistory: true,
+  })
+  const trigger = page.locator(`[data-timeline-part-id="${patchID}"] [data-slot="collapsible-trigger"]`).first()
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  await waitForVisualSettle(page, [`[data-timeline-part-id="${patchID}"]`, `[data-timeline-part-id="${followingID}"]`])
+  const regions = defineVisualRegions({
+    patch: { selector: `[data-timeline-part-id="${patchID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  const second = patchFile("src/b.ts", "add")
+  const third = patchFile("src/old.ts", "delete")
+  await timeline.send(
+    partUpdated(
+      toolPart(
+        patchID,
+        "apply_patch",
+        "running",
+        { files: [first.filePath, second.filePath] },
+        { metadata: { files: [first, second] } },
+      ),
+    ),
+    240,
+  )
+  await timeline.send(
+    partUpdated(
+      toolPart(
+        patchID,
+        "apply_patch",
+        "completed",
+        { files: [first.filePath, second.filePath, third.filePath] },
+        { metadata: { files: [first, second, third] } },
+      ),
+    ),
+    800,
+  )
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "incremental-patch",
+    trace,
+    visualPlan(
+      regions,
+      [
+        { type: "required", regions: ["patch", "following"] },
+        { type: "unique", regions: ["patch", "following"] },
+        { type: "stable", regions: ["patch", "following"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: ["following"], maxPositionReversals: 0 },
+        { type: "label-stability", regions: "all" },
+        { type: "preserve-bottom-anchor" },
+        { type: "flow", regions: ["patch", "following"] },
+      ],
+      { perMarker: true },
+    ),
+  )
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  await expect(page.locator('[data-scope="apply-patch"] [data-type="delete"]')).toBeVisible()
+})
+
+function patchFile(filePath: string, type: "add" | "update" | "delete") {
+  return {
+    filePath,
+    relativePath: filePath,
+    type,
+    additions: type === "delete" ? 0 : 4,
+    deletions: type === "add" ? 0 : 3,
+    before: type === "add" ? undefined : source(false),
+    after: type === "delete" ? undefined : source(true),
+  }
+}
+
+function source(changed: boolean) {
+  return Array.from({ length: 12 }, (_, index) => `export const value${index} = ${changed ? index + 1 : index}\n`).join(
+    "",
+  )
+}
@@ -0,0 +1,68 @@
+import { describe, expect, test } from "bun:test"
+import {
+  assistantMessage,
+  event,
+  toolPart,
+  userMessage,
+  validateTimelineEvent,
+  validateTimelineMessages,
+  type PartSeed,
+} from "./fixture"
+
+describe("timeline fixture validation", () => {
+  test("accepts a valid timeline", () => {
+    expect(validateTimelineMessages([userMessage(), assistantMessage()])).toHaveLength(2)
+  })
+
+  test("rejects malformed SDK values at runtime", () => {
+    expect(() =>
+      assistantMessage([], {
+        error: { name: "APIError", data: { message: "failed" } } as never,
+      }),
+    ).toThrow()
+    expect(() =>
+      validateTimelineEvent({
+        directory: "C:/OpenCode/TimelineStability",
+        payload: {
+          id: "evt_invalid_status",
+          type: "session.status",
+          properties: { sessionID: "ses_timeline_stability", status: { type: "retry", attempt: 1 } },
+        },
+      }),
+    ).toThrow()
+  })
+
+  test("rejects duplicate IDs and orphan assistants", () => {
+    expect(() => validateTimelineMessages([userMessage(), userMessage()])).toThrow(/duplicate message ID/)
+    expect(() =>
+      validateTimelineMessages([userMessage(), assistantMessage([], { parentID: "msg_missing_parent" })]),
+    ).toThrow(/parent user/)
+  })
+
+  test("assigns deterministic event IDs", () => {
+    const first = event("session.status", { sessionID: "ses_timeline_stability", status: { type: "busy" } })
+    const second = event("session.status", { sessionID: "ses_timeline_stability", status: { type: "idle" } })
+    expect(first.payload.id).toMatch(/^evt_timeline_\d{4}$/)
+    expect(Number(second.payload.id.slice(-4))).toBe(Number(first.payload.id.slice(-4)) + 1)
+  })
+})
+
+if (false) {
+  const userSeed = { id: "prt_type_user", type: "text", text: "typed" } satisfies PartSeed<"user">
+  userMessage([userSeed])
+
+  // @ts-expect-error Tool completion fields are not valid while pending.
+  toolPart("prt_invalid_pending", "bash", "pending", {}, { output: "impossible" })
+  // @ts-expect-error Tool completion fields are not valid while running.
+  toolPart("prt_invalid_running", "bash", "running", {}, { output: "impossible" })
+  // @ts-expect-error Tool error fields are not valid after completion.
+  toolPart("prt_invalid_completed", "bash", "completed", {}, { error: "impossible" })
+
+  assistantMessage([
+    // @ts-expect-error Agent references belong to user messages, not assistant messages.
+    { id: "prt_invalid_owner", type: "agent", name: "explore", source: { value: "@explore", start: 0, end: 8 } },
+  ])
+
+  // @ts-expect-error Retry status events require message and next.
+  event("session.status", { sessionID: "ses_timeline_stability", status: { type: "retry", attempt: 1 } })
+}
@@ -0,0 +1,561 @@
+import { base64Encode } from "@opencode-ai/core/util/encode"
+import { Event } from "@opencode-ai/schema/event"
+import { SessionStatusEvent } from "@opencode-ai/schema/session-status-event"
+import { SessionV1 } from "@opencode-ai/schema/session-v1"
+import type {
+  AssistantMessage,
+  GlobalEvent,
+  Message,
+  Part,
+  Session,
+  SessionStatus,
+  ToolPart,
+  ToolState,
+  UserMessage,
+} from "@opencode-ai/sdk/v2/client"
+import { expect, type Page } from "@playwright/test"
+import { Schema } from "effect"
+import { mockOpenCodeServer } from "../../utils/mock-server"
+import { installSseTransport } from "../../utils/sse-transport"
+import { expectSessionTitle } from "../../utils/waits"
+
+export const directory = "C:/OpenCode/TimelineStability"
+export const projectID = "proj_timeline_stability"
+export const sessionID = "ses_timeline_stability"
+export const userID = "msg_1000_timeline_user"
+export const assistantID = "msg_1001_timeline_assistant"
+export const title = "Timeline visual stability"
+export const model = { providerID: "opencode", modelID: "claude-opus-4-6", variant: "max" }
+
+type TimelinePayload = Extract<
+  GlobalEvent["payload"],
+  {
+    type:
+      | "message.updated"
+      | "message.removed"
+      | "message.part.updated"
+      | "message.part.removed"
+      | "message.part.delta"
+      | "session.status"
+  }
+>
+
+type DeepReadonly<Value> = Value extends readonly unknown[]
+  ? { readonly [Key in keyof Value]: DeepReadonly<Value[Key]> }
+  : Value extends object
+    ? { readonly [Key in keyof Value]: DeepReadonly<Value[Key]> }
+    : Value
+
+export type TimelineEvent = DeepReadonly<Omit<GlobalEvent, "payload"> & { payload: TimelinePayload }>
+export type EventPayload = TimelineEvent
+export type ToolStatus = ToolState["status"]
+export type TimelineMessage = { info: UserMessage; parts: Part[] } | { info: AssistantMessage; parts: Part[] }
+
+type UserPart = Extract<Part, { type: "text" | "file" | "agent" | "subtask" }>
+type AssistantPart = Exclude<Part, { type: "agent" | "subtask" }>
+type OwnedPart<Owner extends Message["role"]> = Owner extends "user" ? UserPart : AssistantPart
+export type PartSeed<Owner extends Message["role"]> =
+  OwnedPart<Owner> extends infer Candidate
+    ? Candidate extends Part
+      ? Omit<Candidate, "sessionID" | "messageID">
+      : never
+    : never
+
+type ToolOptions<State extends ToolStatus> = State extends "pending"
+  ? { output?: never; title?: never; metadata?: never; error?: never }
+  : State extends "running"
+    ? { title?: string; metadata?: Record<string, unknown>; output?: never; error?: never }
+    : State extends "error"
+      ? { error?: string; metadata?: Record<string, unknown>; output?: never; title?: never }
+      : { output?: string; title?: string; metadata?: Record<string, unknown>; error?: never }
+
+const decodeOptions = { errors: "all", onExcessProperty: "error" } as const
+const decodeMessage = Schema.decodeUnknownSync(SessionV1.WithParts)
+const decodePart = Schema.decodeUnknownSync(SessionV1.Part)
+const decodeStatus = Schema.decodeUnknownSync(SessionStatusEvent.Info)
+const timelineEventSchema = Schema.Union([
+  eventSchema("message.updated", SessionV1.Event.MessageUpdated.data),
+  eventSchema("message.removed", SessionV1.Event.MessageRemoved.data),
+  eventSchema("message.part.updated", SessionV1.Event.PartUpdated.data),
+  eventSchema("message.part.removed", SessionV1.Event.PartRemoved.data),
+  eventSchema("message.part.delta", SessionV1.Event.PartDelta.data),
+  eventSchema("session.status", SessionStatusEvent.Status.data),
+])
+const decodeEvent = Schema.decodeUnknownSync(timelineEventSchema)
+let eventSequence = 0
+
+export async function setupTimeline(
+  page: Page,
+  input: {
+    messages?: TimelineMessage[]
+    settings?: Record<string, boolean>
+    sessions?: Session[]
+    cpuRate?: number
+    viewport?: { width: number; height: number }
+    eventRetry?: number
+    reducedMotion?: boolean
+    locale?: string
+    deviceScaleFactor?: number
+    seedHistory?: boolean
+  } = {},
+) {
+  const sessions = input.sessions ?? [session()]
+  const messages = validateTimelineMessages([
+    ...(input.seedHistory ? historyMessages(18) : []),
+    ...(input.messages ?? [userMessage(), assistantMessage()]),
+  ])
+  const active = messages.findLast((message) => message.info.role === "assistant")
+  const initialStatus = decodeStatus(
+    active?.info.role === "assistant" && active.info.time.completed === undefined ? { type: "busy" } : { type: "idle" },
+    decodeOptions,
+  )
+  const transport = await installSseTransport<EventPayload>(page, {
+    server: `http://${process.env.PLAYWRIGHT_SERVER_HOST ?? "127.0.0.1"}:${process.env.PLAYWRIGHT_SERVER_PORT ?? "4096"}`,
+    retry: input.eventRetry ?? 20,
+  })
+  await mockOpenCodeServer(page, {
+    directory,
+    project: project(),
+    provider: provider(),
+    sessions,
+    sessionStatus: { [sessionID]: initialStatus },
+    pageMessages: () => ({
+      items: messages,
+    }),
+  })
+  await page.addInitScript((settings) => {
+    localStorage.setItem(
+      "settings.v3",
+      JSON.stringify({
+        general: {
+          editToolPartsExpanded: false,
+          shellToolPartsExpanded: false,
+          showReasoningSummaries: false,
+          showSessionProgressBar: true,
+          ...settings,
+        },
+      }),
+    )
+  }, input.settings ?? {})
+  if (input.locale) {
+    await page.addInitScript((locale) => {
+      localStorage.setItem("opencode.global.dat:language", JSON.stringify({ locale }))
+    }, input.locale)
+  }
+  if (input.reducedMotion) await page.emulateMedia({ reducedMotion: "reduce" })
+  await page.setViewportSize(input.viewport ?? { width: 1400, height: 900 })
+  if (input.deviceScaleFactor) {
+    const devtools = await page.context().newCDPSession(page)
+    const viewport = input.viewport ?? { width: 1400, height: 900 }
+    await devtools.send("Emulation.setDeviceMetricsOverride", {
+      width: viewport.width,
+      height: viewport.height,
+      deviceScaleFactor: input.deviceScaleFactor,
+      mobile: false,
+    })
+  }
+  await page.goto(`/${base64Encode(directory)}/session/${sessionID}`)
+  await transport.waitForConnection()
+  await expectSessionTitle(page, title)
+  if (input.cpuRate && input.cpuRate > 1) {
+    const devtools = await page.context().newCDPSession(page)
+    await devtools.send("Emulation.setCPUThrottlingRate", { rate: input.cpuRate })
+  }
+
+  return {
+    transport,
+    async send(event: TimelineEvent, delay = 0) {
+      const valid = validateTimelineEvent(event)
+      await transport.send(valid, { marker: describeEvent(valid) })
+      if (delay) await page.waitForTimeout(delay)
+    },
+    async sendAll(sequence: { event: TimelineEvent; delay: number }[]) {
+      for (const item of sequence) {
+        const valid = validateTimelineEvent(item.event)
+        await transport.send(valid, { marker: describeEvent(valid) })
+        await page.waitForTimeout(item.delay)
+      }
+    },
+    async settle(frames = 3) {
+      await page.evaluate(
+        (frames) =>
+          new Promise<void>((resolve) => {
+            let remaining = frames
+            const tick = () => {
+              remaining--
+              if (remaining <= 0) return resolve()
+              requestAnimationFrame(tick)
+            }
+            requestAnimationFrame(tick)
+          }),
+        frames,
+      )
+    },
+    async waitForPart(partID: string) {
+      await expect(page.locator(`[data-timeline-part-id="${partID}"]`).first()).toBeVisible()
+    },
+  }
+}
+
+function describeEvent(event: EventPayload) {
+  if (event.payload.type === "message.part.updated") {
+    const part = event.payload.properties.part
+    return [
+      event.payload.type,
+      part.id,
+      part.type === "tool" ? part.tool : part.type,
+      part.type === "tool" ? part.state.status : undefined,
+    ]
+      .filter(Boolean)
+      .join(":")
+  }
+  if (event.payload.type === "session.status") {
+    const status = event.payload.properties.status
+    return [event.payload.type, status.type, status.type === "retry" ? status.attempt : undefined]
+      .filter((value) => value !== undefined)
+      .join(":")
+  }
+  return event.payload.type
+}
+
+export function event<const Type extends TimelinePayload["type"]>(
+  type: Type,
+  properties: Extract<TimelinePayload, { type: Type }>["properties"],
+): TimelineEvent
+export function event(type: TimelinePayload["type"], properties: TimelinePayload["properties"]): TimelineEvent {
+  return validateTimelineEvent({
+    directory,
+    payload: { id: `evt_timeline_${String(++eventSequence).padStart(4, "0")}`, type, properties },
+  })
+}
+
+export function validateTimelineEvent(input: unknown): TimelineEvent {
+  return decodeEvent(input, decodeOptions)
+}
+
+export function validateTimelineMessages(input: readonly TimelineMessage[]): TimelineMessage[] {
+  input.forEach((message) => decodeMessage(message, decodeOptions))
+  const messages = [...input]
+  const messageIDs = new Set<string>()
+  const partIDs = new Set<string>()
+  const users = new Set(messages.filter((message) => message.info.role === "user").map((message) => message.info.id))
+
+  messages.forEach((message) => {
+    if (messageIDs.has(message.info.id))
+      throw new Error(`Timeline fixture has duplicate message ID: ${message.info.id}`)
+    messageIDs.add(message.info.id)
+    if (message.info.role === "assistant" && !users.has(message.info.parentID))
+      throw new Error(`Timeline assistant ${message.info.id} must reference a parent user in the fixture`)
+    message.parts.forEach((part) => {
+      if (part.sessionID !== message.info.sessionID || part.messageID !== message.info.id)
+        throw new Error(`Timeline part ${part.id} ownership does not match message ${message.info.id}`)
+      if (message.info.role === "user" && !["text", "file", "agent", "subtask"].includes(part.type))
+        throw new Error(`Timeline user message ${message.info.id} cannot own ${part.type} part ${part.id}`)
+      if (message.info.role === "assistant" && ["agent", "subtask"].includes(part.type))
+        throw new Error(`Timeline assistant message ${message.info.id} cannot own ${part.type} part ${part.id}`)
+      if (partIDs.has(part.id)) throw new Error(`Timeline fixture has duplicate part ID: ${part.id}`)
+      partIDs.add(part.id)
+    })
+  })
+  return messages
+}
+
+export async function waitForVisualSettle(page: Page, selectors: string[], stableFrames = 3) {
+  await page.waitForFunction(
+    ({ selectors, stableFrames }) => {
+      const elements = selectors.map((selector) => document.querySelector<HTMLElement>(selector))
+      if (elements.some((element) => !element)) return false
+      return new Promise<boolean>((resolve) => {
+        let stable = 0
+        let previous = ""
+        const sample = () => {
+          const signature = JSON.stringify(
+            elements.map((element) => {
+              const rect = element!.getBoundingClientRect()
+              return [Math.round(rect.top * 10), Math.round(rect.bottom * 10), Math.round(rect.height * 10)]
+            }),
+          )
+          stable = signature === previous ? stable + 1 : 0
+          previous = signature
+          const ordered = elements
+            .slice(1)
+            .every(
+              (element, index) =>
+                elements[index]!.getBoundingClientRect().bottom <= element!.getBoundingClientRect().top + 0.5,
+            )
+          if (stable >= stableFrames && ordered) return resolve(true)
+          requestAnimationFrame(sample)
+        }
+        requestAnimationFrame(sample)
+      })
+    },
+    { selectors, stableFrames },
+  )
+}
+
+export function historyMessages(count: number): TimelineMessage[] {
+  return Array.from({ length: count }, (_, index) => {
+    const value = String(index).padStart(4, "0")
+    const historyUserID = `msg_0${value}_history_a_user`
+    return [
+      userMessage(undefined, { id: historyUserID, created: 1690000000000 + index * 10_000 }),
+      assistantMessage(
+        [
+          {
+            id: `prt_0${value}_history_text`,
+            type: "text",
+            text: `Historical response ${index}. ${"Existing session content keeps the virtual timeline realistic. ".repeat(5)}`,
+          },
+        ],
+        {
+          id: `msg_0${value}_history_b_assistant`,
+          parentID: historyUserID,
+          created: 1690000001000 + index * 10_000,
+        },
+      ),
+    ]
+  }).flat()
+}
+
+export function partUpdated(part: Part | PartSeed<"assistant">) {
+  const owned = "messageID" in part ? part : { ...part, sessionID, messageID: assistantID }
+  decodePart(owned, decodeOptions)
+  return event("message.part.updated", {
+    sessionID,
+    part: owned,
+    time: 1700000002000,
+  })
+}
+
+export function partDelta(partID: string, delta: string, messageID = assistantID) {
+  return event("message.part.delta", { sessionID, messageID, partID, field: "text", delta })
+}
+
+export function messageUpdated(info: Message) {
+  return event("message.updated", { sessionID, info })
+}
+
+export function status(type: SessionStatus["type"], attempt = 1) {
+  return event("session.status", {
+    sessionID,
+    status: type === "retry" ? { type, attempt, message: "Rate limited", next: 1700000010000 } : { type },
+  })
+}
+
+export function userMessage(
+  parts?: PartSeed<"user">[],
+  input: { id?: string; summary?: UserMessage["summary"]; created?: number } = {},
+): Extract<TimelineMessage, { info: { role: "user" } }> {
+  const id = input.id ?? userID
+  const seeds = parts ?? [userText("Build the timeline stability matrix.", { id: `prt_${id}_text` })]
+  const message = {
+    info: {
+      id,
+      sessionID,
+      role: "user",
+      time: { created: input.created ?? 1700000000000 },
+      summary: input.summary ?? { diffs: [] },
+      agent: "build",
+      model,
+    },
+    parts: seeds.map((part) => ({
+      ...part,
+      sessionID,
+      messageID: id,
+    })),
+  } satisfies Extract<TimelineMessage, { info: { role: "user" } }>
+  decodeMessage(message, decodeOptions)
+  return message
+}
+
+export function assistantMessage(
+  parts: PartSeed<"assistant">[] = [],
+  input: {
+    id?: string
+    parentID?: string
+    completed?: boolean
+    error?: AssistantMessage["error"]
+    created?: number
+  } = {},
+): Extract<TimelineMessage, { info: { role: "assistant" } }> {
+  const id = input.id ?? assistantID
+  const message = {
+    info: {
+      id,
+      sessionID,
+      role: "assistant",
+      time: {
+        created: input.created ?? 1700000001000,
+        ...(input.completed === false ? {} : { completed: (input.created ?? 1700000001000) + 1_000 }),
+      },
+      parentID: input.parentID ?? userID,
+      modelID: model.modelID,
+      providerID: model.providerID,
+      mode: "build",
+      agent: "build",
+      path: { cwd: directory, root: directory },
+      cost: 0.01,
+      tokens: { input: 100, output: 200, reasoning: 0, cache: { read: 0, write: 0 } },
+      variant: "max",
+      ...(input.error ? { error: input.error } : {}),
+    },
+    parts: parts.map((part) => ({ ...part, sessionID, messageID: id })),
+  } satisfies Extract<TimelineMessage, { info: { role: "assistant" } }>
+  decodeMessage(message, decodeOptions)
+  return message
+}
+
+export function userText(
+  text: string,
+  input: Partial<Omit<Extract<PartSeed<"user">, { type: "text" }>, "type" | "text">> = {},
+): Extract<PartSeed<"user">, { type: "text" }> {
+  return { id: "prt_user_text", type: "text", text, ...input }
+}
+
+export function textPart(id: string, text: string): Extract<PartSeed<"assistant">, { type: "text" }> {
+  return { id, type: "text", text }
+}
+
+export function reasoningPart(id: string, text: string): Extract<PartSeed<"assistant">, { type: "reasoning" }> {
+  return { id, type: "reasoning", text, time: { start: 1700000001000 } }
+}
+
+export function toolPart(
+  id: string,
+  tool: string,
+  state: "pending",
+  input: Record<string, unknown>,
+  options?: ToolOptions<"pending">,
+): Omit<ToolPart, "sessionID" | "messageID">
+export function toolPart(
+  id: string,
+  tool: string,
+  state: "running",
+  input: Record<string, unknown>,
+  options?: ToolOptions<"running">,
+): Omit<ToolPart, "sessionID" | "messageID">
+export function toolPart(
+  id: string,
+  tool: string,
+  state: "completed",
+  input: Record<string, unknown>,
+  options?: ToolOptions<"completed">,
+): Omit<ToolPart, "sessionID" | "messageID">
+export function toolPart(
+  id: string,
+  tool: string,
+  state: "error",
+  input: Record<string, unknown>,
+  options?: ToolOptions<"error">,
+): Omit<ToolPart, "sessionID" | "messageID">
+export function toolPart(
+  id: string,
+  tool: string,
+  state: ToolStatus,
+  input: Record<string, unknown>,
+  options: ToolOptions<ToolStatus> = {},
+): Omit<ToolPart, "sessionID" | "messageID"> {
+  const base = { id, type: "tool" as const, callID: `call_${id}`, tool }
+  if (state === "pending") return { ...base, state: { status: state, input, raw: "" } }
+  if (state === "running")
+    return {
+      ...base,
+      state: {
+        status: state,
+        input,
+        title: options.title,
+        metadata: options.metadata ?? {},
+        time: { start: 1700000001000 },
+      },
+    }
+  if (state === "error")
+    return {
+      ...base,
+      state: {
+        status: state,
+        input,
+        error: options.error ?? "Tool failed",
+        metadata: options.metadata ?? {},
+        time: { start: 1700000001000, end: 1700000002000 },
+      },
+    }
+  return {
+    ...base,
+    state: {
+      status: state,
+      input,
+      output: options.output ?? "Completed",
+      title: options.title ?? tool,
+      metadata: options.metadata ?? {},
+      time: { start: 1700000001000, end: 1700000002000 },
+    },
+  }
+}
+
+export function shell(
+  id: string,
+  state: ToolStatus,
+  output = "",
+  command = `echo ${id}`,
+): Omit<ToolPart, "sessionID" | "messageID"> {
+  if (state === "pending") return toolPart(id, "bash", state, { command })
+  if (state === "running")
+    return toolPart(id, "bash", state, { command }, { title: command, metadata: { command, output } })
+  if (state === "error")
+    return toolPart(id, "bash", state, { command }, { error: output || undefined, metadata: { command, output } })
+  return toolPart(id, "bash", state, { command }, { title: command, output, metadata: { command, output } })
+}
+
+export function completedAssistantInfo(info: AssistantMessage): AssistantMessage {
+  return { ...info, time: { ...info.time, completed: 1700000003000 } }
+}
+
+export function project() {
+  return {
+    id: projectID,
+    worktree: directory,
+    vcs: "git",
+    name: "timeline-stability",
+    time: { created: 1700000000000, updated: 1700000000000 },
+    sandboxes: [],
+  }
+}
+
+export function session(input: Partial<Session> = {}): Session {
+  return {
+    id: sessionID,
+    slug: "timeline-stability",
+    projectID,
+    directory,
+    title,
+    version: "dev",
+    time: { created: 1700000000000, updated: 1700000000000 },
+    ...input,
+  }
+}
+
+function eventSchema<
+  const Type extends TimelinePayload["type"],
+  const Properties extends Schema.Codec<unknown, unknown>,
+>(type: Type, properties: Properties) {
+  return Schema.Struct({
+    directory: Schema.String,
+    project: Schema.optional(Schema.String),
+    workspace: Schema.optional(Schema.String),
+    payload: Schema.Struct({ id: Event.ID, type: Schema.Literal(type), properties }),
+  })
+}
+
+function provider() {
+  return {
+    all: [
+      {
+        id: "opencode",
+        name: "OpenCode",
+        models: { "claude-opus-4-6": { id: "claude-opus-4-6", name: "Claude Opus 4.6", limit: { context: 200_000 } } },
+      },
+    ],
+    connected: ["opencode"],
+    default: { providerID: "opencode", modelID: "claude-opus-4-6" },
+  }
+}
@@ -0,0 +1,242 @@
+import { expect, test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import { assistantMessage, setupTimeline, shell, textPart, toolPart, userMessage, waitForVisualSettle } from "./fixture"
+
+test("expands and collapses a long completed shell without overlap", async ({ page }, testInfo) => {
+  const shellID = "prt_interaction_01_shell"
+  const followingID = "prt_interaction_02_following"
+  await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([shell(shellID, "completed", lines(50)), textPart(followingID, "Following shell expansion")]),
+    ],
+    settings: { shellToolPartsExpanded: false },
+    cpuRate: 4,
+    seedHistory: true,
+  })
+  const trigger = page.locator(`[data-timeline-part-id="${shellID}"] [data-slot="collapsible-trigger"]`)
+  await waitForVisualSettle(page, [`[data-timeline-part-id="${shellID}"]`, `[data-timeline-part-id="${followingID}"]`])
+  const regions = defineVisualRegions({
+    shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  const plan = visualPlan(regions, [
+    { type: "required", regions: ["shell", "following"] },
+    { type: "unique", regions: ["shell", "following"] },
+    { type: "stable", regions: ["shell", "following"] },
+    { type: "opacity", regions: "all" },
+    { type: "continuity", regions: "all" },
+    { type: "motion", regions: "all", maxPositionReversals: 0 },
+    { type: "label-stability", regions: "all" },
+    { type: "preserve-bottom-anchor" },
+    { type: "flow", regions: ["shell", "following"] },
+  ])
+  await startVisualProbe(page, regions)
+  await trigger.click()
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  await page.waitForTimeout(500)
+  const expanded = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(testInfo, "shell-expand", expanded, plan)
+
+  await startVisualProbe(page, regions)
+  await trigger.click()
+  await expect(trigger).toHaveAttribute("aria-expanded", "false")
+  await page.waitForTimeout(500)
+  const collapsed = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(testInfo, "shell-collapse", collapsed, plan)
+})
+
+test("expands and collapses a completed context group without overlap", async ({ page }, testInfo) => {
+  const ids = [
+    "prt_interaction_01_read",
+    "prt_interaction_02_glob",
+    "prt_interaction_03_grep",
+    "prt_interaction_04_list",
+  ]
+  const group = `[data-timeline-part-ids="${ids.join(",")}"]`
+  const followingID = "prt_interaction_context_following"
+  await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([
+        toolPart(ids[0]!, "read", "completed", { filePath: "src/a.ts" }),
+        toolPart(ids[1]!, "glob", "completed", { path: ".", pattern: "**/*.ts" }),
+        toolPart(ids[2]!, "grep", "completed", { path: ".", pattern: "stable" }),
+        toolPart(ids[3]!, "list", "completed", { path: "src" }),
+        textPart(followingID, "Following context expansion"),
+      ]),
+    ],
+    cpuRate: 4,
+    seedHistory: true,
+  })
+  const trigger = page.locator(`${group} [data-slot="collapsible-trigger"]`)
+  await waitForVisualSettle(page, [group, `[data-timeline-part-id="${followingID}"]`])
+  for (const [name, expanded] of [
+    ["context-expand", true],
+    ["context-collapse", false],
+    ["context-reexpand", true],
+  ] as const) {
+    const regions = defineVisualRegions({
+      context: { selector: group, closest: '[data-timeline-row="AssistantPart"]' },
+      following: {
+        selector: `[data-timeline-part-id="${followingID}"]`,
+        closest: '[data-timeline-row="AssistantPart"]',
+      },
+    })
+    await startVisualProbe(page, regions)
+    await trigger.click()
+    await expect(trigger).toHaveAttribute("aria-expanded", String(expanded))
+    await page.waitForTimeout(500)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(
+      testInfo,
+      name,
+      trace,
+      visualPlan(regions, [
+        { type: "required", regions: ["context", "following"] },
+        { type: "unique", regions: ["context", "following"] },
+        { type: "stable", regions: ["context", "following"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxPositionReversals: 0 },
+        { type: "label-stability", regions: "all" },
+        { type: "preserve-bottom-anchor" },
+        { type: "flow", regions: ["context", "following"] },
+      ]),
+    )
+  }
+})
+
+test("expands and collapses an edit diff without moving twice", async ({ page }, testInfo) => {
+  const editID = "prt_interaction_edit"
+  const followingID = "prt_interaction_edit_following"
+  await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([
+        toolPart(
+          editID,
+          "edit",
+          "completed",
+          { filePath: "src/edit.ts" },
+          {
+            metadata: {
+              filediff: {
+                file: "src/edit.ts",
+                additions: 40,
+                deletions: 40,
+                before: source(40, false),
+                after: source(40, true),
+              },
+            },
+          },
+        ),
+        textPart(followingID, "Following edit expansion"),
+      ]),
+    ],
+    settings: { editToolPartsExpanded: false },
+    cpuRate: 4,
+    seedHistory: true,
+  })
+  const trigger = page.locator(`[data-timeline-part-id="${editID}"] [data-slot="collapsible-trigger"]`).first()
+  await waitForVisualSettle(page, [`[data-timeline-part-id="${editID}"]`, `[data-timeline-part-id="${followingID}"]`])
+  const regions = defineVisualRegions({
+    edit: { selector: `[data-timeline-part-id="${editID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await trigger.click()
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  await page.waitForTimeout(900)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "edit-expand",
+    trace,
+    visualPlan(regions, [
+      { type: "required", regions: ["edit", "following"] },
+      { type: "unique", regions: ["edit", "following"] },
+      { type: "stable", regions: ["edit", "following"] },
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all", maxPositionReversals: 0, maxReversals: 1 },
+      { type: "label-stability", regions: "all" },
+      { type: "preserve-bottom-anchor" },
+      { type: "flow", regions: ["edit", "following"] },
+    ]),
+  )
+})
+
+test("shows all and expands historical diff summary without overlap", async ({ page }, testInfo) => {
+  const firstUser = userMessage(undefined, {
+    summary: {
+      diffs: Array.from({ length: 12 }, (_, index) => ({
+        file: `src/diff-${index}.ts`,
+        additions: 1,
+        deletions: 1,
+        patch: `@@ -1 +1 @@\n-export const value = ${index}\n+export const value = ${index + 1}`,
+      })),
+    },
+  })
+  const nextUserID = "msg_2000_diff_interaction_user"
+  await setupTimeline(page, {
+    messages: [
+      firstUser,
+      assistantMessage(),
+      userMessage(undefined, { id: nextUserID, created: 1700000010000 }),
+      assistantMessage([], {
+        id: "msg_2001_diff_interaction_assistant",
+        parentID: nextUserID,
+        created: 1700000011000,
+      }),
+    ],
+    cpuRate: 4,
+  })
+  const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+  await scroller.evaluate((element) => (element.scrollTop = 0))
+  const diff = page.locator('[data-timeline-row="DiffSummary"]')
+  const following = page.locator(`[data-message-id="${nextUserID}"]`).first()
+  await expect(diff).toBeVisible()
+  const regions = defineVisualRegions({
+    diff: { selector: '[data-timeline-row="DiffSummary"]' },
+    following: { selector: `[data-message-id="${nextUserID}"]` },
+  })
+  await startVisualProbe(page, regions)
+  await page.getByText(/show all/i).click()
+  await page.waitForTimeout(500)
+  await diff.locator('[data-slot="session-turn-diff-trigger"]').first().click()
+  await page.waitForTimeout(900)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "diff-summary-expand",
+    trace,
+    visualPlan(regions, [
+      { type: "required", regions: ["diff", "following"] },
+      { type: "unique", regions: ["diff", "following"] },
+      { type: "stable", regions: ["diff", "following"] },
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all", maxPositionReversals: 1, maxReversals: 2 },
+      { type: "label-stability", regions: "all" },
+      { type: "flow", regions: ["diff", "following"] },
+    ]),
+  )
+})
+
+function lines(count: number) {
+  return Array.from({ length: count }, (_, index) => `line ${index + 1}`).join("\n")
+}
+
+function source(count: number, changed: boolean) {
+  return Array.from(
+    { length: count },
+    (_, index) => `export const value${index} = ${changed ? index + 1 : index}\n`,
+  ).join("")
+}
@@ -0,0 +1,157 @@
+import { expect, test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  mapVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantMessage,
+  completedAssistantInfo,
+  messageUpdated,
+  partDelta,
+  partUpdated,
+  reasoningPart,
+  setupTimeline,
+  shell,
+  status,
+  textPart,
+  userMessage,
+  waitForVisualSettle,
+} from "./fixture"
+
+test.describe("timeline visual lifecycle stability", () => {
+  test("streams empty, short, and long parallel shells to staggered completion", async ({ page }, testInfo) => {
+    test.setTimeout(180_000)
+    const ids = ["prt_parallel_01_empty", "prt_parallel_02_short", "prt_parallel_03_long"] as const
+    const initial = ids.map((id) => shell(id, "running"))
+    const followingID = "prt_parallel_04_following"
+    const assistant = assistantMessage([...initial, textPart(followingID, "Following all parallel shells.")], {
+      completed: false,
+    })
+    const timeline = await setupTimeline(page, {
+      messages: [userMessage(), assistant],
+      settings: { shellToolPartsExpanded: true, showReasoningSummaries: true },
+      cpuRate: 4,
+      eventRetry: 24,
+      seedHistory: true,
+    })
+    await timeline.send(status("busy"), 150)
+    for (const id of ids) await timeline.waitForPart(id)
+    const scroller = page.locator(".scroll-view__viewport", {
+      has: page.locator('[data-timeline-row="AssistantPart"]'),
+    })
+    await scroller.evaluate((element) => (element.scrollTop = element.scrollHeight))
+    const regions = defineVisualRegions({
+      prt_shell_empty: shellRegion(ids[0]),
+      prt_shell_short: shellRegion(ids[1]),
+      prt_shell_long: shellRegion(ids[2]),
+      following: shellRegion(followingID),
+    })
+    await waitForVisualSettle(page, [`[data-timeline-part-id="${followingID}"]`])
+    await startVisualProbe(page, regions)
+    await timeline.sendAll([
+      { event: partUpdated(shell(ids[0]!, "completed", "")), delay: 180 },
+      { event: partUpdated(shell(ids[2]!, "running", lines(10))), delay: 70 },
+      { event: partUpdated(shell(ids[1]!, "running", lines(2))), delay: 110 },
+      { event: partUpdated(shell(ids[2]!, "running", lines(25))), delay: 80 },
+      { event: partUpdated(shell(ids[1]!, "completed", lines(2))), delay: 260 },
+      { event: partUpdated(shell(ids[2]!, "running", lines(50))), delay: 100 },
+      { event: partUpdated(shell(ids[2]!, "completed", lines(50))), delay: 450 },
+      { event: messageUpdated(completedAssistantInfo(assistant.info)), delay: 100 },
+      { event: status("idle"), delay: 700 },
+    ])
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(
+      testInfo,
+      "parallel-shells",
+      trace,
+      visualPlan(
+        regions,
+        [
+          { type: "required", regions: ["prt_shell_empty", "prt_shell_short", "prt_shell_long", "following"] },
+          { type: "unique", regions: ["prt_shell_empty", "prt_shell_short", "prt_shell_long"] },
+          { type: "stable", regions: ["prt_shell_empty", "prt_shell_short", "prt_shell_long", "following"] },
+          { type: "opacity", regions: "all" },
+          { type: "continuity", regions: "all" },
+          { type: "motion", regions: "all", maxPositionReversals: 0, maxReversals: 4 },
+          { type: "label-stability", regions: "all" },
+          { type: "preserve-bottom-anchor" },
+          { type: "flow", regions: ["prt_shell_empty", "prt_shell_short", "prt_shell_long", "following"] },
+        ],
+        { perMarker: true },
+      ),
+    )
+    await expect(page.locator(`[data-timeline-part-id="${ids[2]}"] [data-slot="bash-pre"]`)).toContainText("line 50")
+
+    const short = page.locator(`[data-timeline-part-id="${ids[1]}"]`)
+    await short.locator('[data-slot="collapsible-trigger"]').click()
+    await expect(short.locator('[data-slot="collapsible-trigger"]')).toHaveAttribute("aria-expanded", "false")
+    await timeline.send(partUpdated(textPart("prt_late_sibling", "A later sibling rerender.")), 250)
+    await expect(short.locator('[data-slot="collapsible-trigger"]')).toHaveAttribute("aria-expanded", "false")
+  })
+
+  test("replaces thinking with streamed reasoning and text without a blank visible turn", async ({
+    page,
+  }, testInfo) => {
+    const reasoningID = "prt_reasoning_visible"
+    const textID = "prt_streamed_text"
+    const assistant = assistantMessage([], { completed: false })
+    const timeline = await setupTimeline(page, {
+      messages: [userMessage(), assistant],
+      settings: { showReasoningSummaries: true },
+      cpuRate: 4,
+    })
+    await timeline.send(status("busy"), 120)
+    await expect(page.locator('[data-timeline-row="Thinking"]')).toBeVisible()
+
+    const regions = defineVisualRegions({
+      thinking: { selector: '[data-timeline-row="Thinking"]' },
+      reasoning: {
+        selector: `[data-timeline-part-id="${reasoningID}"]`,
+        closest: '[data-timeline-row="AssistantPart"]',
+      },
+      text: { selector: `[data-timeline-part-id="${textID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    })
+    await startVisualProbe(page, regions)
+    await timeline.send(partUpdated(reasoningPart(reasoningID, "")), 100)
+    await expect(page.locator(`[data-timeline-part-id="${reasoningID}"]`)).toHaveCount(0)
+    await timeline.send(partUpdated(reasoningPart(reasoningID, "## Planning\n\nChecking the visible timeline.")), 160)
+    await timeline.waitForPart(reasoningID)
+    await expect(page.locator('[data-timeline-row="Thinking"]')).toHaveCount(0)
+    await timeline.send(partUpdated(textPart(textID, "Starting")), 100)
+    await timeline.send(partDelta(textID, " **stable"), 90)
+    await timeline.send(partDelta(textID, " output** with `code` and [a link"), 130)
+    await timeline.send(partDelta(textID, "](https://example.com)."), 220)
+    await timeline.send(messageUpdated(completedAssistantInfo(assistant.info)), 120)
+    await timeline.send(status("idle"), 500)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(
+      testInfo,
+      "reasoning-text-handoff",
+      trace,
+      visualPlan(regions, [
+        { type: "required", regions: ["reasoning", "text"] },
+        { type: "continuous-any", regions: ["thinking", "reasoning", "text"] },
+        { type: "unique", regions: ["reasoning", "text"] },
+        { type: "stable", regions: ["reasoning", "text"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxReversals: 4 },
+        { type: "label-stability", regions: "all" },
+        { type: "flow", regions: ["reasoning", "text"] },
+      ]),
+    )
+    await expect(page.locator(`[data-timeline-part-id="${textID}"]`)).toContainText("stable output")
+  })
+})
+
+function lines(count: number) {
+  return Array.from({ length: count }, (_, index) => `line ${index + 1}`).join("\n")
+}
+
+function shellRegion(id: string) {
+  return { selector: `[data-timeline-part-id="${id}"]`, closest: '[data-timeline-row="AssistantPart"]' }
+}
@@ -0,0 +1,75 @@
+import { expect, test } from "@playwright/test"
+import {
+  analyzeVisualObservations,
+  defineVisualRegions,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import { assistantMessage, setupTimeline, textPart, userMessage } from "./fixture"
+
+test("detects blanking caused by ancestor opacity", async ({ page }) => {
+  const partID = "prt_oracle_ancestor_opacity"
+  await setupTimeline(page, { messages: [userMessage(), assistantMessage([textPart(partID, "Visible content")])] })
+  const row = page.locator(`[data-timeline-part-id="${partID}"]`).first()
+  const regions = defineVisualRegions({
+    content: { selector: `[data-timeline-part-id="${partID}"]` },
+  })
+  await startVisualProbe(page, regions)
+  await row.evaluate((element) => {
+    element.parentElement!.style.opacity = "0"
+  })
+  await page.waitForTimeout(50)
+  await row.evaluate((element) => {
+    element.parentElement!.style.opacity = "1"
+  })
+  await page.waitForTimeout(50)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  const issues = analyzeVisualObservations(
+    trace.samples,
+    visualPlan(regions, [
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all" },
+      { type: "label-stability", regions: "all" },
+    ]),
+  )
+
+  expect(issues.some((issue) => issue.includes("blanked between visible frames"))).toBe(true)
+})
+
+test("detects root opacity when probing descendant opacity", async ({ page }) => {
+  const partID = "prt_oracle_descendant_opacity"
+  await setupTimeline(page, { messages: [userMessage(), assistantMessage([textPart(partID, "Visible content")])] })
+  const row = page.locator(`[data-timeline-part-id="${partID}"]`).first()
+  await row.evaluate((element) => {
+    element.innerHTML = '<span data-probe-opacity="true">Visible content</span>'
+  })
+  const regions = defineVisualRegions({
+    content: {
+      selector: `[data-timeline-part-id="${partID}"]`,
+      opacitySelectors: ['[data-probe-opacity="true"]'],
+    },
+  })
+  await startVisualProbe(page, regions)
+  await row.evaluate((element) => {
+    ;(element as HTMLElement).style.opacity = "0"
+  })
+  await page.waitForTimeout(50)
+  await row.evaluate((element) => {
+    ;(element as HTMLElement).style.opacity = "1"
+  })
+  await page.waitForTimeout(50)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  const issues = analyzeVisualObservations(
+    trace.samples,
+    visualPlan(regions, [
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all" },
+      { type: "label-stability", regions: "all" },
+    ]),
+  )
+
+  expect(issues.some((issue) => issue.includes("blanked between visible frames"))).toBe(true)
+})
@@ -0,0 +1,17 @@
+import config from "../playwright.config"
+
+export default {
+  ...config,
+  testDir: ".",
+  testMatch: "**/*.spec.ts",
+  outputDir: "../../test-results/timeline-stability",
+  reporter: [["html", { outputFolder: "../../playwright-report/timeline-stability", open: "never" }], ["line"]],
+  retries: 0,
+  workers: 1,
+  use: {
+    ...config.use,
+    trace: "retain-on-failure",
+    screenshot: "only-on-failure",
+    video: "retain-on-failure",
+  },
+}
@@ -0,0 +1,319 @@
+import { expect, test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  shell,
+  textPart,
+  userMessage,
+  type TimelineMessage,
+} from "./fixture"
+
+test("does not reverse visible rows when the user wheels during shell remeasurement", async ({ page }, testInfo) => {
+  const shellID = "prt_wheel_01_shell"
+  const followingID = "prt_wheel_02_following"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      ...history(12),
+      userMessage(),
+      assistantMessage([shell(shellID, "running"), textPart(followingID, "Following wheel interaction")], {
+        completed: false,
+      }),
+    ],
+    settings: { shellToolPartsExpanded: true },
+    cpuRate: 4,
+    reducedMotion: true,
+    seedHistory: true,
+  })
+  const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+  const regions = defineVisualRegions({
+    shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(partUpdated(shell(shellID, "running", lines(30))), 80)
+  await scroller.evaluate((element) =>
+    element.dispatchEvent(new WheelEvent("wheel", { bubbles: true, cancelable: true, deltaY: -180 })),
+  )
+  await scroller.evaluate((element) => (element.scrollTop -= 180))
+  await timeline.send(partUpdated(shell(shellID, "running", lines(50))), 250)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(testInfo, "wheel-during-resize", trace, rowPairPlan(regions, 1))
+})
+
+test("does not pull a keyboard-scrolled user during shell remeasurement", async ({ page }, testInfo) => {
+  const shellID = "prt_keyboard_01_shell"
+  const followingID = "prt_keyboard_02_following"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      ...history(12),
+      userMessage(),
+      assistantMessage([shell(shellID, "running"), textPart(followingID, "Following keyboard interaction")], {
+        completed: false,
+      }),
+    ],
+    settings: { shellToolPartsExpanded: true },
+    cpuRate: 4,
+  })
+  const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+  await scroller.focus()
+  for (let index = 0; index < 3; index++) {
+    await scroller.press("PageUp")
+    await page.waitForTimeout(250)
+  }
+  await expect
+    .poll(() => scroller.evaluate((element) => element.scrollHeight - element.clientHeight - element.scrollTop), {
+      timeout: 20_000,
+    })
+    .toBeGreaterThan(80)
+  await page.waitForFunction(() => {
+    const root = [...document.querySelectorAll<HTMLElement>(".scroll-view__viewport")].find((element) =>
+      element.querySelector("[data-timeline-row]"),
+    )
+    if (!root) return false
+    return new Promise<boolean>((resolve) => {
+      const top = root.scrollTop
+      requestAnimationFrame(() => requestAnimationFrame(() => resolve(Math.abs(root.scrollTop - top) <= 0.5)))
+    })
+  })
+  const anchor = await scroller.evaluate((element) => {
+    const view = element.getBoundingClientRect()
+    return [...element.querySelectorAll<HTMLElement>("[data-timeline-key]")].find((row) => {
+      const rect = row.getBoundingClientRect()
+      return rect.top >= view.top + 40 && rect.bottom <= view.bottom - 40
+    })?.dataset.timelineKey
+  })
+  expect(anchor).toBeTruthy()
+  const regions = defineVisualRegions({
+    anchor: { selector: `[data-timeline-key="${anchor}"]` },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(partUpdated(shell(shellID, "running", lines(50))), 400)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(testInfo, "keyboard-during-resize", trace, anchorPlan(regions))
+})
+
+test("tracks keyboard scrolling from a focused timeline descendant", async ({ page }, testInfo) => {
+  const shellID = "prt_descendant_keyboard_01_shell"
+  const timeline = await setupTimeline(page, {
+    messages: [...history(12), userMessage(), assistantMessage([shell(shellID, "completed", lines(5))])],
+    settings: { shellToolPartsExpanded: false },
+    cpuRate: 4,
+    reducedMotion: true,
+  })
+  const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+  const row = page.locator(`[data-timeline-part-id="${shellID}"]`).first()
+  const trigger = page.locator(`[data-timeline-part-id="${shellID}"] [data-slot="collapsible-trigger"]`)
+  await row.evaluate((element) => element.setAttribute("tabindex", "0"))
+  await row.focus()
+  for (let index = 0; index < 3; index++) {
+    await row.press("PageUp")
+    await page.waitForTimeout(250)
+  }
+  await expect
+    .poll(() => scroller.evaluate((element) => element.scrollHeight - element.clientHeight - element.scrollTop))
+    .toBeGreaterThan(5)
+  const anchor = await scroller.evaluate((element) => {
+    const view = element.getBoundingClientRect()
+    return [...element.querySelectorAll<HTMLElement>("[data-timeline-key]")].find((row) => {
+      const rect = row.getBoundingClientRect()
+      return rect.top >= view.top + 40 && rect.bottom <= view.bottom - 40
+    })?.dataset.timelineKey
+  })
+  expect(anchor).toBeTruthy()
+  const regions = defineVisualRegions({
+    anchor: { selector: `[data-timeline-key="${anchor}"]` },
+  })
+  await startVisualProbe(page, regions)
+  await trigger.click()
+  await page.waitForTimeout(300)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(testInfo, "descendant-keyboard-resize", trace, anchorPlan(regions))
+})
+
+test("does not claim keyboard scrolling owned by a nested scrollable", async ({ page }) => {
+  const shellID = "prt_nested_keyboard_shell"
+  await setupTimeline(page, {
+    messages: [userMessage(), assistantMessage([shell(shellID, "completed", lines(50))])],
+    settings: { shellToolPartsExpanded: true },
+    cpuRate: 4,
+    reducedMotion: true,
+    seedHistory: true,
+  })
+  const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+  const nested = page.locator(`[data-timeline-part-id="${shellID}"] [data-scrollable]`)
+  await nested.evaluate((element) => (element.scrollTop = element.scrollHeight))
+  await nested.focus()
+  await page.waitForFunction(() => {
+    const root = [...document.querySelectorAll<HTMLElement>(".scroll-view__viewport")].find((element) =>
+      element.querySelector("[data-timeline-row]"),
+    )
+    if (!root) return false
+    return new Promise<boolean>((resolve) => {
+      const top = root.scrollTop
+      requestAnimationFrame(() => requestAnimationFrame(() => resolve(Math.abs(root.scrollTop - top) <= 0.5)))
+    })
+  })
+  const before = await scroller.evaluate((element) => element.scrollTop)
+  const nestedBefore = await nested.evaluate((element) => element.scrollTop)
+  await nested.press("PageUp")
+  await page.waitForTimeout(300)
+  expect(await scroller.evaluate((element) => element.scrollTop)).toBe(before)
+  expect(await nested.evaluate((element) => element.scrollTop)).toBeLessThan(nestedBefore)
+
+  await nested.evaluate((element) => (element.scrollTop = 0))
+  await scroller.evaluate((element) => (element.scrollTop = Math.min(300, element.scrollHeight - element.clientHeight)))
+  const boundaryBefore = await scroller.evaluate((element) => element.scrollTop)
+  expect(boundaryBefore).toBeGreaterThan(0)
+  await nested.press("PageUp")
+  await expect.poll(() => scroller.evaluate((element) => element.scrollTop)).toBeLessThan(boundaryBefore)
+
+  const nonOverflowing = page.locator(`[data-timeline-part-id="${shellID}"]`).first()
+  await nonOverflowing.evaluate((element) => {
+    element.setAttribute("data-scrollable", "")
+    element.setAttribute("tabindex", "0")
+  })
+  await nonOverflowing.focus()
+  const nonOverflowBefore = await scroller.evaluate((element) => element.scrollTop)
+  await nonOverflowing.press("PageUp")
+  await expect.poll(() => scroller.evaluate((element) => element.scrollTop)).toBeLessThan(nonOverflowBefore)
+})
+
+test("jump to latest lands on stable final rows after offscreen growth", async ({ page }, testInfo) => {
+  const shellID = "prt_jump_01_shell"
+  const followingID = "prt_jump_02_following"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      ...history(20),
+      userMessage(),
+      assistantMessage([shell(shellID, "running"), textPart(followingID, "Latest visible row")], { completed: false }),
+    ],
+    settings: { shellToolPartsExpanded: true },
+    cpuRate: 4,
+  })
+  const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+  await scroller.evaluate(
+    (element) => (element.scrollTop = Math.max(0, element.scrollHeight - element.clientHeight - 600)),
+  )
+  await timeline.send(partUpdated(shell(shellID, "running", lines(50))), 300)
+  const regions = defineVisualRegions({
+    shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await page.getByRole("button", { name: /Jump to latest/i }).click()
+  await expect(page.locator(`[data-timeline-part-id="${followingID}"]`)).toBeVisible()
+  await page.waitForTimeout(600)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "jump-latest",
+    trace,
+    visualPlan(regions, [
+      { type: "required", regions: ["shell", "following"] },
+      { type: "unique", regions: ["shell", "following"] },
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all", maxPositionReversals: 1 },
+      { type: "label-stability", regions: "all" },
+      { type: "acquire-bottom-anchor" },
+      { type: "flow", regions: ["shell", "following"] },
+    ]),
+  )
+})
+
+test("handles a single row taller than the viewport", async ({ page }, testInfo) => {
+  const shellID = "prt_tall_01_shell"
+  const followingID = "prt_tall_02_following"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([shell(shellID, "running"), textPart(followingID, "After tall row")], { completed: false }),
+    ],
+    settings: { shellToolPartsExpanded: true },
+    viewport: { width: 900, height: 360 },
+    cpuRate: 4,
+    seedHistory: true,
+  })
+  const regions = defineVisualRegions({
+    shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(partUpdated(shell(shellID, "completed", lines(100))), 700)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "taller-than-viewport",
+    trace,
+    visualPlan(regions, [
+      { type: "required", regions: ["shell", "following"] },
+      { type: "unique", regions: ["shell", "following"] },
+      { type: "stable", regions: ["shell", "following"] },
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all", maxPositionReversals: 0 },
+      { type: "label-stability", regions: "all" },
+      { type: "preserve-bottom-anchor" },
+      { type: "flow", regions: ["shell", "following"] },
+    ]),
+  )
+})
+
+function history(count: number): TimelineMessage[] {
+  return Array.from({ length: count }, (_, index) => {
+    const prefix = `msg_${String(index).padStart(4, "0")}_scroll`
+    const userID = `${prefix}_a_user`
+    return [
+      userMessage(undefined, { id: userID, created: 1690000000000 + index * 10_000 }),
+      assistantMessage(
+        [textPart(`prt_${String(index).padStart(4, "0")}_scroll`, `History ${index}. ${"content ".repeat(30)}`)],
+        {
+          id: `${prefix}_b_assistant`,
+          parentID: userID,
+          created: 1690000001000 + index * 10_000,
+        },
+      ),
+    ]
+  }).flat()
+}
+
+function lines(count: number) {
+  return Array.from({ length: count }, (_, index) => `line ${index + 1}`).join("\n")
+}
+
+function rowPairPlan(
+  regions: Record<"shell" | "following", { selector: string; closest?: string }>,
+  maxPositionReversals: number,
+) {
+  return visualPlan(regions, [
+    { type: "required", regions: ["shell", "following"] },
+    { type: "unique", regions: ["shell", "following"] },
+    { type: "stable", regions: ["shell", "following"] },
+    { type: "opacity", regions: "all" },
+    { type: "continuity", regions: "all" },
+    { type: "motion", regions: "all", maxPositionReversals },
+    { type: "label-stability", regions: "all" },
+    { type: "flow", regions: ["shell", "following"] },
+  ])
+}
+
+function anchorPlan(regions: Record<"anchor", { selector: string; closest?: string }>) {
+  return visualPlan(regions, [
+    { type: "required", regions: ["anchor"] },
+    { type: "unique", regions: ["anchor"] },
+    { type: "stable", regions: ["anchor"] },
+    { type: "fixed", regions: ["anchor"] },
+    { type: "opacity", regions: "all" },
+    { type: "continuity", regions: "all" },
+    { type: "motion", regions: "all", maxPositionReversals: 0 },
+    { type: "label-stability", regions: "all" },
+  ])
+}
@@ -0,0 +1,255 @@
+import { test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  shell,
+  textPart,
+  userMessage,
+  waitForVisualSettle,
+} from "./fixture"
+
+const profiles = [
+  {
+    name: "empty running to completed",
+    updates: [{ state: "completed" as const, output: "", delay: 350 }],
+  },
+  {
+    name: "50 lines arriving incrementally",
+    updates: [
+      { state: "running" as const, output: lines(1), delay: 100 },
+      { state: "running" as const, output: lines(10), delay: 160 },
+      { state: "running" as const, output: lines(25), delay: 90 },
+      { state: "running" as const, output: lines(50), delay: 220 },
+      { state: "completed" as const, output: lines(50), delay: 500 },
+    ],
+  },
+  {
+    name: "wide ANSI and CRLF output",
+    updates: [
+      {
+        state: "running" as const,
+        output: Array.from({ length: 20 }, (_, index) => `\u001b[32mline ${index}\u001b[0m ${"wide-".repeat(30)}`).join(
+          "\r\n",
+        ),
+        delay: 240,
+      },
+      {
+        state: "completed" as const,
+        output: Array.from({ length: 20 }, (_, index) => `line ${index} ${"wide-".repeat(30)}`).join("\n"),
+        delay: 500,
+      },
+    ],
+  },
+] as const
+
+for (const profile of profiles) {
+  test(`keeps rows stable for shell ${profile.name}`, async ({ page }, testInfo) => {
+    const shellID = `prt_matrix_${profiles.indexOf(profile)}_01_shell`
+    const followingID = `prt_matrix_${profiles.indexOf(profile)}_02_following`
+    const timeline = await setupTimeline(page, {
+      messages: [
+        userMessage(),
+        assistantMessage([shell(shellID, "running"), textPart(followingID, "Following shell row")], {
+          completed: false,
+        }),
+      ],
+      settings: { shellToolPartsExpanded: true },
+      cpuRate: 4,
+      seedHistory: true,
+    })
+    const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+    await scroller.evaluate((element) => (element.scrollTop = element.scrollHeight))
+    await waitForVisualSettle(page, [
+      `[data-timeline-part-id="${shellID}"]`,
+      `[data-timeline-part-id="${followingID}"]`,
+    ])
+    const regions = defineVisualRegions({
+      shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+      following: {
+        selector: `[data-timeline-part-id="${followingID}"]`,
+        closest: '[data-timeline-row="AssistantPart"]',
+      },
+    })
+    await startVisualProbe(page, regions)
+    for (const update of profile.updates) {
+      await timeline.send(partUpdated(shell(shellID, update.state, update.output)), update.delay)
+    }
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(
+      testInfo,
+      `shell-${profiles.indexOf(profile)}`,
+      trace,
+      visualPlan(
+        regions,
+        [
+          { type: "required", regions: ["shell", "following"] },
+          { type: "unique", regions: ["shell", "following"] },
+          { type: "stable", regions: ["shell", "following"] },
+          { type: "opacity", regions: "all" },
+          { type: "continuity", regions: "all" },
+          { type: "motion", regions: "all", maxPositionReversals: 0, maxReversals: 1 },
+          { type: "label-stability", regions: "all" },
+          { type: "preserve-bottom-anchor" },
+          { type: "flow", regions: ["shell", "following"] },
+        ],
+        { perMarker: true },
+      ),
+    )
+  })
+}
+
+test("keeps following row stable when a collapsed shell receives 50 lines", async ({ page }, testInfo) => {
+  const shellID = "prt_matrix_collapsed_01_shell"
+  const followingID = "prt_matrix_collapsed_02_following"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([shell(shellID, "running"), textPart(followingID, "Following collapsed shell")], {
+        completed: false,
+      }),
+    ],
+    settings: { shellToolPartsExpanded: false },
+    cpuRate: 4,
+    seedHistory: true,
+  })
+  await waitForVisualSettle(page, [`[data-timeline-part-id="${shellID}"]`, `[data-timeline-part-id="${followingID}"]`])
+  const regions = defineVisualRegions({
+    shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(partUpdated(shell(shellID, "running", lines(50))), 240)
+  await timeline.send(partUpdated(shell(shellID, "completed", lines(50))), 500)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "collapsed-shell",
+    trace,
+    visualPlan(
+      regions,
+      [
+        { type: "required", regions: ["shell", "following"] },
+        { type: "unique", regions: ["shell", "following"] },
+        { type: "stable", regions: ["shell", "following"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: ["following"], maxPositionReversals: 0 },
+        { type: "label-stability", regions: "all" },
+        { type: "flow", regions: ["shell", "following"] },
+      ],
+      { perMarker: true },
+    ),
+  )
+})
+
+test("keeps rows stable when a running shell becomes an error", async ({ page }, testInfo) => {
+  const shellID = "prt_matrix_error_01_shell"
+  const followingID = "prt_matrix_error_02_following"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([shell(shellID, "running", lines(10)), textPart(followingID, "Following failed shell")], {
+        completed: false,
+      }),
+    ],
+    settings: { shellToolPartsExpanded: true },
+    cpuRate: 4,
+    seedHistory: true,
+  })
+  await waitForVisualSettle(page, [`[data-timeline-part-id="${shellID}"]`, `[data-timeline-part-id="${followingID}"]`])
+  const regions = defineVisualRegions({
+    shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(
+    partUpdated({
+      ...shell(shellID, "error"),
+      state: {
+        status: "error",
+        input: { command: `echo ${shellID}` },
+        error: "Command failed after output",
+        metadata: {},
+        time: { start: 1700000001000, end: 1700000002000 },
+      },
+    }),
+    500,
+  )
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "shell-error",
+    trace,
+    visualPlan(
+      regions,
+      [
+        { type: "required", regions: ["shell", "following"] },
+        { type: "unique", regions: ["shell", "following"] },
+        { type: "stable", regions: ["shell", "following"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: ["following"], maxPositionReversals: 0 },
+        { type: "label-stability", regions: "all" },
+        { type: "preserve-bottom-anchor" },
+        { type: "flow", regions: ["shell", "following"] },
+      ],
+      { perMarker: true },
+    ),
+  )
+})
+
+test("keeps rows stable when later text arrives before shell output", async ({ page }, testInfo) => {
+  const shellID = "prt_late_text_01_shell"
+  const followingID = "prt_late_text_02_following"
+  const timeline = await setupTimeline(page, {
+    messages: [userMessage(), assistantMessage([shell(shellID, "running")], { completed: false })],
+    settings: { shellToolPartsExpanded: true },
+    cpuRate: 4,
+    seedHistory: true,
+  })
+  await waitForVisualSettle(page, [`[data-timeline-part-id="${shellID}"]`])
+  const regions = defineVisualRegions({
+    shell: { selector: `[data-timeline-part-id="${shellID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: {
+      selector: `[data-timeline-part-id="${followingID}"]`,
+      closest: '[data-timeline-row="AssistantPart"]',
+    },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(partUpdated(textPart(followingID, "Later assistant content arrived before shell output.")), 240)
+  await timeline.send(partUpdated(shell(shellID, "running", lines(20))), 300)
+  await timeline.send(partUpdated(shell(shellID, "completed", lines(20))), 600)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "late-text-before-shell-output",
+    trace,
+    visualPlan(
+      regions,
+      [
+        { type: "required", regions: ["shell", "following"] },
+        { type: "unique", regions: ["shell", "following"] },
+        { type: "stable", regions: ["shell"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxPositionReversals: 0 },
+        { type: "label-stability", regions: "all" },
+        { type: "preserve-bottom-anchor" },
+        { type: "flow", regions: ["shell", "following"] },
+      ],
+      { perMarker: true },
+    ),
+  )
+})
+
+function lines(count: number) {
+  return Array.from({ length: count }, (_, index) => `line ${index + 1}`).join("\n")
+}
@@ -0,0 +1,106 @@
+import { expect, test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantMessage,
+  partUpdated,
+  session,
+  sessionID,
+  setupTimeline,
+  textPart,
+  toolPart,
+  userMessage,
+} from "./fixture"
+
+test("adds a task child-session link without replacing the task row", async ({ page }, testInfo) => {
+  const taskID = "prt_task_link"
+  const childID = "ses_task_child"
+  const input = { description: "Inspect child", subagent_type: "explore" }
+  const timeline = await setupTimeline(page, {
+    messages: [userMessage(), assistantMessage([toolPart(taskID, "task", "running", input)], { completed: false })],
+    sessions: [session(), session({ id: childID, parentID: sessionID, title: "Inspect child" })],
+    cpuRate: 4,
+  })
+  const regions = defineVisualRegions({
+    task: { selector: `[data-timeline-part-id="${taskID}"] [data-slot="collapsible-trigger"]` },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(
+    partUpdated(toolPart(taskID, "task", "completed", input, { metadata: { sessionId: childID } })),
+    500,
+  )
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "task-link",
+    trace,
+    visualPlan(regions, [
+      { type: "required", regions: ["task"] },
+      { type: "unique", regions: ["task"] },
+      { type: "stable", regions: ["task"] },
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all", maxPositionReversals: 0 },
+      { type: "label-stability", regions: "all" },
+    ]),
+  )
+  await expect(
+    page.locator(`a[href$="/session/${childID}"]`, { has: page.locator('[data-component="task-tool-card"]') }),
+  ).toBeVisible()
+})
+
+test("changes generic tool arguments without replacing the row", async ({ page }, testInfo) => {
+  const toolID = "prt_generic_mutation"
+  const followingID = "prt_generic_mutation_following"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage(
+        [
+          toolPart(toolID, "mcp_probe", "running", { target: "one", count: 1 }),
+          textPart(followingID, "Following generic tool"),
+        ],
+        { completed: false },
+      ),
+    ],
+    cpuRate: 4,
+  })
+  const regions = defineVisualRegions({
+    tool: { selector: `[data-timeline-part-id="${toolID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(
+    partUpdated(toolPart(toolID, "mcp_probe", "running", { target: "two", count: 2, mode: "deep" })),
+    200,
+  )
+  await timeline.send(
+    partUpdated(toolPart(toolID, "mcp_probe", "completed", { target: "two", count: 2, mode: "deep" })),
+    400,
+  )
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "generic-mutation",
+    trace,
+    visualPlan(
+      regions,
+      [
+        { type: "required", regions: ["tool", "following"] },
+        { type: "unique", regions: ["tool", "following"] },
+        { type: "stable", regions: ["tool", "following"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxPositionReversals: 0 },
+        { type: "label-stability", regions: "all" },
+        { type: "flow", regions: ["tool", "following"] },
+      ],
+      { perMarker: true },
+    ),
+  )
+})
@@ -0,0 +1,198 @@
+import { expect, test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantMessage,
+  directory,
+  partUpdated,
+  session,
+  sessionID,
+  setupTimeline,
+  status,
+  textPart,
+  toolPart,
+  userMessage,
+} from "./fixture"
+
+test.describe("timeline tool state stability", () => {
+  test("moves lightweight tools through pending, running, and completed without replacing rows", async ({
+    page,
+  }, testInfo) => {
+    const ids = ["webfetch", "websearch", "task", "skill", "custom"] as const
+    const inputs = {
+      webfetch: { url: "https://example.com/docs" },
+      websearch: { query: "timeline stability" },
+      task: { description: "Inspect timeline", subagent_type: "explore" },
+      skill: { name: "stability" },
+      custom: { target: "timeline", depth: 2 },
+    }
+    const names = { webfetch: "webfetch", websearch: "websearch", task: "task", skill: "skill", custom: "mcp_probe" }
+    const questionID = "prt_state_question"
+    const todoID = "prt_state_todo"
+    const initial = [
+      ...ids.map((id) => toolPart(`prt_state_${id}`, names[id], "pending", inputs[id])),
+      toolPart(questionID, "question", "pending", questionInput()),
+      toolPart(todoID, "todowrite", "pending", { todos: [{ content: "Hidden", status: "pending" }] }),
+      textPart("prt_state_following", "Following lightweight tools"),
+    ]
+    const childID = "ses_timeline_child"
+    const timeline = await setupTimeline(page, {
+      messages: [userMessage(), assistantMessage(initial, { completed: false })],
+      sessions: [session(), session({ id: childID, parentID: sessionID, title: "Inspect timeline" })],
+      cpuRate: 4,
+    })
+    await timeline.send(status("busy"), 120)
+    for (const id of ids) await timeline.waitForPart(`prt_state_${id}`)
+    await expect(page.locator(`[data-timeline-part-id="${questionID}"]`)).toHaveCount(0)
+    await expect(page.locator(`[data-timeline-part-id="${todoID}"]`)).toHaveCount(0)
+
+    const regionIDs = [
+      "prt_state_webfetch",
+      "prt_state_websearch",
+      "prt_state_task",
+      "prt_state_skill",
+      "prt_state_custom",
+    ] as const
+    const regions = defineVisualRegions({
+      prt_state_webfetch: toolRegion(regionIDs[0]),
+      prt_state_websearch: toolRegion(regionIDs[1]),
+      prt_state_task: toolRegion(regionIDs[2]),
+      prt_state_skill: toolRegion(regionIDs[3]),
+      prt_state_custom: toolRegion(regionIDs[4]),
+    })
+    await startVisualProbe(page, regions)
+    for (const [index, id] of ids.entries()) {
+      await timeline.send(
+        partUpdated(toolPart(`prt_state_${id}`, names[id], "running", inputs[id])),
+        [80, 240, 100, 360, 140][index],
+      )
+    }
+    for (const [index, id] of ["skill", "webfetch", "custom", "task", "websearch"].entries()) {
+      const key = id as (typeof ids)[number]
+      const metadata = key === "task" ? { sessionId: childID } : key === "websearch" ? { provider: "exa" } : {}
+      const output = key === "websearch" ? "Result https://example.com/result" : "Completed"
+      await timeline.send(
+        partUpdated(toolPart(`prt_state_${key}`, names[key], "completed", inputs[key], { metadata, output })),
+        [110, 70, 280, 130, 420][index],
+      )
+    }
+    await timeline.send(
+      partUpdated(
+        toolPart(questionID, "question", "completed", questionInput(), { metadata: { answers: [["Keep it stable"]] } }),
+      ),
+      350,
+    )
+    await timeline.waitForPart(questionID)
+    await timeline.send(status("idle"), 500)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(
+      testInfo,
+      "lightweight-tools",
+      trace,
+      visualPlan(regions, [
+        { type: "required", regions: regionIDs },
+        { type: "unique", regions: regionIDs },
+        { type: "stable", regions: regionIDs },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxReversals: 4 },
+        { type: "label-stability", regions: "all" },
+      ]),
+    )
+    await expect(page.locator(`[data-timeline-part-id="${questionID}"]`)).toContainText("Keep it stable")
+    await expect(page.locator(`[data-timeline-part-id="${todoID}"]`)).toHaveCount(0)
+    await expect(
+      page.locator(`a[href$="/session/${childID}"]`, { has: page.locator('[data-component="task-tool-card"]') }),
+    ).toBeVisible()
+    await expect(page.getByRole("button", { name: /Exa Web Search/ })).toBeVisible()
+  })
+
+  test("keeps an expanded mixed context group stable through staggered completion and error", async ({
+    page,
+  }, testInfo) => {
+    const ids = ["prt_ctx_01_read", "prt_ctx_02_glob", "prt_ctx_03_grep", "prt_ctx_04_list"]
+    const tools = ["read", "glob", "grep", "list"]
+    const inputs = [
+      { filePath: "src/a.ts", offset: 0, limit: 120 },
+      { path: directory, pattern: "**/*.ts" },
+      { path: directory, pattern: "stability", include: "*.ts" },
+      { path: "src" },
+    ]
+    const context = ids.map((id, index) => toolPart(id, tools[index]!, "pending", inputs[index]!))
+    const timeline = await setupTimeline(page, {
+      messages: [
+        userMessage(),
+        assistantMessage([...context, textPart("prt_ctx_following", "Following context")], { completed: false }),
+      ],
+      cpuRate: 4,
+    })
+    await timeline.send(status("busy"), 100)
+    const groupSelector = `[data-timeline-part-ids="${ids.join(",")}"]`
+    const group = page.locator(groupSelector)
+    await expect(group).toBeVisible()
+    await group.locator('[data-slot="collapsible-trigger"]').click()
+    await expect(group.locator('[data-slot="collapsible-trigger"]')).toHaveAttribute("aria-expanded", "true")
+
+    const regions = defineVisualRegions({
+      status: {
+        selector: `${groupSelector} [data-component="tool-status-title"]`,
+        opacitySelectors: ['[data-slot="tool-status-active"]', '[data-slot="tool-status-done"]'],
+      },
+      context: { selector: groupSelector, closest: '[data-timeline-row="AssistantPart"]' },
+      following: {
+        selector: '[data-timeline-part-id="prt_ctx_following"]',
+        closest: '[data-timeline-row="AssistantPart"]',
+      },
+    })
+    await startVisualProbe(page, regions)
+    for (const [index, delay] of [90, 260, 70, 380].entries()) {
+      await timeline.send(partUpdated(toolPart(ids[index]!, tools[index]!, "running", inputs[index]!)), delay)
+    }
+    await timeline.send(partUpdated(toolPart(ids[1]!, tools[1]!, "completed", inputs[1]!)), 130)
+    await timeline.send(partUpdated(toolPart(ids[3]!, tools[3]!, "completed", inputs[3]!)), 210)
+    await timeline.send(
+      partUpdated(toolPart(ids[0]!, tools[0]!, "error", inputs[0]!, { error: "Read interrupted" })),
+      110,
+    )
+    await timeline.send(partUpdated(toolPart(ids[2]!, tools[2]!, "completed", inputs[2]!)), 250)
+    await expect(group.locator('[data-component="tool-status-title"]')).toHaveAttribute("aria-label", "Explored")
+    await timeline.send(status("idle"), 700)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    await reportVisualStability(
+      testInfo,
+      "mixed-context",
+      trace,
+      visualPlan(regions, [
+        { type: "required", regions: ["context", "following"] },
+        { type: "unique", regions: ["context"] },
+        { type: "stable", regions: ["context"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxReversals: 4 },
+        { type: "label-stability", regions: "all" },
+        { type: "flow", regions: ["context", "following"] },
+      ]),
+    )
+    await expect(group.locator('[data-component="tool-status-title"]')).toHaveAttribute("aria-label", "Explored")
+    await expect(group.locator('[data-slot="collapsible-trigger"]')).toHaveAttribute("aria-expanded", "true")
+    await group.locator('[data-slot="collapsible-trigger"]').click()
+    await expect(group.locator('[data-slot="collapsible-trigger"]')).toHaveAttribute("aria-expanded", "false")
+    await timeline.send(partUpdated(textPart("prt_ctx_late_sibling", "Later sibling content")), 200)
+    await expect(group.locator('[data-slot="collapsible-trigger"]')).toHaveAttribute("aria-expanded", "false")
+    await group.locator('[data-slot="collapsible-trigger"]').click()
+    await expect(group.locator('[data-slot="collapsible-trigger"]')).toHaveAttribute("aria-expanded", "true")
+  })
+})
+
+function questionInput() {
+  return { questions: [{ header: "Stability", question: "Keep it stable?", options: [] }] }
+}
+
+function toolRegion(id: string) {
+  return { selector: `[data-timeline-part-id="${id}"]`, closest: '[data-timeline-row="AssistantPart"]' }
+}
@@ -0,0 +1,272 @@
+import { expect, test } from "@playwright/test"
+import {
+  defineVisualRegions,
+  reportVisualStability,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../../utils/visual-stability"
+import {
+  assistantID,
+  assistantMessage,
+  completedAssistantInfo,
+  event,
+  messageUpdated,
+  partDelta,
+  partUpdated,
+  setupTimeline,
+  shell,
+  status,
+  textPart,
+  toolPart,
+  userMessage,
+} from "./fixture"
+
+test("keeps unchanged siblings stable while a middle part is inserted and removed", async ({ page }, testInfo) => {
+  const firstID = "prt_mutation_01_first"
+  const middleID = "prt_mutation_02_middle"
+  const lastID = "prt_mutation_03_last"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([textPart(firstID, "First stable row"), textPart(lastID, "Last stable row")], {
+        completed: false,
+      }),
+    ],
+    cpuRate: 4,
+  })
+  const regions = defineVisualRegions({
+    first: { selector: `[data-timeline-part-id="${firstID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    last: { selector: `[data-timeline-part-id="${lastID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(partUpdated(textPart(middleID, "Inserted middle row. ".repeat(12))), 350)
+  await expect(page.locator(`[data-timeline-part-id="${middleID}"]`)).toBeVisible()
+  await timeline.send(
+    event("message.part.removed", { sessionID: "ses_timeline_stability", messageID: assistantID, partID: middleID }),
+    500,
+  )
+  await expect(page.locator(`[data-timeline-part-id="${middleID}"]`)).toHaveCount(0)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(testInfo, "middle-insert-remove", trace, stablePairPlan(regions, 1))
+})
+
+test("streams text through growth, canonical replacement, and completion", async ({ page }, testInfo) => {
+  const textID = "prt_text_reconcile"
+  const followingID = "prt_text_reconcile_following"
+  const assistant = assistantMessage([textPart(textID, "Starting"), textPart(followingID, "Following text row")], {
+    completed: false,
+  })
+  const timeline = await setupTimeline(page, { messages: [userMessage(), assistant], cpuRate: 4 })
+  const regions = defineVisualRegions({
+    text: { selector: `[data-timeline-part-id="${textID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    following: { selector: `[data-timeline-part-id="${followingID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(partDelta(textID, " streamed content"), 100)
+  await timeline.send(partDelta(textID, "\n\n- item one\n- item two\n- item three"), 180)
+  await timeline.send(partUpdated(textPart(textID, "Canonical replacement with a shorter final paragraph.")), 200)
+  await timeline.send(messageUpdated(completedAssistantInfo(assistant.info)), 500)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "text-reconcile",
+    trace,
+    visualPlan(regions, [
+      { type: "required", regions: ["text", "following"] },
+      { type: "unique", regions: ["text", "following"] },
+      { type: "stable", regions: ["text", "following"] },
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all", maxPositionReversals: 1, maxReversals: 2 },
+      { type: "label-stability", regions: "all" },
+      { type: "preserve-bottom-anchor" },
+      { type: "flow", regions: ["text", "following"] },
+    ]),
+  )
+})
+
+test("inserts a completed question between stable rows", async ({ page }, testInfo) => {
+  const firstID = "prt_question_01_first"
+  const questionID = "prt_question_02_hidden"
+  const lastID = "prt_question_03_last"
+  const input = { questions: [{ header: "Choice", question: "Keep stable?", options: [] }] }
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage(
+        [
+          textPart(firstID, "Before question"),
+          toolPart(questionID, "question", "running", input),
+          textPart(lastID, "After question"),
+        ],
+        { completed: false },
+      ),
+    ],
+    cpuRate: 4,
+  })
+  await expect(page.locator(`[data-timeline-part-id="${questionID}"]`)).toHaveCount(0)
+  const regions = defineVisualRegions({
+    first: { selector: `[data-timeline-part-id="${firstID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+    last: { selector: `[data-timeline-part-id="${lastID}"]`, closest: '[data-timeline-row="AssistantPart"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(
+    partUpdated(toolPart(questionID, "question", "completed", input, { metadata: { answers: [["Yes"]] } })),
+    600,
+  )
+  await expect(page.locator(`[data-timeline-part-id="${questionID}"]`)).toBeVisible()
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(testInfo, "question-insert", trace, stablePairPlan(regions, 0))
+})
+
+test("replaces thinking with an assistant error without a blank turn", async ({ page }, testInfo) => {
+  const assistant = assistantMessage([], { completed: false })
+  const timeline = await setupTimeline(page, { messages: [userMessage(), assistant], cpuRate: 4 })
+  await timeline.send(status("busy"), 150)
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toBeVisible()
+  const regions = defineVisualRegions({
+    thinking: { selector: '[data-timeline-row="Thinking"]' },
+    error: { selector: '[data-timeline-row="Error"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(
+    messageUpdated({
+      ...assistant.info,
+      error: { name: "APIError", data: { message: "Provider failed visibly", isRetryable: false } },
+    }),
+    500,
+  )
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toHaveCount(0)
+  await expect(page.locator('[data-timeline-row="Error"]')).toContainText("Provider failed visibly")
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "thinking-error",
+    trace,
+    visualPlan(regions, [
+      { type: "required", regions: ["thinking", "error"] },
+      { type: "continuous-any", regions: ["thinking", "error"] },
+      { type: "unique", regions: ["thinking", "error"] },
+      { type: "opacity", regions: "all" },
+      { type: "continuity", regions: "all" },
+      { type: "motion", regions: "all" },
+      { type: "label-stability", regions: "all" },
+    ]),
+  )
+})
+
+test("updates retry attempts and long provider messages without remounting the retry row", async ({
+  page,
+}, testInfo) => {
+  const timeline = await setupTimeline(page, {
+    messages: [userMessage(), assistantMessage([], { completed: false })],
+    cpuRate: 4,
+  })
+  await timeline.send(status("retry", 1), 120)
+  await expect(page.locator('[data-timeline-row="Retry"]')).toBeVisible()
+  const regions = defineVisualRegions({
+    retry: { selector: '[data-timeline-row="Retry"]' },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(
+    event("session.status", {
+      sessionID: "ses_timeline_stability",
+      status: {
+        type: "retry",
+        attempt: 2,
+        message: "A very long provider retry message ".repeat(8),
+        next: Date.now() + 10_000,
+      },
+    }),
+    300,
+  )
+  await timeline.send(status("retry", 3), 300)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "retry-evolution",
+    trace,
+    visualPlan(
+      regions,
+      [
+        { type: "required", regions: ["retry"] },
+        { type: "unique", regions: ["retry"] },
+        { type: "stable", regions: ["retry"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxPositionReversals: 0 },
+        { type: "label-stability", regions: "all" },
+      ],
+      { perMarker: true },
+    ),
+  )
+})
+
+test("reducer-hardening: removes a historical turn one message at a time without moving a visible lower anchor twice", async ({
+  page,
+}, testInfo) => {
+  const removeUserID = "msg_0500_remove_user"
+  const removeAssistantID = "msg_0501_remove_assistant"
+  const anchorUserID = "msg_2000_anchor_user"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(undefined, { id: removeUserID, created: 1690000000000 }),
+      assistantMessage([textPart("prt_remove_text", "Removed historical content. ".repeat(15))], {
+        id: removeAssistantID,
+        parentID: removeUserID,
+        created: 1690000001000,
+      }),
+      userMessage(undefined, { id: anchorUserID, created: 1700000000000 }),
+      assistantMessage([textPart("prt_anchor_text", "Visible anchor response")], {
+        id: "msg_2001_anchor_assistant",
+        parentID: anchorUserID,
+        created: 1700000001000,
+      }),
+    ],
+    cpuRate: 4,
+  })
+  const regions = defineVisualRegions({
+    anchor: { selector: `[data-timeline-row="UserMessage"][data-message-id="${anchorUserID}"]` },
+  })
+  await startVisualProbe(page, regions)
+  await timeline.send(
+    event("message.removed", { sessionID: "ses_timeline_stability", messageID: removeAssistantID }),
+    200,
+  )
+  await timeline.send(event("message.removed", { sessionID: "ses_timeline_stability", messageID: removeUserID }), 500)
+  const trace = await stopVisualProbe<keyof typeof regions>(page)
+  await reportVisualStability(
+    testInfo,
+    "historical-turn-remove",
+    trace,
+    visualPlan(
+      regions,
+      [
+        { type: "required", regions: ["anchor"] },
+        { type: "unique", regions: ["anchor"] },
+        { type: "stable", regions: ["anchor"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all", maxPositionReversals: 0 },
+        { type: "label-stability", regions: "all" },
+      ],
+      { perMarker: true },
+    ),
+  )
+})
+
+function stablePairPlan(
+  regions: Record<"first" | "last", { selector: string; closest?: string }>,
+  maxPositionReversals: number,
+) {
+  return visualPlan(regions, [
+    { type: "required", regions: ["first", "last"] },
+    { type: "unique", regions: ["first", "last"] },
+    { type: "stable", regions: ["first", "last"] },
+    { type: "opacity", regions: "all" },
+    { type: "continuity", regions: "all" },
+    { type: "motion", regions: "all", maxPositionReversals },
+    { type: "label-stability", regions: "all" },
+  ])
+}
@@ -45,7 +45,7 @@ export async function installStressSessionTabs(page: Page, input?: { draftID?: s
        }),
      )
      localStorage.setItem(
-        "opencode.global.dat:tabs",
+        "opencode.window.browser.dat:tabs",
        JSON.stringify([
          ...sessionIDs.map((sessionId) => ({
            type: "session",
@@ -0,0 +1,392 @@
+import { expect, test } from "bun:test"
+import {
+  analyzeVisualStability,
+  analyzeVisualStabilityByMarker,
+  type VisualStabilityTrace,
+} from "../../utils/visual-stability"
+import { analyzeVisualObservations } from "../../utils/visual-stability/analyzer"
+import { legacyVisualPlan, visualPlan, type VisualInvariant } from "../../utils/visual-stability/invariant"
+import { defineVisualRegions, mapVisualRegions } from "../../utils/visual-stability/regions"
+
+function trace(samples: VisualStabilityTrace["samples"]): VisualStabilityTrace {
+  return { markers: [], samples }
+}
+
+test("accepts continuous visible motion", () => {
+  expect(
+    analyzeVisualStability(
+      trace([
+        frame(0, region({ width: 80, bottom: 40 }), region({ top: 40, bottom: 60 })),
+        frame(16, region({ width: 75, bottom: 45 }), region({ top: 45, bottom: 65 })),
+        frame(32, region({ width: 70, bottom: 50 }), region({ top: 50, bottom: 70 })),
+      ]),
+      { flow: ["changing", "following"] },
+    ),
+  ).toEqual([])
+})
+
+test("reports repeated geometry reversals", () => {
+  const issues = analyzeVisualStability(
+    trace([
+      frame(0, region({ width: 80 })),
+      frame(16, region({ width: 60 })),
+      frame(32, region({ width: 78 })),
+      frame(48, region({ width: 62 })),
+    ]),
+  )
+
+  expect(issues.some((issue) => issue.includes("changing width reversed 2 times"))).toBe(true)
+})
+
+test("reports visible blanking, label reversal, and overlap", () => {
+  const issues = analyzeVisualStability(
+    trace([
+      frame(0, region({ label: "Exploring", opacity: 1, bottom: 40 }), region({ top: 40, bottom: 60 })),
+      frame(16, region({ label: "Explored", opacity: 0.2, bottom: 50 }), region({ top: 49, bottom: 69 })),
+      frame(32, region({ label: "Exploring", opacity: 1, bottom: 50 }), region({ top: 50, bottom: 70 })),
+    ]),
+    { flow: ["changing", "following"] },
+  )
+
+  expect(issues.some((issue) => issue.includes("opacity fell to 0.2"))).toBe(true)
+  expect(issues.some((issue) => issue.includes("label reverted"))).toBe(true)
+  expect(issues.some((issue) => issue.includes("overlapped following by 1px"))).toBe(true)
+})
+
+test("reports duplicate regions and unexpected remounts", () => {
+  const issues = analyzeVisualStability(
+    trace([frame(0, region({ node: 1 })), frame(16, region({ node: 2, count: 2 })), frame(32, region({ node: 2 }))]),
+    { stable: ["changing"], unique: ["changing"] },
+  )
+
+  expect(issues.some((issue) => issue.includes("changing appeared 2 times"))).toBe(true)
+  expect(issues.some((issue) => issue.includes("changing remounted"))).toBe(true)
+})
+
+test("reports bottom anchor loss but permits movement while scrolled away", () => {
+  const anchored = analyzeVisualStability(
+    trace([
+      { at: 0, regions: { changing: region() }, viewport: viewport(0) },
+      { at: 16, regions: { changing: region() }, viewport: viewport(24) },
+    ]),
+    { preserveBottomAnchor: true },
+  )
+  const away = analyzeVisualStability(
+    trace([
+      { at: 0, regions: { changing: region() }, viewport: viewport(80) },
+      { at: 16, regions: { changing: region() }, viewport: viewport(104) },
+    ]),
+    { preserveBottomAnchor: true },
+  )
+
+  expect(anchored.some((issue) => issue.includes("bottom anchor moved to 24px"))).toBe(true)
+  expect(away).toEqual([])
+})
+
+test("reports up down up movement while preserving a bottom anchor", () => {
+  const issues = analyzeVisualStability(
+    trace([
+      { at: 0, regions: { changing: region({ top: 200, bottom: 240 }) }, viewport: viewport(0) },
+      { at: 16, regions: { changing: region({ top: 180, bottom: 220 }) }, viewport: viewport(0) },
+      { at: 32, regions: { changing: region({ top: 196, bottom: 236 }) }, viewport: viewport(0) },
+      { at: 48, regions: { changing: region({ top: 176, bottom: 216 }) }, viewport: viewport(0) },
+    ]),
+    { preserveBottomAnchor: true, maxPositionReversals: 0 },
+  )
+
+  expect(issues.some((issue) => issue.includes("changing top reversed 2 times"))).toBe(true)
+  expect(issues.some((issue) => issue.includes("changing bottom reversed 2 times"))).toBe(true)
+})
+
+test("accepts monotonic upward movement while preserving a bottom anchor", () => {
+  expect(
+    analyzeVisualStability(
+      trace([
+        { at: 0, regions: { changing: region({ top: 200, bottom: 240 }) }, viewport: viewport(0) },
+        { at: 16, regions: { changing: region({ top: 190, bottom: 230 }) }, viewport: viewport(0) },
+        { at: 32, regions: { changing: region({ top: 180, bottom: 220 }) }, viewport: viewport(0) },
+      ]),
+      { preserveBottomAnchor: true, maxPositionReversals: 0 },
+    ),
+  ).toEqual([])
+})
+
+test("ignores overlap entirely outside the clipped timeline viewport", () => {
+  expect(
+    analyzeVisualStability(
+      trace([
+        {
+          at: 0,
+          regions: {
+            changing: region({ top: -200, bottom: -100 }),
+            following: region({ top: -150, bottom: -50 }),
+          },
+          viewport: viewport(0),
+        },
+      ]),
+      { flow: ["changing", "following"] },
+    ),
+  ).toEqual([])
+})
+
+test("reports visible anchor movement while allowing virtual scrollbar movement", () => {
+  const issues = analyzeVisualStability(
+    trace([
+      { at: 0, regions: { anchor: region({ top: 100, bottom: 120 }) }, viewport: { ...viewport(100), scrollTop: 40 } },
+      { at: 16, regions: { anchor: region({ top: 100, bottom: 120 }) }, viewport: { ...viewport(120), scrollTop: 60 } },
+    ]),
+    { fixed: ["anchor"] },
+  )
+
+  expect(issues).toEqual([])
+
+  const moved = analyzeVisualStability(
+    trace([
+      { at: 0, regions: { anchor: region({ top: 100, bottom: 120 }) }, viewport: viewport(100) },
+      { at: 16, regions: { anchor: region({ top: 112, bottom: 132 }) }, viewport: viewport(100) },
+    ]),
+    { fixed: ["anchor"] },
+  )
+  expect(moved.some((issue) => issue.includes("anchor moved 12px in the viewport"))).toBe(true)
+})
+
+test("analyzes each marked event independently", () => {
+  const input: VisualStabilityTrace = {
+    markers: [
+      { at: 10, label: "grow" },
+      { at: 40, label: "shrink" },
+    ],
+    samples: [
+      frame(0, region({ top: 100 })),
+      frame(16, region({ top: 90 })),
+      frame(32, region({ top: 80 })),
+      frame(48, region({ top: 90 })),
+      frame(64, region({ top: 100 })),
+    ],
+  }
+
+  expect(analyzeVisualStability(input, { maxPositionReversals: 0 })).toContain("changing top reversed 1 times")
+  expect(
+    analyzeVisualStabilityByMarker(input, {
+      maxPositionReversals: 0,
+      motion: ["changing"],
+      aggregateMotion: false,
+    }),
+  ).toEqual([])
+})
+
+test("reports cross-event motion reversals by default", () => {
+  const input: VisualStabilityTrace = {
+    markers: [
+      { at: 10, label: "up" },
+      { at: 40, label: "down" },
+    ],
+    samples: [
+      frame(0, region({ top: 100 })),
+      frame(16, region({ top: 90 })),
+      frame(32, region({ top: 80 })),
+      frame(48, region({ top: 90 })),
+      frame(64, region({ top: 100 })),
+    ],
+  }
+
+  expect(analyzeVisualStabilityByMarker(input, { maxPositionReversals: 0 })).toContain("changing top reversed 1 times")
+})
+
+test("reports regions rendered in the wrong flow order", () => {
+  const issues = analyzeVisualStability(
+    trace([frame(0, region({ top: 100, bottom: 120 }), region({ top: 60, bottom: 80 }))]),
+    { flow: ["changing", "following"] },
+  )
+
+  expect(issues.some((issue) => issue.includes("changing rendered after following"))).toBe(true)
+})
+
+test("uses painted bounds instead of clipped layout overflow", () => {
+  expect(
+    analyzeVisualStability(
+      trace([
+        frame(
+          0,
+          region({ top: 100, bottom: 140, height: 40, layoutTop: 100, layoutBottom: 300 }),
+          region({ top: 140, bottom: 180 }),
+        ),
+      ]),
+      { flow: ["changing", "following"] },
+    ),
+  ).toEqual([])
+})
+
+test("does not report disappearance when a present row moves outside the viewport", () => {
+  expect(
+    analyzeVisualStability(
+      trace([
+        frame(0, region({ visible: true })),
+        frame(16, region({ visible: false, inViewport: false, top: -100, bottom: -80 })),
+        frame(32, region({ visible: true })),
+      ]),
+    ),
+  ).toEqual([])
+})
+
+test("reports an in-viewport transparent frame between visible frames", () => {
+  const issues = analyzeVisualStability(
+    trace([
+      frame(0, region()),
+      frame(16, region({ visible: false, opacity: 0, inViewport: true })),
+      frame(32, region()),
+    ]),
+  )
+
+  expect(issues.some((issue) => issue.includes("blanked between visible frames"))).toBe(true)
+})
+
+test("reports an in-viewport display-none frame between visible frames", () => {
+  const issues = analyzeVisualStability(
+    trace([
+      frame(0, region()),
+      frame(16, region({ visible: false, width: 0, height: 0, inViewport: true, cssHidden: true })),
+      frame(32, region()),
+    ]),
+  )
+
+  expect(issues.some((issue) => issue.includes("blanked between visible frames"))).toBe(true)
+})
+
+test("can limit motion analysis to unaffected regions", () => {
+  expect(
+    analyzeVisualStability(
+      trace([
+        frame(0, region({ height: 20 }), region()),
+        frame(16, region({ height: 40 }), region()),
+        frame(32, region({ height: 30 }), region()),
+      ]),
+      { motion: ["following"] },
+    ),
+  ).toEqual([])
+})
+
+test("reports a blank frame across replacement surfaces", () => {
+  const issues = analyzeVisualStability(
+    {
+      markers: [],
+      samples: [
+        { at: 0, regions: { thinking: region(), error: region({ present: false, visible: false }) } },
+        {
+          at: 16,
+          regions: {
+            thinking: region({ present: false, visible: false }),
+            error: region({ present: false, visible: false }),
+          },
+        },
+        { at: 32, regions: { thinking: region({ present: false, visible: false }), error: region() } },
+      ],
+    },
+    { continuousAny: [["thinking", "error"]] },
+  )
+
+  expect(issues.some((issue) => issue.includes("thinking | error blanked"))).toBe(true)
+})
+
+test("reports failure to acquire the bottom anchor", () => {
+  const issues = analyzeVisualStability(
+    trace([
+      { at: 0, regions: { changing: region() }, viewport: viewport(600) },
+      { at: 16, regions: { changing: region() }, viewport: viewport(120) },
+    ]),
+    { acquireBottomAnchor: true },
+  )
+
+  expect(issues.some((issue) => issue.includes("did not acquire bottom anchor"))).toBe(true)
+})
+
+test("reports a required region that never renders", () => {
+  const issues = analyzeVisualStability(
+    trace([
+      {
+        at: 0,
+        regions: { changing: region({ present: false, visible: false }) },
+      },
+    ]),
+    { required: ["changing"] },
+  )
+
+  expect(issues).toContain("changing never rendered")
+})
+
+test("preserves typed region names while mapping definitions", () => {
+  const regions = defineVisualRegions({
+    changing: { selector: "[data-changing]" },
+    following: { selector: "[data-following]", closest: "[data-row]" },
+  })
+  const selectors = mapVisualRegions(regions, (region) => region.selector)
+
+  expect(selectors).toEqual({ changing: "[data-changing]", following: "[data-following]" })
+  const name: keyof typeof selectors = "changing"
+  expect(name).toBe("changing")
+})
+
+test("evaluates the typed invariant algebra over explicit observations", () => {
+  const regions = defineVisualRegions({
+    changing: { selector: "[data-changing]" },
+    following: { selector: "[data-following]" },
+  })
+  const invariants = [
+    { type: "required", regions: ["changing"] },
+    { type: "flow", regions: ["changing", "following"] },
+  ] satisfies VisualInvariant<keyof typeof regions>[]
+  // @ts-expect-error Plans reject names that are not in the region definition.
+  const invalid = { type: "required", regions: ["missing"] } satisfies VisualInvariant<keyof typeof regions>
+  const plan = visualPlan(regions, invariants, { perMarker: true })
+
+  expect(invalid.regions).toEqual(["missing"])
+  expect(plan.perMarker).toBe(true)
+  expect(analyzeVisualObservations([frame(0, region({ bottom: 50 }), region({ top: 49, bottom: 69 }))], plan)).toEqual([
+    "changing overlapped following by 1px at 0ms",
+  ])
+})
+
+test("legacy plan adapter preserves analyzer messages and order", () => {
+  const input = trace([
+    frame(0, region({ label: "Exploring", opacity: 1, bottom: 40 }), region({ top: 40, bottom: 60 })),
+    frame(16, region({ label: "Explored", opacity: 0.2, bottom: 50 }), region({ top: 49, bottom: 69 })),
+    frame(32, region({ label: "Exploring", opacity: 1, bottom: 50 }), region({ top: 50, bottom: 70 })),
+  ])
+  const options = { flow: ["changing", "following"], stable: ["changing"] }
+
+  expect(analyzeVisualObservations(input.samples, legacyVisualPlan(options))).toEqual(
+    analyzeVisualStability(input, options),
+  )
+})
+
+function frame(
+  at: number,
+  changing: VisualStabilityTrace["samples"][number]["regions"][string],
+  following?: VisualStabilityTrace["samples"][number]["regions"][string],
+) {
+  return { at, regions: { changing, ...(following ? { following } : {}) } }
+}
+
+function region(input: Partial<VisualStabilityTrace["samples"][number]["regions"][string]> = {}) {
+  return {
+    present: true,
+    visible: true,
+    inViewport: true,
+    top: 0,
+    bottom: 20,
+    width: 100,
+    height: 20,
+    opacity: 1,
+    count: 1,
+    node: 1,
+    label: "",
+    text: "",
+    layoutTop: input.top ?? 0,
+    layoutBottom: input.bottom ?? 20,
+    ...input,
+  }
+}
+
+function viewport(distanceFromBottom: number) {
+  return { top: 0, bottom: 400, scrollTop: 100, scrollHeight: 500, clientHeight: 400, distanceFromBottom }
+}
@@ -14,7 +14,7 @@ test("closing the active server's last tab opens the remaining server tab", asyn
      localStorage.setItem("settings.v3", JSON.stringify({ general: { newLayoutDesigns: true } }))
      localStorage.setItem("opencode.global.dat:server", JSON.stringify({ list: [serverB] }))
      localStorage.setItem(
-        "opencode.global.dat:tabs",
+        "opencode.window.browser.dat:tabs",
        JSON.stringify([
          { type: "session", server: "http://127.0.0.1:4096", sessionId: sessionA },
          { type: "session", server: serverB, sessionId: sessionB },
@@ -52,7 +52,7 @@ test("legacy session routes preserve an existing tab's server", async ({ page })
      localStorage.setItem("settings.v3", JSON.stringify({ general: { newLayoutDesigns: true } }))
      localStorage.setItem("opencode.global.dat:server", JSON.stringify({ list: [serverB] }))
      localStorage.setItem(
-        "opencode.global.dat:tabs",
+        "opencode.window.browser.dat:tabs",
        JSON.stringify([{ type: "session", server: serverB, sessionId: sessionB }]),
      )
    },
@@ -66,7 +66,7 @@ test("shows the V2 thinking level control while relevant", async ({ page }) => {
  await expect(control).toBeVisible()

  await control.locator('[data-action="prompt-model-variant"]').click()
-  const high = page.getByRole("option", { name: "high" })
+  const high = page.getByRole("menuitemradio", { name: "high" })
  await expect(high).toBeVisible()
  await page.mouse.move(0, 0)
  await expect(control).toBeVisible()
@@ -38,6 +38,29 @@ test("shows a pending question dock", async ({ page }) => {
  await expect(question.getByRole("radio", { name: /Extended/ })).toBeVisible()
  await expect(page.locator('[data-component="session-composer"]')).toHaveCount(0)

+  const rejectRequests: string[] = []
+  page.on("request", (request) => {
+    if (request.method() !== "POST") return
+    if (new URL(request.url()).pathname === "/question/question-request/reject") rejectRequests.push(request.url())
+  })
+
+  await question.locator('[data-component="icon-button"][data-icon="chevron-down"]').click()
+  await expect(question).toBeVisible()
+  await expect(question.getByText("Which implementation should be used?")).toBeVisible()
+  await expect(question.getByText("Select one answer")).toBeHidden()
+  await expect(question.getByRole("radio", { name: /Minimal/ })).toBeHidden()
+  await expect(question.getByRole("radio", { name: /Extended/ })).toBeHidden()
+  await expect(question.getByRole("button", { name: "Dismiss" })).toBeVisible()
+  await expect(question.getByRole("button", { name: "Submit" })).toBeVisible()
+  await expect(page.locator('[data-component="question-minimized-dock"]')).toHaveCount(0)
+  expect(rejectRequests).toEqual([])
+
+  await question.locator('[data-component="icon-button"][data-icon="chevron-down"]').click()
+  await expect(question).toBeVisible()
+  await expect(question.getByText("Which implementation should be used?")).toBeVisible()
+  await expect(question.getByRole("radio", { name: /Minimal/ })).toBeVisible()
+  expect(rejectRequests).toEqual([])
+
  await question.getByRole("radio", { name: /Minimal/ }).click()
  const reply = page.waitForRequest(
    (request) => request.method() === "POST" && new URL(request.url()).pathname === "/question/question-request/reply",
@@ -0,0 +1,22 @@
+import { expect, test } from "@playwright/test"
+import { assistantMessage, setupTimeline, shell, userMessage } from "../performance/timeline-stability/fixture"
+
+test("space activates a focused timeline button instead of scrolling", async ({ page }) => {
+  const shellID = "prt_space_button_shell"
+  await setupTimeline(page, {
+    messages: [userMessage(), assistantMessage([shell(shellID, "completed", lines(5))])],
+    settings: { shellToolPartsExpanded: false },
+    reducedMotion: true,
+  })
+  const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+  const trigger = page.locator(`[data-timeline-part-id="${shellID}"] [data-slot="collapsible-trigger"]`)
+  await trigger.focus()
+  const before = await scroller.evaluate((element) => element.scrollTop)
+  await trigger.press("Space")
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  expect(await scroller.evaluate((element) => element.scrollTop)).toBe(before)
+})
+
+function lines(count: number) {
+  return Array.from({ length: count }, (_, index) => `line ${index + 1}`).join("\n")
+}
@@ -1,6 +1,13 @@
 import { expect, test, type Page } from "@playwright/test"
 import { mockOpenCodeServer } from "../utils/mock-server"
 import { expectAppVisible, expectSessionTitle } from "../utils/waits"
+import {
+  analyzeVisualObservations,
+  defineVisualRegions,
+  startVisualProbe,
+  stopVisualProbe,
+  visualPlan,
+} from "../utils/visual-stability"

 const directory = "C:/OpenCode/ContextResizeRegression"
 const projectID = "proj_context_resize_regression"
@@ -36,6 +43,82 @@ test.describe("regression: session timeline context group resize", () => {
    expect(visibleOverlap).toEqual([])
    expect(samples.at(-1)?.expanded).toBe("true")
  })
+
+  test("paints a stable exploring to explored transition", async ({ page }) => {
+    const events: { directory: string; payload: Record<string, unknown> }[] = []
+    await page.setViewportSize({ width: 1400, height: 900 })
+    await mockServer(page, events, [
+      ...Array.from({ length: 8 }, (_, index) => turn(index, false)).flat(),
+      ...turn(10, true, "running"),
+    ])
+    await configurePage(page)
+
+    await page.goto(`/${base64Encode(directory)}/session/${sessionID}`)
+    await expectSessionTitle(page, title)
+    const devtools = await page.context().newCDPSession(page)
+    await devtools.send("Emulation.setCPUThrottlingRate", { rate: 4 })
+    const context = page.locator(`[data-timeline-part-ids="${contextIDs.join(",")}"]`).first()
+    await expectAppVisible(context)
+    await expect(context.locator('[data-component="tool-status-title"]')).toHaveAttribute("aria-label", "Exploring")
+
+    const contextSelector = `[data-timeline-part-ids="${contextIDs.join(",")}"]`
+    const regions = defineVisualRegions({
+      status: {
+        selector: `${contextSelector} [data-component="tool-status-title"]`,
+        opacitySelectors: ['[data-slot="tool-status-active"]', '[data-slot="tool-status-done"]'],
+      },
+      context: { selector: contextSelector, closest: '[data-timeline-row="AssistantPart"]' },
+      following: {
+        selector: `[data-timeline-part-id="${followingTextID}"]`,
+        closest: '[data-timeline-row="AssistantPart"]',
+      },
+    })
+    await startVisualProbe(page, regions)
+    for (const [index, delay] of [120, 350, 80, 500].entries()) {
+      events.push({
+        directory,
+        payload: {
+          type: "message.part.updated",
+          properties: {
+            part: contextTool(
+              contextIDs[index]!,
+              id("msg_assistant", 10),
+              ["read", "glob", "grep", "list"][index]!,
+              [
+                { filePath: "src/recent-a.ts" },
+                { path: directory, pattern: "**/*.ts" },
+                { path: directory, pattern: "Explored" },
+                { path: "src" },
+              ][index]!,
+            ),
+          },
+        },
+      })
+      await page.waitForTimeout(delay)
+    }
+
+    await expect(context.locator('[data-component="tool-status-title"]')).toHaveAttribute("aria-label", "Explored")
+    await page.waitForTimeout(700)
+    const trace = await stopVisualProbe<keyof typeof regions>(page)
+    const labels = trace.samples
+      .map((sample) => sample.regions.status?.label)
+      .filter((value): value is string => !!value)
+      .filter((value, index, all) => value !== all[index - 1])
+    const issues = analyzeVisualObservations(
+      trace.samples,
+      visualPlan(regions, [
+        { type: "required", regions: ["context", "following"] },
+        { type: "opacity", regions: "all" },
+        { type: "continuity", regions: "all" },
+        { type: "motion", regions: "all" },
+        { type: "label-stability", regions: "all" },
+        { type: "flow", regions: ["context", "following"] },
+      ]),
+    )
+
+    expect(labels).toEqual(["Exploring", "Explored"])
+    expect(issues, JSON.stringify(trace.samples, null, 2)).toEqual([])
+  })
 })

 async function configurePage(page: Page) {
@@ -128,7 +211,7 @@ async function sampleExpansion(page: Page) {
  )
 }

-function turn(index: number, target: boolean): Message[] {
+function turn(index: number, target: boolean, status: "running" | "completed" = "completed"): Message[] {
  const userID = id("msg_user", index)
  const assistantID = id("msg_assistant", index)
  return [
@@ -163,10 +246,22 @@ function turn(index: number, target: boolean): Message[] {
      },
      parts: target
        ? [
-            contextTool(contextIDs[0]!, assistantID, "read", { filePath: "src/recent-a.ts", offset: 0, limit: 120 }),
-            contextTool(contextIDs[1]!, assistantID, "glob", { path: directory, pattern: "**/*.ts" }),
-            contextTool(contextIDs[2]!, assistantID, "grep", { path: directory, pattern: "Explored", include: "*.ts" }),
-            contextTool(contextIDs[3]!, assistantID, "list", { path: "src" }),
+            contextTool(
+              contextIDs[0]!,
+              assistantID,
+              "read",
+              { filePath: "src/recent-a.ts", offset: 0, limit: 120 },
+              status,
+            ),
+            contextTool(contextIDs[1]!, assistantID, "glob", { path: directory, pattern: "**/*.ts" }, status),
+            contextTool(
+              contextIDs[2]!,
+              assistantID,
+              "grep",
+              { path: directory, pattern: "Explored", include: "*.ts" },
+              status,
+            ),
+            contextTool(contextIDs[3]!, assistantID, "list", { path: "src" }, status),
            {
              id: followingTextID,
              sessionID,
@@ -188,7 +283,13 @@ function turn(index: number, target: boolean): Message[] {
  ]
 }

-function contextTool(partID: string, messageID: string, tool: string, input: Record<string, unknown>) {
+function contextTool(
+  partID: string,
+  messageID: string,
+  tool: string,
+  input: Record<string, unknown>,
+  status: "running" | "completed" = "completed",
+) {
  return {
    id: partID,
    sessionID,
@@ -197,7 +298,7 @@ function contextTool(partID: string, messageID: string, tool: string, input: Rec
    callID: `call_${partID}`,
    tool,
    state: {
-      status: "completed",
+      status,
      input,
      output: `Completed ${tool}.\n${"detail line\n".repeat(8)}`,
      title: input.filePath || input.path || input.pattern || "completed",
@@ -207,13 +308,19 @@ function contextTool(partID: string, messageID: string, tool: string, input: Rec
  }
 }

-async function mockServer(page: Page) {
+async function mockServer(
+  page: Page,
+  events: { directory: string; payload: Record<string, unknown> }[] = [],
+  fixtureMessages = messages,
+) {
  await mockOpenCodeServer(page, {
    directory,
    project: project(),
    provider: provider(),
    sessions: [session()],
-    pageMessages: () => ({ items: messages }),
+    pageMessages: () => ({ items: fixtureMessages }),
+    events: () => events.splice(0, 1),
+    eventRetry: 50,
  })
 }

@@ -0,0 +1,31 @@
+import { expect, test } from "@playwright/test"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  toolPart,
+  userMessage,
+} from "../performance/timeline-stability/fixture"
+
+test("preserves a collapsed context group through count and status updates", async ({ page }) => {
+  const ids = ["prt_closed_01_read", "prt_closed_02_glob"]
+  const inputs = {
+    read: { filePath: "src/a.ts", offset: 0, limit: 120 },
+    glob: { path: ".", pattern: "**/*.ts" },
+  }
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage(
+        [toolPart(ids[0]!, "read", "running", inputs.read), toolPart(ids[1]!, "glob", "running", inputs.glob)],
+        { completed: false },
+      ),
+    ],
+  })
+  const group = page.locator(`[data-timeline-part-ids="${ids.join(",")}"]`)
+  const trigger = group.locator('[data-slot="collapsible-trigger"]')
+  await expect(trigger).toHaveAttribute("aria-expanded", "false")
+  await timeline.send(partUpdated(toolPart(ids[0]!, "read", "completed", inputs.read)), 100)
+  await timeline.send(partUpdated(toolPart(ids[1]!, "glob", "completed", inputs.glob)), 300)
+  await expect(trigger).toHaveAttribute("aria-expanded", "false")
+})
@@ -0,0 +1,52 @@
+import { expect, test } from "@playwright/test"
+import { assistantMessage, setupTimeline, toolPart, userMessage } from "../performance/timeline-stability/fixture"
+
+test("renders completed write content", async ({ page }) => {
+  const id = "prt_file_projection_write"
+  await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([
+        toolPart(id, "write", "completed", { filePath: "src/write.ts", content: "export const written = true\n" }),
+      ]),
+    ],
+    settings: { editToolPartsExpanded: true },
+  })
+
+  await expect(page.locator(`[data-timeline-part-id="${id}"] [data-component="write-content"]`)).toBeVisible()
+})
+
+test("renders a completed single-file patch", async ({ page }) => {
+  const id = "prt_file_projection_single_patch"
+  await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([
+        toolPart(
+          id,
+          "apply_patch",
+          "completed",
+          { files: ["src/a.ts"] },
+          {
+            metadata: {
+              files: [
+                {
+                  filePath: "src/a.ts",
+                  relativePath: "src/a.ts",
+                  type: "update",
+                  additions: 1,
+                  deletions: 1,
+                  before: "export const value = 1\n",
+                  after: "export const value = 2\n",
+                },
+              ],
+            },
+          },
+        ),
+      ]),
+    ],
+    settings: { editToolPartsExpanded: true },
+  })
+
+  await expect(page.locator(`[data-timeline-part-id="${id}"] [data-component="apply-patch-file-diff"]`)).toBeVisible()
+})
@@ -0,0 +1,94 @@
+import { expect, test } from "@playwright/test"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  toolPart,
+  userMessage,
+} from "../performance/timeline-stability/fixture"
+
+test("updates edit diagnostics without resetting manual collapse state", async ({ page }) => {
+  const editID = "prt_diagnostics_edit"
+  const base = editPart(editID, [])
+  const timeline = await setupTimeline(page, {
+    messages: [userMessage(), assistantMessage([base])],
+    settings: { editToolPartsExpanded: true },
+  })
+  const trigger = page.locator(`[data-timeline-part-id="${editID}"] [data-slot="collapsible-trigger"]`).first()
+  await trigger.click()
+  await expect(trigger).toHaveAttribute("aria-expanded", "false")
+  await timeline.send(
+    partUpdated(editPart(editID, [diagnostic("First failure", 2), diagnostic("Second failure", 4)])),
+    300,
+  )
+  await expect(trigger).toHaveAttribute("aria-expanded", "false")
+  await timeline.send(partUpdated(editPart(editID, [])), 300)
+  await expect(trigger).toHaveAttribute("aria-expanded", "false")
+})
+
+test("preserves nested patch file state through outer collapse and reopen", async ({ page }) => {
+  const patchID = "prt_nested_patch"
+  const files = [patchFile("src/a.ts", "update"), patchFile("src/b.ts", "add"), patchFile("src/old.ts", "delete")]
+  await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([
+        toolPart(
+          patchID,
+          "apply_patch",
+          "completed",
+          { files: files.map((file) => file.filePath) },
+          { metadata: { files } },
+        ),
+      ]),
+    ],
+    settings: { editToolPartsExpanded: true },
+  })
+  const wrapper = page.locator(`[data-timeline-part-id="${patchID}"]`)
+  const outer = wrapper.locator('[data-slot="collapsible-trigger"]').first()
+  const deleted = wrapper.locator('[data-scope="apply-patch"] [data-type="delete"]')
+  await deleted.getByRole("button").click()
+  await expect(deleted.getByRole("button")).toHaveAttribute("aria-expanded", "true")
+  await outer.click()
+  await expect(outer).toHaveAttribute("aria-expanded", "false")
+  await outer.click()
+  await expect(outer).toHaveAttribute("aria-expanded", "true")
+  await expect(deleted.getByRole("button")).toHaveAttribute("aria-expanded", "true")
+})
+
+function patchFile(filePath: string, type: "add" | "update" | "delete") {
+  return {
+    filePath,
+    relativePath: filePath,
+    type,
+    additions: type === "delete" ? 0 : 4,
+    deletions: type === "add" ? 0 : 3,
+    before: type === "add" ? undefined : source(false),
+    after: type === "delete" ? undefined : source(true),
+  }
+}
+
+function editPart(id: string, diagnostics: Record<string, unknown>[]) {
+  return toolPart(
+    id,
+    "edit",
+    "completed",
+    { filePath: "src/edit.ts" },
+    {
+      metadata: {
+        filediff: { file: "src/edit.ts", additions: 1, deletions: 1, before: source(false), after: source(true) },
+        diagnostics,
+      },
+    },
+  )
+}
+
+function diagnostic(message: string, line: number) {
+  return { message, severity: 1, range: { start: { line, character: 0 }, end: { line, character: 2 } } }
+}
+
+function source(changed: boolean) {
+  return Array.from({ length: 12 }, (_, index) => `export const value${index} = ${changed ? index + 1 : index}\n`).join(
+    "",
+  )
+}
@@ -0,0 +1,94 @@
+import { expect, test } from "@playwright/test"
+import {
+  assistantMessage,
+  completedAssistantInfo,
+  messageUpdated,
+  partUpdated,
+  reasoningPart,
+  setupTimeline,
+  shell,
+  status,
+  textPart,
+  userMessage,
+} from "../performance/timeline-stability/fixture"
+
+for (const expanded of [false, true]) {
+  test(`preserves shell user intent from a ${expanded ? "expanded" : "collapsed"} default`, async ({ page }) => {
+    const id = `prt_shell_default_${expanded}`
+    const timeline = await setupTimeline(page, {
+      messages: [userMessage(), assistantMessage([shell(id, "completed", lines(3))])],
+      settings: { shellToolPartsExpanded: expanded },
+    })
+    const trigger = page.locator(`[data-timeline-part-id="${id}"] [data-slot="collapsible-trigger"]`)
+    await expect(trigger).toHaveAttribute("aria-expanded", String(expanded))
+    await trigger.click()
+    await expect(trigger).toHaveAttribute("aria-expanded", String(!expanded))
+
+    await timeline.send(partUpdated(shell(id, "completed", lines(6))), 180)
+    await timeline.send(partUpdated(textPart(`prt_sibling_${expanded}`, "Sibling content")), 180)
+    await timeline.send(status("busy"), 100)
+    await timeline.send(status("idle"), 250)
+    await expect(trigger).toHaveAttribute("aria-expanded", String(!expanded))
+  })
+}
+
+test("transitions thinking and hidden reasoning through busy to idle", async ({ page }) => {
+  const reasoningID = "prt_reasoning_hidden"
+  const assistant = assistantMessage([reasoningPart(reasoningID, "## Inspecting stability")], { completed: false })
+  const timeline = await setupTimeline(page, {
+    messages: [userMessage(), assistant],
+    settings: { showReasoningSummaries: false },
+    cpuRate: 4,
+  })
+  await timeline.send(status("busy"), 150)
+
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toBeVisible()
+  await expect(page.getByText("Inspecting stability", { exact: true })).toBeVisible()
+  await expect(page.locator(`[data-timeline-part-id="${reasoningID}"]`)).toHaveCount(0)
+  await timeline.send(partUpdated(shell("prt_reasoning_shell", "running")), 160)
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toBeVisible()
+  await timeline.send(partUpdated(shell("prt_reasoning_shell", "completed", "done")), 180)
+  await timeline.send(messageUpdated(completedAssistantInfo(assistant.info)), 100)
+  await timeline.send(status("idle"), 300)
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toHaveCount(0)
+  await expect(page.locator(`[data-timeline-part-id="${reasoningID}"]`)).toHaveCount(0)
+})
+
+test("moves busy through retry and recovery to final idle content", async ({ page }) => {
+  const assistant = assistantMessage([], { completed: false })
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(undefined, {
+        summary: {
+          diffs: [
+            {
+              file: "src/retry.ts",
+              additions: 1,
+              deletions: 1,
+              patch: "@@ -1 +1 @@\n-export const retry = false\n+export const retry = true",
+            },
+          ],
+        },
+      }),
+      assistant,
+    ],
+  })
+  await timeline.send(status("busy"), 140)
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toBeVisible()
+  await expect(page.locator('[data-timeline-row="DiffSummary"]')).toHaveCount(0)
+  await timeline.send(status("retry"), 180)
+  await expect(page.locator('[data-timeline-row="Retry"]')).toBeVisible()
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toHaveCount(0)
+  await timeline.send(status("busy", 2), 180)
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toBeVisible()
+  await timeline.send(partUpdated(textPart("prt_recovered", "Recovered response")), 140)
+  await timeline.send(messageUpdated(completedAssistantInfo(assistant.info)), 100)
+  await timeline.send(status("idle"), 350)
+  await expect(page.locator('[data-timeline-row="Retry"]')).toHaveCount(0)
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toHaveCount(0)
+  await expect(page.locator('[data-timeline-row="DiffSummary"]')).toBeVisible()
+})
+
+function lines(count: number) {
+  return Array.from({ length: count }, (_, index) => `line ${index + 1}`).join("\n")
+}
@@ -0,0 +1,25 @@
+import { expect, test } from "@playwright/test"
+import { assistantMessage, setupTimeline, toolPart, userMessage } from "../performance/timeline-stability/fixture"
+
+for (const profile of [
+  { locale: "de", label: "Erkundet" },
+  { locale: "ar", label: "تم الاستكشاف" },
+] as const) {
+  test(`projects translated context status in ${profile.locale}`, async ({ page }) => {
+    const ids = [`prt_locale_${profile.locale}_01_read`, `prt_locale_${profile.locale}_02_glob`]
+    await setupTimeline(page, {
+      messages: [
+        userMessage(),
+        assistantMessage([
+          toolPart(ids[0]!, "read", "completed", { filePath: "src/a.ts" }),
+          toolPart(ids[1]!, "glob", "completed", { path: ".", pattern: "**/*.ts" }),
+        ]),
+      ],
+      locale: profile.locale,
+    })
+
+    const group = page.locator(`[data-timeline-part-ids="${ids.join(",")}"]`)
+    await expect(group.locator('[data-component="tool-status-title"]')).toHaveAttribute("aria-label", profile.label)
+    await expect(page.locator("html")).toHaveAttribute("lang", profile.locale)
+  })
+}
@@ -0,0 +1,284 @@
+import { expect, test } from "@playwright/test"
+import {
+  assistantMessage,
+  setupTimeline,
+  status,
+  toolPart,
+  userMessage,
+  userText,
+  type PartSeed,
+} from "../performance/timeline-stability/fixture"
+
+test.describe("session timeline projection", () => {
+  test("renders every admitted tool family and hides timeline-only exclusions", async ({ page }) => {
+    const parts = [
+      toolPart("prt_01_read", "read", "completed", { filePath: "src/a.ts" }),
+      toolPart("prt_02_glob", "glob", "completed", { path: ".", pattern: "**/*.ts" }),
+      toolPart("prt_03_grep", "grep", "completed", { path: ".", pattern: "value" }),
+      toolPart("prt_04_list", "list", "completed", { path: "src" }),
+      toolPart("prt_webfetch", "webfetch", "completed", { url: "https://example.com" }),
+      toolPart(
+        "prt_websearch",
+        "websearch",
+        "completed",
+        { query: "timeline stability" },
+        { output: "https://example.com/result" },
+      ),
+      toolPart("prt_task", "task", "completed", { description: "Inspect timeline", subagent_type: "explore" }),
+      toolPart(
+        "prt_bash",
+        "bash",
+        "completed",
+        { command: "printf stable" },
+        { output: "stable", title: "printf stable" },
+      ),
+      editPart("prt_edit"),
+      toolPart("prt_write", "write", "completed", { filePath: "src/new.ts", content: "export const stable = true\n" }),
+      patchPart("prt_patch"),
+      toolPart("prt_todo", "todowrite", "completed", { todos: [{ content: "Hidden", status: "pending" }] }),
+      toolPart(
+        "prt_question",
+        "question",
+        "completed",
+        { questions: [{ question: "Keep stable?", header: "Stability", options: [] }] },
+        { metadata: { answers: [["Yes"]] } },
+      ),
+      toolPart("prt_skill", "skill", "completed", { name: "stability" }),
+      toolPart("prt_custom", "custom_mcp_tool", "completed", { target: "timeline", count: 2 }),
+    ]
+    await setupTimeline(page, { messages: [userMessage(), assistantMessage(parts)] })
+
+    await expect(
+      page.locator('[data-timeline-part-ids="prt_01_read,prt_02_glob,prt_03_grep,prt_04_list"]'),
+    ).toBeVisible()
+    for (const id of [
+      "prt_webfetch",
+      "prt_websearch",
+      "prt_task",
+      "prt_bash",
+      "prt_edit",
+      "prt_write",
+      "prt_patch",
+      "prt_question",
+      "prt_skill",
+      "prt_custom",
+    ]) {
+      await expect(page.locator(`[data-timeline-part-id="${id}"]`).first(), id).toBeVisible()
+    }
+    await expect(page.locator('[data-timeline-part-id="prt_todo"]')).toHaveCount(0)
+  })
+
+  test("projects gaps, dividers, assistant parts, and errors together", async ({ page }) => {
+    const firstUser = userMessage(
+      [
+        userText("The user made the following comment regarding lines 4 through 8 of src/a.ts: Keep this stable", {
+          id: "prt_comment",
+          synthetic: true,
+          metadata: {
+            opencodeComment: {
+              path: "src/a.ts",
+              selection: { startLine: 4, startChar: 0, endLine: 8, endChar: 0 },
+              comment: "Keep this stable",
+            },
+          },
+        }),
+        userText("Continue after the comment", { id: "prt_visible_user" }),
+      ],
+      { summary: { diffs: Array.from({ length: 11 }, (_, index) => summaryDiff(index)) } },
+    )
+    const aborted = assistantMessage(
+      [
+        { id: "prt_before_abort", type: "text", text: "Before interruption" },
+        { id: "prt_compaction", type: "compaction", auto: true },
+      ],
+      {
+        id: "msg_1001_assistant_aborted",
+        error: { name: "MessageAbortedError", data: { message: "Stopped" } },
+      },
+    )
+    const failed = assistantMessage([{ id: "prt_after_abort", type: "text", text: "After interruption" }], {
+      id: "msg_1002_assistant_failed",
+      error: {
+        name: "APIError",
+        data: {
+          message: JSON.stringify({ error: { type: "provider_error", message: "Visible provider failure" } }),
+          isRetryable: false,
+        },
+      },
+      created: 1700000003000,
+    })
+    const nextUser = userMessage([userText("Second turn", { id: "prt_second_user" })], {
+      id: "msg_2000_second_user",
+      created: 1700000005000,
+    })
+    const nextAssistant = assistantMessage([{ id: "prt_second_text", type: "text", text: "Second response" }], {
+      id: "msg_2001_second_assistant",
+      parentID: "msg_2000_second_user",
+      created: 1700000006000,
+    })
+    const timeline = await setupTimeline(page, { messages: [firstUser, aborted, failed, nextUser, nextAssistant] })
+    await timeline.send(status("idle"), 100)
+    const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+    await scroller.evaluate((element) => (element.scrollTop = 0))
+
+    await expect(page.locator('[data-timeline-row="TurnDivider"]')).toHaveCount(1)
+    await expect(page.getByText("Session compacted", { exact: true })).toBeVisible()
+    await expect(page.getByText("Visible provider failure")).toBeVisible()
+    await scroller.evaluate((element) => (element.scrollTop = element.scrollHeight))
+    await expect(page.locator('[data-timeline-row="TurnGap"]')).toBeVisible()
+  })
+
+  test("renders comment strips and historical diff summary overflow", async ({ page }) => {
+    const user = userMessage(
+      [
+        userText("The user made the following comment regarding lines 4 through 8 of src/a.ts: Keep this stable", {
+          id: "prt_comment_only",
+          synthetic: true,
+          metadata: {
+            opencodeComment: {
+              path: "src/a.ts",
+              selection: { startLine: 4, startChar: 0, endLine: 8, endChar: 0 },
+              comment: "Keep this stable",
+            },
+          },
+        }),
+        userText("Continue after the comment", { id: "prt_comment_visible" }),
+      ],
+      { summary: { diffs: Array.from({ length: 11 }, (_, index) => summaryDiff(index)) } },
+    )
+    const nextUser = userMessage(undefined, { id: "msg_2000_diff_next_user", created: 1700000010000 })
+    const nextAssistant = assistantMessage([], {
+      id: "msg_2001_diff_next_assistant",
+      parentID: "msg_2000_diff_next_user",
+      created: 1700000011000,
+    })
+    await setupTimeline(page, { messages: [user, assistantMessage(), nextUser, nextAssistant] })
+    const scroller = page.locator(".scroll-view__viewport", { has: page.locator("[data-timeline-row]") })
+    await scroller.evaluate((element) => (element.scrollTop = 0))
+
+    await expect(page.locator('[data-timeline-row="CommentStrip"]')).toBeVisible()
+    await expect(page.getByText("Keep this stable", { exact: true })).toBeVisible()
+    await expect(page.locator('[data-timeline-row="DiffSummary"]')).toBeVisible()
+    await expect(page.getByText(/show all/i)).toBeVisible()
+  })
+
+  test("renders interruption independently when the turn is not compacted", async ({ page }) => {
+    const user = userMessage()
+    const before = assistantMessage([{ id: "prt_before", type: "text", text: "Before" }], {
+      id: "msg_1001_before",
+      error: { name: "MessageAbortedError", data: { message: "Stopped" } },
+    })
+    const after = assistantMessage([{ id: "prt_after", type: "text", text: "After" }], {
+      id: "msg_1002_after",
+      created: 1700000003000,
+    })
+    await setupTimeline(page, { messages: [user, before, after] })
+
+    await expect(page.getByText("Interrupted", { exact: true })).toBeVisible()
+    const rows = await page
+      .locator('[data-timeline-row="AssistantPart"], [data-timeline-row="TurnDivider"]')
+      .evaluateAll((elements) => elements.map((element) => element.getAttribute("data-timeline-row")))
+    expect(rows).toEqual(["AssistantPart", "TurnDivider", "AssistantPart"])
+  })
+
+  test("renders user image, file attachment, file reference, and agent reference", async ({ page }) => {
+    const text = "Use @explore with @src/a.ts and inspect the attachments"
+    const parts: PartSeed<"user">[] = [
+      userText(text, { id: "prt_user_rich" }),
+      {
+        id: "prt_user_image",
+        type: "file",
+        mime: "image/png",
+        filename: "pixel.png",
+        url: "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mNk+M9QDwADhgGAWjR9awAAAABJRU5ErkJggg==",
+      },
+      {
+        id: "prt_user_attachment",
+        type: "file",
+        mime: "application/json",
+        filename: "tsconfig.json",
+        url: "data:application/json;base64,e30=",
+      },
+      {
+        id: "prt_user_reference",
+        type: "file",
+        mime: "text/plain",
+        filename: "a.ts",
+        url: "src/a.ts",
+        source: { type: "file", path: "src/a.ts", text: { value: "@src/a.ts", start: 18, end: 27 } },
+      },
+      {
+        id: "prt_user_agent",
+        type: "agent",
+        name: "explore",
+        source: { value: "@explore", start: 4, end: 12 },
+      },
+    ]
+    await setupTimeline(page, { messages: [userMessage(parts), assistantMessage()] })
+
+    await expect(page.getByAltText("pixel.png")).toBeVisible()
+    await expect(page.getByText("tsconfig.json")).toBeVisible()
+    await expect(page.getByText("@src/a.ts", { exact: true })).toBeVisible()
+    await expect(page.getByText("@explore", { exact: true })).toBeVisible()
+  })
+})
+
+function editPart(id: string) {
+  return toolPart(
+    id,
+    "edit",
+    "completed",
+    { filePath: "src/a.ts" },
+    {
+      metadata: {
+        filediff: {
+          file: "src/a.ts",
+          additions: 1,
+          deletions: 1,
+          before: "export const value = 1\n",
+          after: "export const value = 2\n",
+        },
+      },
+    },
+  )
+}
+
+function patchPart(id: string) {
+  return toolPart(
+    id,
+    "apply_patch",
+    "completed",
+    { files: ["src/a.ts", "src/b.ts"] },
+    {
+      metadata: {
+        files: [
+          patchFile("src/a.ts", "update"),
+          patchFile("src/b.ts", "add"),
+          patchFile("src/old.ts", "delete"),
+          { ...patchFile("src/moved.ts", "move"), move: "src/new-place.ts" },
+        ],
+      },
+    },
+  )
+}
+
+function patchFile(filePath: string, type: "add" | "update" | "delete" | "move") {
+  return {
+    filePath,
+    relativePath: filePath,
+    type,
+    additions: type === "delete" ? 0 : 1,
+    deletions: type === "add" ? 0 : 1,
+    before: type === "add" ? undefined : "export const before = true\n",
+    after: type === "delete" ? undefined : "export const after = true\n",
+  }
+}
+
+function summaryDiff(index: number) {
+  return {
+    file: `src/diff-${index}.ts`,
+    additions: 1,
+    deletions: 1,
+    patch: `@@ -1 +1 @@\n-export const value = ${index}\n+export const value = ${index + 1}`,
+  }
+}
@@ -0,0 +1,93 @@
+import { expect, test } from "@playwright/test"
+import {
+  assistantMessage,
+  reasoningPart,
+  setupTimeline,
+  status,
+  textPart,
+  toolPart,
+  userMessage,
+} from "../performance/timeline-stability/fixture"
+
+const profiles = [
+  { name: "summaries off no reasoning", summaries: false, reasoning: "", other: false, thinking: true, body: false },
+  {
+    name: "summaries off reasoning heading",
+    summaries: false,
+    reasoning: "## Inspecting stability",
+    other: false,
+    thinking: true,
+    body: false,
+  },
+  {
+    name: "summaries off with visible tool",
+    summaries: false,
+    reasoning: "## Inspecting stability",
+    other: true,
+    thinking: true,
+    body: false,
+  },
+  { name: "summaries on no content", summaries: true, reasoning: "", other: false, thinking: true, body: false },
+  {
+    name: "summaries on blank reasoning",
+    summaries: true,
+    reasoning: "   ",
+    other: false,
+    thinking: true,
+    body: false,
+  },
+  {
+    name: "summaries on visible reasoning",
+    summaries: true,
+    reasoning: "## Inspecting stability",
+    other: false,
+    thinking: false,
+    body: true,
+  },
+  {
+    name: "summaries on visible tool no reasoning",
+    summaries: true,
+    reasoning: "",
+    other: true,
+    thinking: false,
+    body: false,
+  },
+] as const
+
+for (const profile of profiles) {
+  test(`projects busy reasoning profile ${profile.name}`, async ({ page }) => {
+    const reasoningID = `prt_reasoning_matrix_${profiles.indexOf(profile)}`
+    const parts = [
+      ...(profile.reasoning ? [reasoningPart(reasoningID, profile.reasoning)] : []),
+      ...(profile.other
+        ? [toolPart(`prt_reasoning_tool_${profiles.indexOf(profile)}`, "skill", "running", { name: "inspect" })]
+        : []),
+    ]
+    const timeline = await setupTimeline(page, {
+      messages: [userMessage(), assistantMessage(parts, { completed: false })],
+      settings: { showReasoningSummaries: profile.summaries },
+    })
+    await timeline.send(status("busy"), 150)
+
+    await expect(page.locator('[data-timeline-row="Thinking"]')).toHaveCount(profile.thinking ? 1 : 0)
+    await expect(page.locator(`[data-timeline-part-id="${reasoningID}"]`)).toHaveCount(profile.body ? 1 : 0)
+    if (!profile.summaries && profile.reasoning.trim()) {
+      await expect(page.getByText("Inspecting stability", { exact: true })).toBeVisible()
+    }
+  })
+}
+
+test("does not infer reasoning visibility from provider identity", async ({ page }) => {
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([textPart("prt_provider_text", "No reasoning payload")], { completed: false }),
+    ],
+    settings: { showReasoningSummaries: true },
+  })
+  await timeline.send(status("busy"), 150)
+
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toHaveCount(0)
+  await expect(page.locator('[data-timeline-part-id*="reasoning"]')).toHaveCount(0)
+  await expect(page.locator('[data-timeline-part-id="prt_provider_text"]')).toBeVisible()
+})
@@ -0,0 +1,43 @@
+import { expect, test } from "@playwright/test"
+import {
+  assistantMessage,
+  completedAssistantInfo,
+  messageUpdated,
+  partUpdated,
+  setupTimeline,
+  shell,
+  status,
+  textPart,
+  toolPart,
+  userMessage,
+} from "../performance/timeline-stability/fixture"
+
+test("groups singleton and separated context operations at correct boundaries", async ({ page }) => {
+  const parts = [
+    toolPart("prt_boundary_01_read", "read", "completed", { filePath: "src/a.ts" }),
+    textPart("prt_boundary_02_text", "Boundary text"),
+    toolPart("prt_boundary_03_glob", "glob", "completed", { path: ".", pattern: "**/*.ts" }),
+    toolPart("prt_boundary_04_grep", "grep", "completed", { path: ".", pattern: "stable" }),
+    shell("prt_boundary_05_shell", "completed", "done"),
+    toolPart("prt_boundary_06_list", "list", "completed", { path: "src" }),
+  ]
+  await setupTimeline(page, { messages: [userMessage(), assistantMessage(parts)] })
+
+  await expect(page.locator('[data-timeline-part-ids="prt_boundary_01_read"]')).toBeVisible()
+  await expect(page.locator('[data-timeline-part-ids="prt_boundary_03_glob,prt_boundary_04_grep"]')).toBeVisible()
+  await expect(page.locator('[data-timeline-part-ids="prt_boundary_06_list"]')).toBeVisible()
+  await expect(page.locator('[data-timeline-row="AssistantPart"]')).toHaveCount(5)
+})
+
+test("reducer-hardening: converges when idle arrives before final part and message completion", async ({ page }) => {
+  const textID = "prt_event_order_text"
+  const assistant = assistantMessage([textPart(textID, "Partial")], { completed: false })
+  const timeline = await setupTimeline(page, { messages: [userMessage(), assistant] })
+  await timeline.send(status("busy"), 100)
+  await timeline.send(status("idle"), 100)
+  await timeline.send(partUpdated(textPart(textID, "Final after early idle")), 120)
+  await timeline.send(messageUpdated(completedAssistantInfo(assistant.info)), 250)
+
+  await expect(page.locator('[data-timeline-row="Thinking"]')).toHaveCount(0)
+  await expect(page.locator(`[data-timeline-part-id="${textID}"]`)).toContainText("Final after early idle")
+})
@@ -0,0 +1,99 @@
+import { expect, test } from "@playwright/test"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  toolPart,
+  userMessage,
+} from "../performance/timeline-stability/fixture"
+
+test("renders every tool error outcome without leaking hidden tools", async ({ page }) => {
+  const ordinary = ["bash", "edit", "write", "apply_patch", "webfetch", "websearch", "task", "skill", "mcp_probe"]
+  const parts = ordinary.map((tool, index) =>
+    toolPart(`prt_error_${index}`, tool, "error", errorInput(tool), { error: `${tool} failed visibly` }),
+  )
+  parts.push(
+    toolPart("prt_question_dismissed", "question", "error", questionInput(), {
+      error: "The user dismissed this question",
+    }),
+    toolPart("prt_question_error", "question", "error", questionInput(), { error: "Question transport failed" }),
+    toolPart("prt_todo_error", "todowrite", "error", { todos: [] }, { error: "Hidden todo failure" }),
+  )
+  await setupTimeline(page, { messages: [userMessage(), assistantMessage(parts)] })
+
+  await expect(page.locator('[data-kind="tool-error-card"]')).toHaveCount(ordinary.length + 1)
+  await expect(page.getByText(/dismissed/i)).toBeVisible()
+  await expect(page.locator('[data-timeline-part-id="prt_todo_error"]')).toHaveCount(0)
+  for (let index = 0; index < ordinary.length; index++) {
+    await expect(page.locator(`[data-timeline-part-id="prt_error_${index}"]`)).toBeVisible()
+  }
+})
+
+test("transitions shell and question through running error outcomes", async ({ page }) => {
+  const shellID = "prt_transition_error_shell"
+  const questionID = "prt_transition_error_question"
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage(
+        [
+          toolPart(shellID, "bash", "pending", { command: "exit 1" }),
+          toolPart(questionID, "question", "pending", questionInput()),
+        ],
+        { completed: false },
+      ),
+    ],
+  })
+  await timeline.waitForPart(shellID)
+  await expect(page.locator(`[data-timeline-part-id="${questionID}"]`)).toHaveCount(0)
+  await timeline.send(partUpdated(toolPart(shellID, "bash", "running", { command: "exit 1" })), 120)
+  await timeline.send(partUpdated(toolPart(questionID, "question", "running", questionInput())), 180)
+  await expect(page.locator(`[data-timeline-part-id="${questionID}"]`)).toHaveCount(0)
+  await timeline.send(
+    partUpdated(toolPart(shellID, "bash", "error", { command: "exit 1" }, { error: "Command exited 1" })),
+    180,
+  )
+  await timeline.send(
+    partUpdated(
+      toolPart(questionID, "question", "error", questionInput(), { error: "The user dismissed this question" }),
+    ),
+    250,
+  )
+
+  await expect(page.locator(`[data-timeline-part-id="${shellID}"] [data-kind="tool-error-card"]`)).toBeVisible()
+  await expect(page.locator(`[data-timeline-part-id="${questionID}"]`)).toContainText(/dismissed/i)
+})
+
+test("labels all web search provider variants", async ({ page }) => {
+  const parts = [
+    toolPart(
+      "prt_search_parallel",
+      "websearch",
+      "completed",
+      { query: "parallel" },
+      { metadata: { provider: "parallel" } },
+    ),
+    toolPart("prt_search_exa", "websearch", "completed", { query: "exa" }, { metadata: { provider: "exa" } }),
+    toolPart("prt_search_generic", "websearch", "completed", { query: "generic" }),
+  ]
+  await setupTimeline(page, { messages: [userMessage(), assistantMessage(parts)] })
+
+  await expect(page.getByRole("button", { name: /Parallel Web Search/ })).toBeVisible()
+  await expect(page.getByRole("button", { name: /Exa Web Search/ })).toBeVisible()
+  await expect(page.getByRole("button", { name: /^Web Search/ })).toBeVisible()
+})
+
+function questionInput() {
+  return { questions: [{ header: "Stability", question: "Keep it stable?", options: [] }] }
+}
+
+function errorInput(tool: string) {
+  if (tool === "bash") return { command: "exit 1" }
+  if (["edit", "write"].includes(tool)) return { filePath: "src/error.ts", content: "" }
+  if (tool === "apply_patch") return { files: ["src/error.ts"] }
+  if (tool === "webfetch") return { url: "https://example.com" }
+  if (tool === "websearch") return { query: "failure" }
+  if (tool === "task") return { description: "Fail task", subagent_type: "explore" }
+  if (tool === "skill") return { name: "failure" }
+  return { target: "failure" }
+}
@@ -0,0 +1,77 @@
+import { expect, test } from "@playwright/test"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  toolPart,
+  userMessage,
+} from "../performance/timeline-stability/fixture"
+
+test("updates expanded web search links without resetting expansion", async ({ page }) => {
+  const searchID = "prt_websearch_mutation"
+  const input = { query: "timeline stability" }
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([toolPart(searchID, "websearch", "completed", input, { output: "https://example.com/one" })]),
+    ],
+  })
+  const wrapper = page.locator(`[data-timeline-part-id="${searchID}"]`)
+  const trigger = wrapper.locator('[data-slot="collapsible-trigger"]')
+  await trigger.click()
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  await timeline.send(
+    partUpdated(
+      toolPart(searchID, "websearch", "completed", input, {
+        output: "https://example.com/one\nhttps://example.com/two",
+      }),
+    ),
+    300,
+  )
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  await expect(wrapper.locator('a[href="https://example.com/two"]')).toBeVisible()
+})
+
+test("preserves an expanded tool error card across duplicate delivery", async ({ page }) => {
+  const toolID = "prt_duplicate_error"
+  const failed = toolPart(toolID, "bash", "error", { command: "exit 1" }, { error: "Command failed visibly" })
+  const timeline = await setupTimeline(page, { messages: [userMessage(), assistantMessage([failed])] })
+  const wrapper = page.locator(`[data-timeline-part-id="${toolID}"]`)
+  const trigger = wrapper.locator('[data-slot="collapsible-trigger"]')
+  await trigger.click()
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  await timeline.send(partUpdated(failed), 150)
+  await timeline.send(partUpdated(failed), 250)
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  await expect(wrapper).toContainText("Command failed visibly")
+})
+
+test("renders multiple question answers and preserves open state on answer updates", async ({ page }) => {
+  const questionID = "prt_multi_question"
+  const input = {
+    questions: [
+      { header: "First", question: "First choice?", options: [] },
+      { header: "Second", question: "Second choice?", options: [], multiple: true },
+    ],
+  }
+  const timeline = await setupTimeline(page, {
+    messages: [
+      userMessage(),
+      assistantMessage([
+        toolPart(questionID, "question", "completed", input, { metadata: { answers: [["A"], ["B", "C"]] } }),
+      ]),
+    ],
+  })
+  const wrapper = page.locator(`[data-timeline-part-id="${questionID}"]`)
+  const trigger = wrapper.locator('[data-slot="collapsible-trigger"]')
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  await timeline.send(
+    partUpdated(
+      toolPart(questionID, "question", "completed", input, { metadata: { answers: [["Updated"], ["B", "C"]] } }),
+    ),
+    300,
+  )
+  await expect(trigger).toHaveAttribute("aria-expanded", "true")
+  await expect(wrapper).toContainText("Updated")
+  await expect(wrapper).toContainText("B, C")
+})
@@ -0,0 +1,116 @@
+import { expect, test } from "@playwright/test"
+import {
+  assistantMessage,
+  partUpdated,
+  setupTimeline,
+  status,
+  textPart,
+  userMessage,
+} from "../performance/timeline-stability/fixture"
+
+test("keeps one connection open while delivering multiple events", async ({ page }) => {
+  const timeline = await setupTimeline(page)
+
+  const first = await timeline.transport.send(partUpdated(textPart("prt_transport_first", "first event")))
+  const second = await timeline.transport.send(partUpdated(textPart("prt_transport_second", "second event")))
+
+  await timeline.waitForPart("prt_transport_first")
+  await timeline.waitForPart("prt_transport_second")
+  expect(first.connectionID).toBe(second.connectionID)
+  expect(await timeline.transport.connections()).toHaveLength(1)
+  expect(await timeline.transport.acknowledgements()).toHaveLength(2)
+})
+
+test("delivers a burst from one stream chunk", async ({ page }) => {
+  const timeline = await setupTimeline(page)
+  const acknowledgements = await timeline.transport.burst([
+    partUpdated(textPart("prt_transport_burst_a", "burst a")),
+    partUpdated(textPart("prt_transport_burst_b", "burst b")),
+  ])
+
+  await timeline.waitForPart("prt_transport_burst_a")
+  await timeline.waitForPart("prt_transport_burst_b")
+  expect(acknowledgements.map((item) => item.chunkCount)).toEqual([1, 1])
+  expect(new Set(acknowledgements.map((item) => item.deliveryID)).size).toBe(2)
+})
+
+test("parses split JSON and a split multibyte code point", async ({ page }) => {
+  const timeline = await setupTimeline(page)
+  const payload = partUpdated(textPart("prt_transport_split", "split snowman \u2603\u2603\u2603"))
+  const encoded = new TextEncoder().encode(`data: ${JSON.stringify(payload)}\n\n`)
+  const snowman = new TextEncoder().encode("\u2603")[0]!
+  const multibyte = encoded.indexOf(snowman)
+
+  const acknowledgement = await timeline.transport.split(payload, [9, multibyte + 1, multibyte + 2])
+
+  await timeline.waitForPart("prt_transport_split")
+  await expect(page.locator('[data-timeline-part-id="prt_transport_split"]')).toContainText(
+    "split snowman \u2603\u2603\u2603",
+  )
+  expect(acknowledgement.chunkCount).toBe(4)
+})
+
+test("delivers server heartbeat without mutating the timeline", async ({ page }) => {
+  const timeline = await setupTimeline(page, {
+    messages: [userMessage(), assistantMessage([textPart("prt_transport_steady", "steady")])],
+  })
+  const before = await page.locator("[data-timeline-row]").allTextContents()
+
+  await timeline.transport.heartbeat()
+  await timeline.settle()
+
+  expect(await page.locator("[data-timeline-row]").allTextContents()).toEqual(before)
+  expect(await timeline.transport.connections()).toHaveLength(1)
+})
+
+test("reconnects after a clean close", async ({ page }) => {
+  const timeline = await setupTimeline(page, { eventRetry: 10 })
+  const first = await timeline.transport.waitForConnection()
+
+  await timeline.transport.close()
+  const second = await timeline.transport.waitForConnection({ after: first.id })
+  await timeline.transport.send(partUpdated(textPart("prt_transport_close", "after close")))
+
+  await timeline.waitForPart("prt_transport_close")
+  expect(second.id).toBeGreaterThan(first.id)
+  expect((await timeline.transport.connections())[0]?.endedBy).toBe("close")
+})
+
+test("reconnects after a stream error", async ({ page }) => {
+  const timeline = await setupTimeline(page, { eventRetry: 10 })
+  const first = await timeline.transport.waitForConnection()
+
+  await timeline.transport.error("contract failure")
+  const second = await timeline.transport.waitForConnection({ after: first.id })
+  await timeline.transport.send(status("busy"))
+
+  await expect.poll(async () => (await timeline.transport.connections()).length).toBe(2)
+  expect(second.id).toBeGreaterThan(first.id)
+  expect((await timeline.transport.connections())[0]?.endedBy).toBe("error")
+})
+
+test("records event IDs and reconnect Last-Event-ID headers", async ({ page }) => {
+  const timeline = await setupTimeline(page, { eventRetry: 10 })
+  const first = await timeline.transport.send(partUpdated(textPart("prt_transport_id", "event with id")), {
+    id: "timeline-event-7",
+  })
+  await timeline.waitForPart("prt_transport_id")
+
+  await timeline.transport.error("retry with event id")
+  const connection = await timeline.transport.waitForConnection({ after: first.connectionID })
+
+  expect(first.eventID).toBe("timeline-event-7")
+  expect(connection.headers["last-event-id"]).toBe("timeline-event-7")
+})
+
+test("passes through non-event fetches", async ({ page }) => {
+  const timeline = await setupTimeline(page)
+
+  const health = await page.evaluate(async () => {
+    const response = await fetch("/global/health")
+    return response.json()
+  })
+
+  expect(health).toEqual({ healthy: true })
+  expect(await timeline.transport.connections()).toHaveLength(1)
+})
@@ -145,7 +145,7 @@ async function configurePage(page: Page) {
        }),
      )
      localStorage.setItem(
-        "opencode.global.dat:tabs",
+        "opencode.window.browser.dat:tabs",
        JSON.stringify(sessionIDs.map((sessionId) => ({ type: "session", server, dirBase64, sessionId }))),
      )
    },
@@ -0,0 +1,200 @@
+import { base64Encode } from "@opencode-ai/core/util/encode"
+import { expect, test, type Page } from "@playwright/test"
+import { mockOpenCodeServer } from "../utils/mock-server"
+import { expectSessionTitle } from "../utils/waits"
+
+const directory = "C:/OpenCode/SubagentNavigation"
+const projectID = "proj_subagent_navigation"
+const parentID = "ses_subagent_parent"
+const childID = "ses_subagent_child"
+const parentTitle = "Parent session"
+const childTitle = "Subagent child session"
+// Child session pages derive their heading from the task part that spawned them.
+const taskDescription = "Inspect child navigation"
+
+type EventPayload = { directory: string; payload: Record<string, unknown> }
+
+test.use({ viewport: { width: 1440, height: 900 } })
+
+test("navigates to a subagent child session missing from the session list", async ({ page }) => {
+  await setup(page)
+  await openChildFromParent(page)
+
+  await expectSessionTitle(page, taskDescription)
+  await expect(page.getByRole("heading", { name: parentTitle })).toHaveCount(0)
+
+  const titlebarRight = page.locator("#opencode-titlebar-right")
+  await expect(titlebarRight.getByRole("button", { name: "Toggle review" })).toHaveCount(1)
+})
+
+test("shows the not found fallback when the viewed session is deleted", async ({ page }) => {
+  const events: EventPayload[] = []
+  await setup(page, () => events.splice(0, 1))
+  await openChildFromParent(page)
+  await expectSessionTitle(page, taskDescription)
+
+  events.push({
+    directory,
+    payload: { type: "session.deleted", properties: { info: childSession() } },
+  })
+
+  await expect(page.getByText("This session cannot be found")).toBeVisible()
+  await expect(page.getByRole("button", { name: "Close Tab" })).toBeVisible()
+  await expect(page.getByRole("heading", { name: taskDescription })).toHaveCount(0)
+})
+
+async function setup(page: Page, events?: () => EventPayload[]) {
+  await mockOpenCodeServer(page, {
+    directory,
+    project: {
+      id: projectID,
+      worktree: directory,
+      vcs: "git",
+      name: "subagent-navigation",
+      time: { created: 1700000000000, updated: 1700000000000 },
+      sandboxes: [],
+    },
+    provider: {
+      all: [
+        {
+          id: "opencode",
+          name: "OpenCode",
+          models: {
+            "claude-opus-4-6": { id: "claude-opus-4-6", name: "Claude Opus 4.6", limit: { context: 200_000 } },
+          },
+        },
+      ],
+      connected: ["opencode"],
+      default: { providerID: "opencode", modelID: "claude-opus-4-6" },
+    },
+    sessions: [session(parentID, parentTitle, 1700000000000), childSession()],
+    pageMessages: (sessionID) => ({ items: sessionID === parentID ? parentMessages() : [] }),
+    events,
+    eventRetry: events ? 16 : undefined,
+  })
+  // The child session resolves via /session/:id but is absent from the /session list,
+  // matching a subagent session that has not been loaded into the list cache yet.
+  await page.route(
+    (url) => url.pathname === "/session" && url.port === (process.env.PLAYWRIGHT_SERVER_PORT ?? "4096"),
+    (route) =>
+      route.fulfill({
+        status: 200,
+        contentType: "application/json",
+        headers: { "access-control-allow-origin": "*" },
+        body: JSON.stringify([session(parentID, parentTitle, 1700000000000)]),
+      }),
+  )
+  await configurePage(page)
+}
+
+async function openChildFromParent(page: Page) {
+  await page.goto(sessionHref(parentID))
+  await expectSessionTitle(page, parentTitle)
+
+  const card = page.locator(`a[href="${sessionHref(childID)}"]`)
+  await expect(card).toBeVisible()
+  await card.click()
+
+  await expect(page).toHaveURL(new RegExp(`/server/.+/session/${childID}$`), { timeout: 15_000 })
+}
+
+function session(id: string, title: string, created: number, extra?: Record<string, unknown>) {
+  return {
+    id,
+    slug: id,
+    projectID,
+    directory,
+    title,
+    version: "dev",
+    time: { created, updated: created },
+    ...extra,
+  }
+}
+
+function childSession() {
+  return session(childID, childTitle, 1700000001000, { parentID })
+}
+
+function parentMessages() {
+  const userID = "msg_user_0001"
+  const assistantID = "msg_assistant_0001"
+  return [
+    {
+      info: {
+        id: userID,
+        sessionID: parentID,
+        role: "user",
+        time: { created: 1700000000000 },
+        agent: "build",
+        model: { providerID: "opencode", modelID: "claude-opus-4-6" },
+      },
+      parts: [
+        {
+          id: "prt_user_text_0001",
+          sessionID: parentID,
+          messageID: userID,
+          type: "text",
+          text: "Delegate work to a subagent",
+        },
+      ],
+    },
+    {
+      info: {
+        id: assistantID,
+        sessionID: parentID,
+        role: "assistant",
+        time: { created: 1700000001000, completed: 1700000002000 },
+        parentID: userID,
+        modelID: "claude-opus-4-6",
+        providerID: "opencode",
+        mode: "build",
+        agent: "build",
+        path: { cwd: directory, root: directory },
+        cost: 0.01,
+        tokens: { input: 100, output: 200, reasoning: 0, cache: { read: 0, write: 0 } },
+        finish: "stop",
+      },
+      parts: [
+        {
+          id: "prt_tool_task_0001",
+          sessionID: parentID,
+          messageID: assistantID,
+          type: "tool",
+          callID: "call_task_0001",
+          tool: "task",
+          state: {
+            status: "completed",
+            input: { description: taskDescription, subagent_type: "explore" },
+            output: "Subagent finished",
+            title: taskDescription,
+            metadata: { sessionId: childID },
+            time: { start: 1700000001000, end: 1700000002000 },
+          },
+        },
+      ],
+    },
+  ]
+}
+
+async function configurePage(page: Page) {
+  const server = `http://${process.env.PLAYWRIGHT_SERVER_HOST ?? "127.0.0.1"}:${process.env.PLAYWRIGHT_SERVER_PORT ?? "4096"}`
+  await page.addInitScript(
+    ({ directory, server, sessionId }) => {
+      localStorage.setItem("settings.v3", JSON.stringify({ general: { newLayoutDesigns: true } }))
+      localStorage.setItem(
+        "opencode.global.dat:server",
+        JSON.stringify({
+          projects: { local: [{ worktree: directory, expanded: true }] },
+          lastProject: { local: directory },
+        }),
+      )
+      localStorage.setItem("opencode.window.browser.dat:tabs", JSON.stringify([{ type: "session", server, sessionId }]))
+    },
+    { directory, server, sessionId: parentID },
+  )
+}
+
+function sessionHref(sessionID: string) {
+  const server = `http://${process.env.PLAYWRIGHT_SERVER_HOST ?? "127.0.0.1"}:${process.env.PLAYWRIGHT_SERVER_PORT ?? "4096"}`
+  return `/server/${base64Encode(server)}/session/${sessionID}`
+}
@@ -127,7 +127,7 @@ test.describe("smoke: session timeline", () => {
    await page.addInitScript(
      ({ dirBase64, sourceID, targetID }) => {
        localStorage.setItem(
-          "opencode.global.dat:tabs",
+          "opencode.window.browser.dat:tabs",
          JSON.stringify(
            [sourceID, targetID].map((sessionId) => ({
              type: "session",
@@ -253,7 +253,7 @@ test.describe("smoke: session timeline", () => {
    await page.addInitScript(
      ({ dirBase64, sourceID, targetID }) => {
        localStorage.setItem(
-          "opencode.global.dat:tabs",
+          "opencode.window.browser.dat:tabs",
          JSON.stringify(
            [sourceID, targetID].map((sessionId) => ({
              type: "session",
@@ -5,5 +5,12 @@
    "rootDir": "..",
    "types": ["node", "bun"]
  },
-  "include": ["./**/*.ts"]
+  "include": [
+    "./performance/timeline-stability/**/*.spec.ts",
+    "./performance/timeline-stability/fixture.test.ts",
+    "./performance/timeline-stability/fixture.ts",
+    "./performance/unit/visual-stability.test.ts",
+    "./regression/session-timeline-context-resize.spec.ts",
+    "./utils/**/*.ts"
+  ]
 }
@@ -1,7 +1,7 @@
 import type { Page, Route } from "@playwright/test"

 const emptyList = new Set(["/skill", "/command", "/lsp", "/formatter", "/vcs/status", "/vcs/diff"])
-const emptyObject = new Set(["/global/config", "/config", "/provider/auth", "/mcp", "/session/status"])
+const emptyObject = new Set(["/global/config", "/config", "/provider/auth", "/mcp"])

 export interface MockServerConfig {
  provider: unknown
@@ -17,6 +17,7 @@ export interface MockServerConfig {
  todos?: (sessionID: string) => unknown[]
  permissions?: unknown[] | (() => unknown[])
  questions?: unknown[] | (() => unknown[])
+  sessionStatus?: unknown
 }

 export async function mockOpenCodeServer(page: Page, config: MockServerConfig) {
@@ -53,6 +54,7 @@ export async function mockOpenCodeServer(page: Page, config: MockServerConfig) {
      return json(route, typeof config.permissions === "function" ? config.permissions() : (config.permissions ?? []))
    if (path === "/question")
      return json(route, typeof config.questions === "function" ? config.questions() : (config.questions ?? []))
+    if (path === "/session/status") return json(route, config.sessionStatus ?? {})
    if (path === "/vcs/diff" && config.vcsDiff) return json(route, config.vcsDiff)
    if (emptyObject.has(path)) return json(route, {})
    if (emptyList.has(path)) return json(route, [])
@@ -0,0 +1,284 @@
+import type { Page } from "@playwright/test"
+
+export type SseConnectionRecord = {
+  id: number
+  url: string
+  path: "/global/event" | "/event"
+  headers: Record<string, string>
+  openedAt: number
+  endedAt?: number
+  endedBy?: "close" | "disconnect" | "error" | "abort"
+  error?: string
+}
+
+export type SseDeliveryAcknowledgement = {
+  deliveryID: number
+  connectionID: number
+  bytes: number
+  chunkCount: number
+  deliveredAt: number
+  eventID?: string
+}
+
+export type SseEventOptions = {
+  id?: string
+  event?: string
+  retry?: number
+  marker?: string
+}
+
+export type SseTransport<T> = {
+  server: string
+  waitForConnection(options?: { after?: number; timeout?: number }): Promise<SseConnectionRecord>
+  send(payload: T, options?: SseEventOptions): Promise<SseDeliveryAcknowledgement>
+  burst(payloads: readonly T[], options?: readonly SseEventOptions[]): Promise<SseDeliveryAcknowledgement[]>
+  split(payload: T, cuts: readonly number[], options?: SseEventOptions): Promise<SseDeliveryAcknowledgement>
+  heartbeat(options?: SseEventOptions): Promise<SseDeliveryAcknowledgement>
+  writeRaw(value: string | Uint8Array, cuts?: readonly number[], marker?: string): Promise<SseDeliveryAcknowledgement>
+  close(): Promise<void>
+  disconnect(message?: string): Promise<void>
+  error(message?: string): Promise<void>
+  connections(): Promise<SseConnectionRecord[]>
+  acknowledgements(): Promise<SseDeliveryAcknowledgement[]>
+}
+
+type BrowserCommand<T> =
+  | { type: "send"; deliveries: { payload: T; options?: SseEventOptions }[]; burst: boolean; cuts?: number[] }
+  | { type: "raw"; bytes: number[]; cuts?: number[]; marker?: string }
+  | { type: "end"; mode: "close" | "disconnect" | "error"; message?: string }
+  | { type: "connections" }
+  | { type: "acknowledgements" }
+
+type BrowserTransport = Window & {
+  __testSseTransport?: {
+    command: (command: BrowserCommand<unknown>) => unknown
+  }
+}
+
+export async function installSseTransport<T>(
+  page: Page,
+  options: { server: string; retry?: number },
+): Promise<SseTransport<T>> {
+  const server = new URL(options.server).origin
+  await page.addInitScript(
+    ({ server, retry }) => {
+      type Connection = SseConnectionRecord & { controller: ReadableStreamDefaultController<Uint8Array> }
+      type ProbeWindow = Window & {
+        __visualStabilityProbe?: { startedAt: number; markers: { at: number; label: string }[] }
+      }
+      const originalFetch = window.fetch.bind(window)
+      const connections: Connection[] = []
+      const acknowledgements: SseDeliveryAcknowledgement[] = []
+      const encoder = new TextEncoder()
+      let nextConnectionID = 0
+      let nextDeliveryID = 0
+
+      const current = () => connections.findLast((connection) => connection.endedAt === undefined)
+      const chunks = (bytes: Uint8Array, cuts?: readonly number[]) => {
+        const boundaries = [...new Set(cuts ?? [])]
+          .filter((cut) => Number.isInteger(cut) && cut > 0 && cut < bytes.byteLength)
+          .sort((a, b) => a - b)
+        return [0, ...boundaries].map((start, index) => bytes.slice(start, boundaries[index] ?? bytes.byteLength))
+      }
+      const marker = (label?: string) => {
+        if (!label) return
+        const probe = (window as ProbeWindow).__visualStabilityProbe
+        if (!probe) return
+        probe.markers.push({ at: performance.now() - probe.startedAt, label })
+      }
+      const frame = (payload: unknown, eventOptions: SseEventOptions = {}) =>
+        [
+          eventOptions.event === undefined ? "" : `event: ${eventOptions.event}\n`,
+          eventOptions.id === undefined ? "" : `id: ${eventOptions.id}\n`,
+          eventOptions.retry === undefined ? "" : `retry: ${eventOptions.retry}\n`,
+          `data: ${JSON.stringify(payload)}\n\n`,
+        ].join("")
+      const acknowledge = (
+        connection: Connection,
+        bytes: number,
+        chunkCount: number,
+        eventID?: string,
+      ): SseDeliveryAcknowledgement => {
+        const acknowledgement = {
+          deliveryID: ++nextDeliveryID,
+          connectionID: connection.id,
+          bytes,
+          chunkCount,
+          deliveredAt: performance.now(),
+          ...(eventID === undefined ? {} : { eventID }),
+        }
+        acknowledgements.push(acknowledgement)
+        return acknowledgement
+      }
+      const end = (mode: "close" | "disconnect" | "error", message?: string) => {
+        const connection = current()
+        if (!connection) throw new Error("SSE transport has no active connection")
+        connection.endedAt = performance.now()
+        connection.endedBy = mode
+        if (message) connection.error = message
+        if (mode === "close") {
+          connection.controller.close()
+          return
+        }
+        const error = new DOMException(
+          message ?? "SSE connection disconnected",
+          mode === "error" ? "Error" : "NetworkError",
+        )
+        connection.controller.error(error)
+      }
+
+      const command = (input: BrowserCommand<unknown>) => {
+        if (input.type === "connections")
+          return connections.map(({ controller: _controller, ...connection }) => connection)
+        if (input.type === "acknowledgements") return acknowledgements
+        if (input.type === "end") return end(input.mode, input.message)
+        const connection = current()
+        if (!connection) throw new Error("SSE transport has no active connection")
+        if (input.type === "raw") {
+          marker(input.marker)
+          const output = chunks(new Uint8Array(input.bytes), input.cuts)
+          output.forEach((chunk) => connection.controller.enqueue(chunk))
+          return acknowledge(connection, input.bytes.length, output.length)
+        }
+        const encoded = input.deliveries.map((delivery) => ({
+          delivery,
+          bytes: encoder.encode(frame(delivery.payload, delivery.options)),
+        }))
+        encoded.forEach((item) => marker(item.delivery.options?.marker))
+        if (input.burst) {
+          const bytes = encoder.encode(
+            encoded.map((item) => frame(item.delivery.payload, item.delivery.options)).join(""),
+          )
+          connection.controller.enqueue(bytes)
+          return encoded.map((item) => acknowledge(connection, item.bytes.byteLength, 1, item.delivery.options?.id))
+        }
+        const output = chunks(encoded[0]!.bytes, input.cuts)
+        output.forEach((chunk) => connection.controller.enqueue(chunk))
+        return acknowledge(connection, encoded[0]!.bytes.byteLength, output.length, encoded[0]!.delivery.options?.id)
+      }
+
+      ;(window as BrowserTransport).__testSseTransport = { command }
+      const fetch = (input: RequestInfo | URL, init?: RequestInit) => {
+        const request = new Request(input, init)
+        const url = new URL(request.url)
+        if (url.origin !== server || (url.pathname !== "/global/event" && url.pathname !== "/event"))
+          return originalFetch(input, init)
+
+        const id = ++nextConnectionID
+        const record = {
+          id,
+          url: url.href,
+          path: url.pathname,
+          headers: Object.fromEntries(request.headers.entries()),
+          openedAt: performance.now(),
+        } as Connection
+        const stream = new ReadableStream<Uint8Array>({
+          start(controller) {
+            record.controller = controller
+            connections.push(record)
+            if (retry !== undefined) controller.enqueue(encoder.encode(`retry: ${retry}\n\n`))
+            request.signal.addEventListener(
+              "abort",
+              () => {
+                if (record.endedAt !== undefined) return
+                record.endedAt = performance.now()
+                record.endedBy = "abort"
+                controller.error(request.signal.reason ?? new DOMException("The operation was aborted", "AbortError"))
+              },
+              { once: true },
+            )
+          },
+          cancel() {
+            if (record.endedAt !== undefined) return
+            record.endedAt = performance.now()
+            record.endedBy = "disconnect"
+          },
+        })
+        return Promise.resolve(
+          new Response(stream, {
+            status: 200,
+            headers: {
+              "cache-control": "no-cache",
+              "content-type": "text/event-stream",
+            },
+          }),
+        )
+      }
+      Object.defineProperty(window, "fetch", { configurable: true, writable: true, value: fetch })
+    },
+    { server, retry: options.retry },
+  )
+
+  const command = <Result>(input: BrowserCommand<T>) =>
+    page.evaluate((input) => {
+      const transport = (window as BrowserTransport).__testSseTransport
+      if (!transport) throw new Error("SSE transport was not installed before page load")
+      return transport.command(input as BrowserCommand<unknown>)
+    }, input) as Promise<Result>
+
+  return {
+    server,
+    async waitForConnection(input = {}) {
+      await page.waitForFunction(
+        (after) => {
+          const transport = (window as BrowserTransport).__testSseTransport
+          const connections = transport?.command({ type: "connections" }) as SseConnectionRecord[] | undefined
+          return connections?.some((connection) => connection.id > after)
+        },
+        input.after ?? 0,
+        { timeout: input.timeout },
+      )
+      return (await command<SseConnectionRecord[]>({ type: "connections" })).findLast(
+        (connection) => connection.id > (input.after ?? 0),
+      )!
+    },
+    send(payload, eventOptions) {
+      return command({ type: "send", deliveries: [{ payload, options: eventOptions }], burst: false })
+    },
+    burst(payloads, eventOptions = []) {
+      return command({
+        type: "send",
+        deliveries: payloads.map((payload, index) => ({ payload, options: eventOptions[index] })),
+        burst: true,
+      })
+    },
+    split(payload, cuts, eventOptions) {
+      return command({ type: "send", deliveries: [{ payload, options: eventOptions }], burst: false, cuts: [...cuts] })
+    },
+    heartbeat(eventOptions) {
+      return command({
+        type: "send",
+        deliveries: [
+          {
+            payload: { directory: "global", payload: { type: "server.heartbeat", properties: {} } } as T,
+            options: eventOptions,
+          },
+        ],
+        burst: false,
+      })
+    },
+    writeRaw(value, cuts, marker) {
+      return command({
+        type: "raw",
+        bytes: Array.from(typeof value === "string" ? new TextEncoder().encode(value) : value),
+        cuts: cuts ? [...cuts] : undefined,
+        marker,
+      })
+    },
+    close() {
+      return command({ type: "end", mode: "close" })
+    },
+    disconnect(message) {
+      return command({ type: "end", mode: "disconnect", message })
+    },
+    error(message) {
+      return command({ type: "end", mode: "error", message })
+    },
+    connections() {
+      return command({ type: "connections" })
+    },
+    acknowledgements() {
+      return command({ type: "acknowledgements" })
+    },
+  }
+}
@@ -0,0 +1,54 @@
+import type { Page, TestInfo } from "@playwright/test"
+import { analyzeVisualObservations, analyzeVisualTraceByMarker } from "./visual-stability/analyzer"
+import { legacyVisualPlan, type LegacyVisualStabilityOptions } from "./visual-stability/invariant"
+import type { CapturedFrame, VisualStabilityTrace } from "./visual-stability/model"
+import { markVisualProbe, startVisualProbe, stopVisualProbe } from "./visual-stability/probe"
+import type { VisualRegionDefinition } from "./visual-stability/regions"
+import { reportVisualStability } from "./visual-stability/reporter"
+
+export * from "./visual-stability/index"
+
+const capturedFrames = Symbol("capturedFrames")
+
+export async function startVisualStabilityProbe(page: Page, regions: Record<string, VisualRegionDefinition>) {
+  await startVisualProbe(page, regions)
+}
+
+export async function stopVisualStabilityProbe(page: Page) {
+  const result = await stopVisualProbe(page)
+  const trace: VisualStabilityTrace = { markers: result.markers, samples: result.samples }
+  Object.defineProperty(trace, capturedFrames, { value: result.frames })
+  return trace
+}
+
+export async function markVisualStability(page: Page, label: string) {
+  await markVisualProbe(page, label)
+}
+
+export function analyzeVisualStability(trace: VisualStabilityTrace, options: LegacyVisualStabilityOptions = {}) {
+  return analyzeVisualObservations(trace.samples, legacyVisualPlan(options))
+}
+
+export function analyzeVisualStabilityByMarker(
+  trace: VisualStabilityTrace,
+  options: LegacyVisualStabilityOptions = {},
+) {
+  return analyzeVisualTraceByMarker(trace, legacyVisualPlan(options))
+}
+
+export async function expectVisualStability(
+  testInfo: TestInfo,
+  name: string,
+  trace: VisualStabilityTrace,
+  options: LegacyVisualStabilityOptions = {},
+) {
+  await reportVisualStability(
+    testInfo,
+    name,
+    {
+      ...trace,
+      frames: (trace as VisualStabilityTrace & { [capturedFrames]?: CapturedFrame[] })[capturedFrames] ?? [],
+    },
+    legacyVisualPlan(options),
+  )
+}
@@ -0,0 +1,209 @@
+import type { VisualInvariant, VisualPlan } from "./invariant"
+import type { VisualObservation, VisualStabilityTrace } from "./model"
+
+export function analyzeVisualObservations<RegionName extends string>(
+  observations: readonly VisualObservation<RegionName>[],
+  plan: VisualPlan<RegionName>,
+) {
+  const issues: string[] = []
+  const invariants = plan.invariants
+  const names = [...new Set(observations.flatMap((sample) => Object.keys(sample.regions) as RegionName[]))]
+  const required = regions(invariants, "required")
+  const continuousAny = invariants.filter(
+    (invariant): invariant is Extract<VisualInvariant<RegionName>, { type: "continuous-any" }> =>
+      invariant.type === "continuous-any",
+  )
+  const unique = new Set(regions(invariants, "unique"))
+  const stable = new Set(regions(invariants, "stable"))
+  const fixed = invariants.filter(
+    (invariant): invariant is Extract<VisualInvariant<RegionName>, { type: "fixed" }> => invariant.type === "fixed",
+  )
+  const opacity = invariants.filter(
+    (invariant): invariant is Extract<VisualInvariant<RegionName>, { type: "opacity" }> => invariant.type === "opacity",
+  )
+  const continuity = invariants.filter(
+    (invariant): invariant is Extract<VisualInvariant<RegionName>, { type: "continuity" }> =>
+      invariant.type === "continuity",
+  )
+  const motion = invariants.filter(
+    (invariant): invariant is Extract<VisualInvariant<RegionName>, { type: "motion" }> => invariant.type === "motion",
+  )
+  const labelStability = invariants.filter(
+    (invariant): invariant is Extract<VisualInvariant<RegionName>, { type: "label-stability" }> =>
+      invariant.type === "label-stability",
+  )
+
+  for (const name of new Set(required)) {
+    if (!observations.some((sample) => sample.regions[name]?.visible)) issues.push(`${name} never rendered`)
+  }
+  for (const invariant of continuousAny) {
+    if (!invariant.regions.some((name) => observations.some((sample) => sample.regions[name]?.visible)))
+      issues.push(`${invariant.regions.join(" | ")} never rendered`)
+  }
+
+  for (const name of names) {
+    const samples = observations.flatMap((observation) => {
+      const region = observation.regions[name]
+      if (!region) return []
+      const clipped =
+        observation.viewport && (region.bottom <= observation.viewport.top || region.top >= observation.viewport.bottom)
+      return [{ at: observation.at, ...region, visible: region.visible && !clipped }]
+    })
+    const visible = samples.filter((sample) => sample.visible)
+    if (visible.length === 0) continue
+    if (unique.has(name)) {
+      const duplicate = samples.find((sample) => sample.count > 1)
+      if (duplicate) issues.push(`${name} appeared ${duplicate.count} times at ${Math.round(duplicate.at)}ms`)
+    }
+    if (stable.has(name)) {
+      const identities = [...new Set(visible.map((sample) => sample.node).filter((node) => node > 0))]
+      if (identities.length > 1) issues.push(`${name} remounted ${identities.length - 1} times`)
+    }
+    for (const invariant of fixed.filter((invariant) => includes(invariant.regions, name))) {
+      const origin = visible[0]
+      const movement = origin ? Math.max(0, ...visible.map((sample) => Math.abs(sample.top - origin.top))) : 0
+      if (movement > (invariant.tolerance ?? 1))
+        issues.push(`${name} moved ${Math.round(movement * 10) / 10}px in the viewport`)
+    }
+    for (const invariant of opacity.filter((invariant) => includes(invariant.regions, name))) {
+      for (const sample of visible) {
+        if (sample.opacity < (invariant.floor ?? 0.65))
+          issues.push(`${name} opacity fell to ${sample.opacity} at ${Math.round(sample.at)}ms`)
+      }
+    }
+    if (continuity.some((invariant) => includes(invariant.regions, name))) {
+      const firstPresent = samples.findIndex((sample) => sample.present)
+      const lastPresent = samples.findLastIndex((sample) => sample.present)
+      if (samples.slice(firstPresent, lastPresent + 1).some((sample) => !sample.present))
+        issues.push(`${name} disappeared between present frames`)
+      const firstVisible = samples.findIndex((sample) => sample.visible)
+      const lastVisible = samples.findLastIndex((sample) => sample.visible)
+      if (
+        firstVisible >= 0 &&
+        samples.slice(firstVisible, lastVisible + 1).some((sample) => !sample.visible && sample.inViewport)
+      )
+        issues.push(`${name} blanked between visible frames`)
+    }
+    for (const invariant of motion.filter((invariant) => includes(invariant.regions, name))) {
+      for (const metric of ["top", "bottom", "width", "height"] as const) {
+        const directions = visible
+          .slice(1)
+          .map((sample, index) => sample[metric] - visible[index]![metric])
+          .filter((delta) => Math.abs(delta) > (invariant.tolerance ?? 1))
+          .map(Math.sign)
+        const reversals = directions.slice(1).filter((direction, index) => direction !== directions[index]).length
+        const allowed =
+          metric === "top" || metric === "bottom"
+            ? (invariant.maxPositionReversals ?? invariant.maxReversals ?? 1)
+            : (invariant.maxReversals ?? 1)
+        if (reversals > allowed) issues.push(`${name} ${metric} reversed ${reversals} times`)
+      }
+    }
+    if (labelStability.some((invariant) => includes(invariant.regions, name))) {
+      const labels = samples
+        .map((sample) => sample.label)
+        .filter((label) => label.length > 0)
+        .filter((label, index, all) => label !== all[index - 1])
+      if (labels.some((label, index) => labels.indexOf(label) !== index))
+        issues.push(`${name} label reverted: ${labels.join(" -> ")}`)
+    }
+  }
+
+  if (invariants.some((invariant) => invariant.type === "preserve-bottom-anchor")) {
+    const viewports = observations.flatMap((sample) => (sample.viewport ? [sample.viewport] : []))
+    if (viewports[0] && viewports[0].distanceFromBottom <= 4) {
+      const lost = viewports.find((viewport) => viewport.distanceFromBottom > 4)
+      if (lost) issues.push(`bottom anchor moved to ${lost.distanceFromBottom}px`)
+    }
+  }
+  if (invariants.some((invariant) => invariant.type === "acquire-bottom-anchor")) {
+    const final = observations.findLast((sample) => sample.viewport)?.viewport
+    if (!final || final.distanceFromBottom > 4)
+      issues.push(`did not acquire bottom anchor${final ? ` (${final.distanceFromBottom}px away)` : ""}`)
+  }
+
+  for (const invariant of continuousAny) {
+    const active = observations.map((sample) => invariant.regions.some((name) => sample.regions[name]?.visible))
+    const first = active.indexOf(true)
+    const last = active.lastIndexOf(true)
+    if (first >= 0 && active.slice(first, last + 1).some((value) => !value))
+      issues.push(`${invariant.regions.join(" | ")} blanked between visible frames`)
+  }
+
+  for (const invariant of invariants.filter(
+    (item): item is Extract<VisualInvariant<RegionName>, { type: "flow" }> => item.type === "flow",
+  )) {
+    for (const [before, after] of invariant.regions
+      .slice(1)
+      .map((after, index) => [invariant.regions[index]!, after])) {
+      let maximum: { overlap: number; at: number } | undefined
+      let inverted: { at: number } | undefined
+      for (const sample of observations) {
+        const first = sample.regions[before]
+        const second = sample.regions[after]
+        if (!first?.visible || !second?.visible) continue
+        if (
+          sample.viewport &&
+          (first.bottom <= sample.viewport.top ||
+            first.top >= sample.viewport.bottom ||
+            second.bottom <= sample.viewport.top ||
+            second.top >= sample.viewport.bottom)
+        )
+          continue
+        const overlap = first.bottom - second.top
+        if (first.top > second.top && !inverted) inverted = { at: sample.at }
+        if (overlap > (invariant.overlapTolerance ?? 0.5) && (!maximum || overlap > maximum.overlap))
+          maximum = { overlap, at: sample.at }
+      }
+      if (inverted) issues.push(`${before} rendered after ${after} at ${Math.round(inverted.at)}ms`)
+      if (maximum)
+        issues.push(
+          `${before} overlapped ${after} by ${Math.round(maximum.overlap * 10) / 10}px at ${Math.round(maximum.at)}ms`,
+        )
+    }
+  }
+  return [...new Set(issues)]
+}
+
+export function analyzeVisualTraceByMarker<RegionName extends string>(
+  trace: VisualStabilityTrace<RegionName>,
+  plan: VisualPlan<RegionName>,
+) {
+  if (trace.markers.length === 0) return analyzeVisualObservations(trace.samples, plan)
+  const required = [...new Set(plan.markerRequired ?? regions(plan.invariants, "required"))].flatMap((name) =>
+    trace.samples.some((sample) => sample.regions[name]?.visible) ? [] : [`${name} never rendered`],
+  )
+  const withoutRequired = plan.invariants.filter((invariant) => invariant.type !== "required")
+  const windows = trace.markers.flatMap((marker, index) => {
+    const end = trace.markers[index + 1]?.at ?? Infinity
+    const before = trace.samples.findLast((sample) => sample.at < marker.at)
+    const samples = [
+      ...(before ? [before] : []),
+      ...trace.samples.filter((sample) => sample.at >= marker.at && sample.at < end),
+    ]
+    if (samples.length < 2) return []
+    return analyzeVisualObservations(samples, { ...plan, perMarker: false, invariants: withoutRequired }).map(
+      (issue) => `${marker.label}: ${issue}`,
+    )
+  })
+  const aggregateMotion =
+    plan.aggregateMotion === false
+      ? []
+      : analyzeVisualObservations(trace.samples, {
+          invariants: plan.invariants.filter((invariant) => invariant.type === "motion"),
+        }).filter((issue) => / (?:top|bottom|width|height) reversed \d+ times$/.test(issue))
+  return [...new Set([...required, ...aggregateMotion, ...windows])]
+}
+
+function regions<RegionName extends string, Type extends VisualInvariant<RegionName>["type"]>(
+  invariants: readonly VisualInvariant<RegionName>[],
+  type: Type,
+) {
+  return invariants.flatMap((invariant) =>
+    invariant.type === type && "regions" in invariant && invariant.regions !== "all" ? [...invariant.regions] : [],
+  ) as RegionName[]
+}
+
+function includes<RegionName extends string>(regions: readonly RegionName[] | "all", name: RegionName) {
+  return regions === "all" || regions.includes(name)
+}
@@ -0,0 +1,51 @@
+import type { CDPSession, Page } from "@playwright/test"
+import type { CapturedFrame } from "./model"
+
+export type VisualCapture = {
+  session: CDPSession
+  frames: CapturedFrame[]
+  startedAtEpoch: number
+  running: boolean
+  capture: Promise<void>
+}
+
+export async function startVisualCapture(page: Page, startedAtEpoch: number) {
+  if (process.env.OPENCODE_STABILITY_CAPTURE !== "1") return
+  const session = await page.context().newCDPSession(page)
+  await session.send("Page.enable")
+  const recording: VisualCapture = {
+    session,
+    frames: [],
+    startedAtEpoch,
+    running: true,
+    capture: Promise.resolve(),
+  }
+  recording.capture = (async () => {
+    try {
+      while (recording.running && recording.frames.length < 900) {
+        const frame = await session.send("Page.captureScreenshot", {
+          format: "jpeg",
+          quality: 80,
+          captureBeyondViewport: false,
+          optimizeForSpeed: true,
+        })
+        recording.frames.push({ at: Date.now() - recording.startedAtEpoch, data: frame.data })
+        await new Promise((resolve) => setTimeout(resolve, 50))
+      }
+    } catch {
+      recording.running = false
+    }
+  })()
+  return recording
+}
+
+export async function stopVisualCapture(recording: VisualCapture | undefined) {
+  if (!recording) return []
+  recording.running = false
+  try {
+    await recording.capture
+  } finally {
+    await recording.session.detach().catch(() => undefined)
+  }
+  return recording.frames
+}
@@ -0,0 +1,8 @@
+export * from "./analyzer"
+export * from "./capture"
+export * from "./invariant"
+export * from "./model"
+export * from "./probe"
+export * from "./regions"
+export * from "./reporter"
+export * from "./scenario"
@@ -0,0 +1,112 @@
+import type { VisualRegionDefinition } from "./regions"
+
+type RegionSet<RegionName extends string> = readonly RegionName[] | "all"
+
+export type VisualInvariant<RegionName extends string = string> =
+  | { type: "required"; regions: readonly RegionName[] }
+  | { type: "continuous-any"; regions: readonly RegionName[] }
+  | { type: "unique"; regions: readonly RegionName[] }
+  | { type: "stable"; regions: readonly RegionName[] }
+  | { type: "fixed"; regions: readonly RegionName[]; tolerance?: number }
+  | { type: "opacity"; regions: RegionSet<RegionName>; floor?: number }
+  | {
+      type: "motion"
+      regions: RegionSet<RegionName>
+      tolerance?: number
+      maxReversals?: number
+      maxPositionReversals?: number
+    }
+  | { type: "continuity"; regions: RegionSet<RegionName> }
+  | { type: "label-stability"; regions: RegionSet<RegionName> }
+  | { type: "flow"; regions: readonly RegionName[]; overlapTolerance?: number }
+  | { type: "preserve-bottom-anchor" }
+  | { type: "acquire-bottom-anchor" }
+
+export type VisualPlan<RegionName extends string = string> = {
+  regionNames?: readonly RegionName[]
+  invariants: readonly VisualInvariant<RegionName>[]
+  markerRequired?: readonly RegionName[]
+  perMarker?: boolean
+  aggregateMotion?: boolean
+}
+
+export type LegacyVisualStabilityOptions<RegionName extends string = string> = {
+  flow?: RegionName[]
+  motionTolerance?: number
+  opacityFloor?: number
+  overlapTolerance?: number
+  maxReversals?: number
+  maxPositionReversals?: number
+  stable?: RegionName[]
+  fixed?: RegionName[]
+  motion?: RegionName[]
+  unique?: RegionName[]
+  preserveBottomAnchor?: boolean
+  acquireBottomAnchor?: boolean
+  perMarker?: boolean
+  continuousAny?: RegionName[][]
+  required?: RegionName[]
+  aggregateMotion?: boolean
+  inferRequired?: boolean
+}
+
+export function visualPlan<const Regions extends Record<string, VisualRegionDefinition>>(
+  regions: Regions,
+  invariants: readonly VisualInvariant<Extract<keyof Regions, string>>[],
+  options: Omit<VisualPlan<Extract<keyof Regions, string>>, "regionNames" | "invariants"> = {},
+): VisualPlan<Extract<keyof Regions, string>> {
+  return { ...options, regionNames: Object.keys(regions) as Extract<keyof Regions, string>[], invariants }
+}
+
+export function legacyVisualPlan<RegionName extends string>(
+  options: LegacyVisualStabilityOptions<RegionName> = {},
+): VisualPlan<RegionName> {
+  const inferred =
+    options.inferRequired === false
+      ? []
+      : [
+          ...(options.stable ?? []),
+          ...(options.fixed ?? []),
+          ...(options.unique ?? []),
+          ...(options.motion ?? []),
+          ...(options.flow ?? []),
+        ]
+  return {
+    perMarker: options.perMarker,
+    aggregateMotion: options.aggregateMotion,
+    markerRequired: [
+      ...(options.required ?? []),
+      ...(options.stable ?? []),
+      ...(options.fixed ?? []),
+      ...(options.unique ?? []),
+      ...(options.motion ?? []),
+      ...(options.flow ?? []),
+    ],
+    invariants: [
+      { type: "required", regions: [...(options.required ?? []), ...inferred] },
+      ...(options.continuousAny ?? []).map(
+        (regions): VisualInvariant<RegionName> => ({ type: "continuous-any", regions }),
+      ),
+      ...(options.unique ? [{ type: "unique" as const, regions: options.unique }] : []),
+      ...(options.stable ? [{ type: "stable" as const, regions: options.stable }] : []),
+      ...(options.fixed
+        ? [{ type: "fixed" as const, regions: options.fixed, tolerance: options.motionTolerance }]
+        : []),
+      { type: "opacity", regions: "all", floor: options.opacityFloor },
+      { type: "continuity", regions: "all" },
+      {
+        type: "motion",
+        regions: options.motion ?? "all",
+        tolerance: options.motionTolerance,
+        maxReversals: options.maxReversals,
+        maxPositionReversals: options.maxPositionReversals,
+      },
+      { type: "label-stability", regions: "all" },
+      ...(options.preserveBottomAnchor ? [{ type: "preserve-bottom-anchor" as const }] : []),
+      ...(options.acquireBottomAnchor ? [{ type: "acquire-bottom-anchor" as const }] : []),
+      ...(options.flow
+        ? [{ type: "flow" as const, regions: options.flow, overlapTolerance: options.overlapTolerance }]
+        : []),
+    ],
+  }
+}
@@ -0,0 +1,47 @@
+export type VisualRegionSample = {
+  present: boolean
+  visible: boolean
+  inViewport: boolean
+  cssHidden?: boolean
+  top: number
+  bottom: number
+  layoutTop?: number
+  layoutBottom?: number
+  width: number
+  height: number
+  opacity: number
+  count: number
+  node: number
+  label: string
+  text: string
+}
+
+export type VisualViewportSample = {
+  top: number
+  bottom: number
+  scrollTop: number
+  scrollHeight: number
+  clientHeight: number
+  distanceFromBottom: number
+}
+
+export type VisualObservation<RegionName extends string = string> = {
+  at: number
+  regions: string extends RegionName
+    ? Record<string, VisualRegionSample>
+    : Partial<Record<RegionName, VisualRegionSample>>
+  viewport?: VisualViewportSample
+}
+
+export type VisualMarker = { at: number; label: string }
+
+export type VisualStabilityTrace<RegionName extends string = string> = {
+  markers: VisualMarker[]
+  samples: VisualObservation<RegionName>[]
+}
+
+export type CapturedFrame = { at: number; data: string }
+
+export type VisualProbeResult<RegionName extends string = string> = VisualStabilityTrace<RegionName> & {
+  frames: CapturedFrame[]
+}
@@ -0,0 +1,226 @@
+import type { Page } from "@playwright/test"
+import { startVisualCapture, stopVisualCapture, type VisualCapture } from "./capture"
+import type { VisualMarker, VisualObservation, VisualProbeResult } from "./model"
+import type { VisualRegionDefinition } from "./regions"
+
+type ProbeWindow<RegionName extends string = string> = Window & {
+  __visualStabilityProbe?: {
+    startedAt: number
+    markers: VisualMarker[]
+    samples: VisualObservation<RegionName>[]
+    stop: () => void
+  }
+}
+
+const captures = new WeakMap<Page, VisualCapture>()
+
+export async function startVisualProbe<Regions extends Record<string, VisualRegionDefinition>>(
+  page: Page,
+  regions: Regions,
+) {
+  await stopCapture(page)
+  await page.evaluate(() => {
+    ;(window as ProbeWindow).__visualStabilityProbe?.stop()
+  })
+  const startedAtEpoch = await page.evaluate((regions) => {
+    const samples: VisualObservation[] = []
+    const markers: VisualMarker[] = []
+    const startedAt = performance.now()
+    const nodes = new WeakMap<Node, number>()
+    const lastBounds = new Map<string, { top: number; bottom: number }>()
+    let nextNode = 1
+    let running = true
+    const round = (value: number) => Math.round(value * 10) / 10
+    const opacity = (element: Element) => Number(getComputedStyle(element).opacity)
+    const sample = () => {
+      if (!running) return
+      setTimeout(() => {
+        if (!running) return
+        const viewport = [...document.querySelectorAll<HTMLElement>(".scroll-view__viewport")].find((element) =>
+          element.querySelector("[data-timeline-row]"),
+        )
+        const viewportRect = viewport?.getBoundingClientRect()
+        samples.push({
+          at: performance.now() - startedAt,
+          viewport: viewport
+            ? {
+                top: round(viewportRect!.top),
+                bottom: round(viewportRect!.bottom),
+                scrollTop: round(viewport.scrollTop),
+                scrollHeight: round(viewport.scrollHeight),
+                clientHeight: round(viewport.clientHeight),
+                distanceFromBottom: round(viewport.scrollHeight - viewport.clientHeight - viewport.scrollTop),
+              }
+            : undefined,
+          regions: Object.fromEntries(
+            Object.entries(regions).map(([name, config]) => {
+              const found = document.querySelector<HTMLElement>(config.selector)
+              const count = document.querySelectorAll(config.selector).length
+              const element = config.closest ? found?.closest<HTMLElement>(config.closest) : found
+              if (!element)
+                return [
+                  name,
+                  {
+                    present: false,
+                    visible: false,
+                    inViewport: false,
+                    top: 0,
+                    bottom: 0,
+                    width: 0,
+                    height: 0,
+                    opacity: 0,
+                    count,
+                    node: 0,
+                    label: "",
+                    text: "",
+                  },
+                ]
+              const rect = element.getBoundingClientRect()
+              const style = getComputedStyle(element)
+              if (rect.height > 0) lastBounds.set(name, { top: rect.top, bottom: rect.bottom })
+              const known = rect.height > 0 ? rect : lastBounds.get(name)
+              const painted = (() => {
+                const result = { top: rect.top, bottom: rect.bottom, left: rect.left, right: rect.right }
+                let parent = element.parentElement
+                while (parent) {
+                  const parentStyle = getComputedStyle(parent)
+                  if (["hidden", "clip", "scroll", "auto"].includes(parentStyle.overflowY)) {
+                    const parentRect = parent.getBoundingClientRect()
+                    result.top = Math.max(result.top, parentRect.top)
+                    result.bottom = Math.min(result.bottom, parentRect.bottom)
+                  }
+                  if (["hidden", "clip", "scroll", "auto"].includes(parentStyle.overflowX)) {
+                    const parentRect = parent.getBoundingClientRect()
+                    result.left = Math.max(result.left, parentRect.left)
+                    result.right = Math.min(result.right, parentRect.right)
+                  }
+                  if (parent === viewport) break
+                  parent = parent.parentElement
+                }
+                if (viewportRect) {
+                  result.top = Math.max(result.top, viewportRect.top)
+                  result.bottom = Math.min(result.bottom, viewportRect.bottom)
+                  result.left = Math.max(result.left, viewportRect.left)
+                  result.right = Math.min(result.right, viewportRect.right)
+                }
+                return result
+              })()
+              const contentOpacity = config.opacitySelectors?.length
+                ? Math.max(
+                    0,
+                    ...config.opacitySelectors.flatMap((selector) =>
+                      [...element.querySelectorAll(selector)].map((node) => {
+                        let value = 1
+                        let current: Element | null = node
+                        while (current) {
+                          value *= opacity(current)
+                          if (current === element) break
+                          current = current.parentElement
+                        }
+                        return value
+                      }),
+                    ),
+                  )
+                : opacity(element)
+              let visibleOpacity = contentOpacity
+              let ancestor = element.parentElement
+              let ancestorHidden = false
+              while (ancestor) {
+                const ancestorStyle = getComputedStyle(ancestor)
+                visibleOpacity *= Number(ancestorStyle.opacity)
+                if (ancestorStyle.display === "none" || ancestorStyle.visibility === "hidden") ancestorHidden = true
+                if (ancestor === viewport) break
+                ancestor = ancestor.parentElement
+              }
+              const cssHidden =
+                ancestorHidden || style.display === "none" || style.visibility === "hidden" || visibleOpacity === 0
+              return [
+                name,
+                {
+                  present: true,
+                  visible:
+                    style.display !== "none" &&
+                    style.visibility !== "hidden" &&
+                    visibleOpacity > 0 &&
+                    painted.right > painted.left &&
+                    painted.bottom > painted.top,
+                  inViewport:
+                    !viewportRect || (!!known && known.bottom > viewportRect.top && known.top < viewportRect.bottom),
+                  cssHidden,
+                  top: round(painted.top),
+                  bottom: round(painted.bottom),
+                  layoutTop: round(rect.top),
+                  layoutBottom: round(rect.bottom),
+                  width: round(painted.right - painted.left),
+                  height: round(painted.bottom - painted.top),
+                  opacity: round(visibleOpacity),
+                  count,
+                  node: (() => {
+                    const current = nodes.get(element)
+                    if (current) return current
+                    nodes.set(element, nextNode)
+                    return nextNode++
+                  })(),
+                  label: element.getAttribute("aria-label") ?? "",
+                  text: (element.textContent ?? "").trim().replace(/\s+/g, " ").slice(0, 500),
+                },
+              ]
+            }),
+          ),
+        })
+        requestAnimationFrame(sample)
+      }, 0)
+    }
+    ;(window as ProbeWindow).__visualStabilityProbe = {
+      startedAt,
+      markers,
+      samples,
+      stop: () => {
+        running = false
+      },
+    }
+    requestAnimationFrame(sample)
+    return new Promise<number>((resolve) => {
+      const ready = () => {
+        if (samples.length > 0) return resolve(performance.timeOrigin + startedAt)
+        requestAnimationFrame(ready)
+      }
+      ready()
+    })
+  }, regions)
+  const capture = await startVisualCapture(page, startedAtEpoch)
+  if (capture) captures.set(page, capture)
+}
+
+export async function stopVisualProbe<RegionName extends string = string>(
+  page: Page,
+): Promise<VisualProbeResult<RegionName>> {
+  return page
+    .evaluate(() => {
+      const probe = (window as ProbeWindow).__visualStabilityProbe
+      if (!probe) throw new Error("Visual stability probe is not running")
+      probe.stop()
+      return { markers: probe.markers, samples: probe.samples }
+    })
+    .then(
+      async (trace) => ({ ...trace, frames: await stopCapture(page) }) as unknown as VisualProbeResult<RegionName>,
+      async (error: unknown) => {
+        await stopCapture(page)
+        throw error
+      },
+    )
+}
+
+export async function markVisualProbe(page: Page, label: string) {
+  await page.evaluate((label) => {
+    const probe = (window as ProbeWindow).__visualStabilityProbe
+    if (!probe) return
+    probe.markers.push({ at: performance.now() - probe.startedAt, label })
+  }, label)
+}
+
+async function stopCapture(page: Page) {
+  const capture = captures.get(page)
+  if (capture) captures.delete(page)
+  return stopVisualCapture(capture)
+}
@@ -0,0 +1,18 @@
+export type VisualRegionDefinition = {
+  selector: string
+  closest?: string
+  opacitySelectors?: readonly string[]
+}
+
+export function defineVisualRegions<const Regions extends Record<string, VisualRegionDefinition>>(regions: Regions) {
+  return regions
+}
+
+export function mapVisualRegions<const Regions extends Record<string, VisualRegionDefinition>, Result>(
+  regions: Regions,
+  map: (region: Regions[keyof Regions], name: keyof Regions) => Result,
+) {
+  return Object.fromEntries(
+    Object.entries(regions).map(([name, region]) => [name, map(region as Regions[keyof Regions], name)]),
+  ) as { [Name in keyof Regions]: Result }
+}
@@ -0,0 +1,63 @@
+import { expect, type TestInfo } from "@playwright/test"
+import { writeFile } from "node:fs/promises"
+import { analyzeVisualObservations, analyzeVisualTraceByMarker } from "./analyzer"
+import type { VisualPlan } from "./invariant"
+import type { VisualProbeResult } from "./model"
+
+export async function reportVisualStability<RegionName extends string>(
+  testInfo: TestInfo,
+  name: string,
+  result: VisualProbeResult<RegionName>,
+  plan: VisualPlan<RegionName>,
+) {
+  const trace = { markers: result.markers, samples: result.samples }
+  const issues = plan.perMarker
+    ? analyzeVisualTraceByMarker(trace, plan)
+    : analyzeVisualObservations(result.samples, plan)
+  const tracePath = testInfo.outputPath(`${name}-visual-trace.json`)
+  const issuesPath = testInfo.outputPath(`${name}-visual-issues.json`)
+  await writeFile(tracePath, JSON.stringify(trace, null, 2))
+  await writeFile(
+    issuesPath,
+    JSON.stringify({ issues, markers: result.markers, capturedFrameCount: result.frames.length }, null, 2),
+  )
+  await testInfo.attach(`${name}-visual-trace`, { path: tracePath, contentType: "application/json" })
+  await testInfo.attach(`${name}-visual-issues`, { path: issuesPath, contentType: "application/json" })
+  if (issues.length) await attachViolationFrames(testInfo, name, result, issues)
+  expect(issues, `${name}: ${issues.join("\n")}`).toEqual([])
+}
+
+async function attachViolationFrames<RegionName extends string>(
+  testInfo: TestInfo,
+  name: string,
+  result: VisualProbeResult<RegionName>,
+  issues: string[],
+) {
+  if (result.frames.length === 0) return
+  const targets = [
+    ...new Set(
+      issues.flatMap((issue) => {
+        const match = issue.match(/ at (\d+)ms/)
+        if (match) return [Number(match[1])]
+        const marker = result.markers.find((item) => issue.startsWith(`${item.label}:`))
+        return marker ? [marker.at] : []
+      }),
+    ),
+  ].slice(0, 6)
+  for (const [violation, target] of targets.entries()) {
+    const nearest = result.frames.reduce(
+      (best, frame, index) => (Math.abs(frame.at - target) < Math.abs(result.frames[best]!.at - target) ? index : best),
+      0,
+    )
+    for (const [label, index] of [
+      ["before", Math.max(0, nearest - 1)],
+      ["violation", nearest],
+      ["after", Math.min(result.frames.length - 1, nearest + 1)],
+    ] as const) {
+      await testInfo.attach(`${name}-${violation + 1}-${label}-${Math.round(result.frames[index]!.at)}ms`, {
+        body: Buffer.from(result.frames[index]!.data, "base64"),
+        contentType: "image/jpeg",
+      })
+    }
+  }
+}
@@ -0,0 +1,20 @@
+import type { Page, TestInfo } from "@playwright/test"
+import type { VisualPlan } from "./invariant"
+import { startVisualProbe, stopVisualProbe } from "./probe"
+import type { VisualRegionDefinition } from "./regions"
+import { reportVisualStability } from "./reporter"
+
+export async function runVisualStabilityScenario<const Regions extends Record<string, VisualRegionDefinition>>(input: {
+  page: Page
+  testInfo: TestInfo
+  name: string
+  regions: Regions
+  plan: VisualPlan<Extract<keyof Regions, string>>
+  run: () => Promise<void>
+}) {
+  await startVisualProbe(input.page, input.regions)
+  await input.run()
+  const result = await stopVisualProbe<Extract<keyof Regions, string>>(input.page)
+  await reportVisualStability(input.testInfo, input.name, result, input.plan)
+  return result
+}
@@ -1,6 +1,6 @@
 {
  "name": "@opencode-ai/app",
-  "version": "1.17.11",
+  "version": "1.17.13",
  "description": "",
  "type": "module",
  "exports": {
@@ -13,6 +13,7 @@
  },
  "scripts": {
    "typecheck": "tsgo -b",
+    "typecheck:e2e": "tsgo -p e2e/tsconfig.json",
    "start": "vite",
    "dev": "vite",
    "build": "vite build",
@@ -25,6 +26,7 @@
    "test:e2e:local": "playwright test",
    "test:e2e:ui": "playwright test --ui",
    "test:e2e:report": "playwright show-report e2e/playwright-report",
+    "test:stability": "bun test ./e2e/performance/unit/visual-stability.test.ts && playwright test --config e2e/performance/timeline-stability/playwright.config.ts",
    "test:bench": "bun test ./e2e/performance/unit && playwright test --config e2e/performance/playwright.config.ts"
  },
  "license": "MIT",
@@ -38,6 +40,7 @@
    "@types/luxon": "catalog:",
    "@types/node": "catalog:",
    "@typescript/native-preview": "catalog:",
+    "tw-animate-css": "1.4.0",
    "typescript": "catalog:",
    "vite": "catalog:",
    "vite-plugin-icons-spritesheet": "3.0.1",
@@ -50,6 +53,7 @@
    "@dnd-kit/solid": "0.5.0",
    "@kobalte/core": "catalog:",
    "@opencode-ai/core": "workspace:*",
+    "@opencode-ai/schema": "workspace:*",
    "@opencode-ai/sdk": "workspace:*",
    "@opencode-ai/session-ui": "workspace:*",
    "@opencode-ai/ui": "workspace:*",
@@ -28,11 +28,11 @@ import {
  Show,
 } from "solid-js"
 import { Dynamic } from "solid-js/web"
-import { CommandProvider } from "@/context/command"
+import { CommandProvider, useCommand, type CommandOption } from "@/context/command"
 import { CommentsProvider } from "@/context/comments"
 import { FileProvider } from "@/context/file"
-import { ServerSDKProvider, useServerSDK } from "@/context/server-sdk"
-import { ServerSyncProvider, useServerSync } from "@/context/server-sync"
+import { ServerSDKProvider } from "@/context/server-sdk"
+import { ServerSyncProvider } from "@/context/server-sync"
 import { GlobalProvider, useGlobal } from "@/context/global"
 import { HighlightsProvider } from "@/context/highlights"
 import { LanguageProvider, type Locale, useLanguage } from "@/context/language"
@@ -40,10 +40,10 @@ import { LayoutProvider } from "@/context/layout"
 import { ModelsProvider } from "@/context/models"
 import { NotificationProvider } from "@/context/notification"
 import { PermissionProvider } from "@/context/permission"
+import { usePlatform } from "@/context/platform"
 import { PromptProvider } from "@/context/prompt"
 import { ServerConnection, ServerProvider, serverName, useServer } from "@/context/server"
 import { SettingsProvider, useSettings } from "@/context/settings"
-import { TerminalProvider } from "@/context/terminal"
 import { TabsProvider, useTabs, type DraftTab } from "@/context/tabs"
 import { SDKProvider, useSDK } from "@/context/sdk"
 import { WslServersProvider } from "@/wsl/context"
@@ -52,16 +52,9 @@ import LegacyLayout from "@/pages/layout"
 import NewLayout from "@/pages/layout-new"
 import { ErrorPage } from "./pages/error"
 import { useCheckServerHealth } from "./utils/server-health"
-import {
-  legacySessionHref,
-  legacySessionServer,
-  requireServerKey,
-  selectSessionLineage,
-  sessionHref,
-} from "./utils/session-route"
-import { isSessionNotFoundError } from "./utils/server-errors"
+import { legacySessionServer, requireServerKey, sessionHref } from "./utils/session-route"

-import Session from "@/pages/session"
+import { SessionPage, TargetSessionRoute as TargetSessionRouteContent } from "@/pages/session"
 import { NewHome, LegacyHome } from "@/pages/home"

 const NewSession = lazy(() => import("@/pages/new-session"))
@@ -95,11 +88,7 @@ const SessionRoute = () => {
    tabs.newDraft({ server: server.key, directory: sdk().directory }, search.prompt)
  })

-  return (
-    <SessionProviders>
-      <Session />
-    </SessionProviders>
-  )
+  return <SessionPage />
 }

 const TargetSessionRoute = () => {
@@ -114,76 +103,13 @@ const TargetSessionRoute = () => {
    <Show when={requireServerKey(params.serverKey)} keyed>
      <ServerSDKProvider server={conn}>
        <ServerSyncProvider server={conn}>
-          <ResolvedTargetSessionRoute />
+          <TargetSessionRouteContent />
        </ServerSyncProvider>
      </ServerSDKProvider>
    </Show>
  )
 }

-function ResolvedTargetSessionRoute() {
-  const params = useParams<{ serverKey: string; id: string }>()
-  const settings = useSettings()
-  const tabs = useTabs()
-  const sync = useServerSync()
-  const serverKey = createMemo(() => requireServerKey(params.serverKey))
-  const cached = createMemo(() => sync().session.lineage.peek(params.id))
-  const [resolved] = createResource(
-    () => {
-      if (cached()) return
-      return { id: params.id, server: serverKey(), sync: sync() }
-    },
-    ({ id, server, sync }) =>
-      sync.session.lineage.resolve(id).catch((error) => {
-        if (isSessionNotFoundError(error, id)) tabs.removeSessionTab({ server, sessionId: id })
-        throw error
-      }),
-  )
-  const current = createMemo(() => selectSessionLineage(params.id, cached(), resolved()))
-  const directory = createMemo(() => current()?.session.directory)
-  const targetDirectory = () => directory()!
-
-  createEffect(() => {
-    const session = current()
-    if (!session) return
-    tabs.addSessionTab({
-      server: serverKey(),
-      sessionId: session.root.id,
-    })
-  })
-
-  return (
-    <TargetServerScopedProviders directory={directory} sessionID={() => params.id}>
-      <Show when={!!current() || resolved.state !== "errored"} fallback={<ErrorPage error={resolved.error} />}>
-        <Show when={directory()}>
-          <Show
-            when={settings.general.newLayoutDesigns()}
-            fallback={<Navigate href={legacySessionHref(directory()!, params.id)} />}
-          >
-            <SDKProvider directory={targetDirectory}>
-              <DirectoryDataProvider directory={targetDirectory} server={serverKey}>
-                <TargetSessionPage />
-              </DirectoryDataProvider>
-            </SDKProvider>
-          </Show>
-        </Show>
-      </Show>
-    </TargetServerScopedProviders>
-  )
-}
-
-function TargetSessionPage() {
-  const sdk = useSDK()
-  const serverSDK = useServerSDK()
-  return (
-    <Show when={`${serverSDK().scope}\0${sdk().directory}`} keyed>
-      <SessionProviders>
-        <Session />
-      </SessionProviders>
-    </Show>
-  )
-}
-
 // Wraps the non-draft routes. They are gated on (and keyed to) the globally selected
 // server via ServerKey, then provide the server-scoped shell (Permission/Layout/
 // Notification/Models + the visual Layout) for that server.
@@ -197,10 +123,10 @@ function SelectedServerProviders(props: ParentProps) {
  )
 }

-function LegacyServerLayout(props: ParentProps) {
+function LegacyServerLayout(props: ParentProps<{ serverScoped?: JSX.Element }>) {
  return (
    <SelectedServerProviders>
-      <LegacyServerScopedShell>{props.children}</LegacyServerScopedShell>
+      <LegacyServerScopedShell serverScoped={props.serverScoped}>{props.children}</LegacyServerScopedShell>
    </SelectedServerProviders>
  )
 }
@@ -231,7 +157,7 @@ function ResolvedDraftRoute(props: { draft: DraftTab }) {
    <Show when={`${props.draft.server}\0${props.draft.directory}`} keyed>
      <ServerSDKProvider server={conn}>
        <ServerSyncProvider server={conn}>
-          <TargetServerScopedProviders directory={directory}>
+          <DraftServerScopedProviders directory={directory}>
            <SDKProvider directory={directory}>
              <DirectoryDataProvider directory={directory} server={serverKey}>
                <DraftProviders>
@@ -239,7 +165,7 @@ function ResolvedDraftRoute(props: { draft: DraftTab }) {
                </DraftProviders>
              </DirectoryDataProvider>
            </SDKProvider>
-          </TargetServerScopedProviders>
+          </DraftServerScopedProviders>
        </ServerSyncProvider>
      </ServerSDKProvider>
    </Show>
@@ -300,25 +226,49 @@ function SharedProviders(props: ParentProps) {
    <>
      <BodyDesignClass />
      <CommandProvider>
+        <DesktopCommands />
        <HighlightsProvider>{props.children}</HighlightsProvider>
      </CommandProvider>
    </>
  )
 }

+function DesktopCommands() {
+  const command = useCommand()
+  const language = useLanguage()
+  const platform = usePlatform()
+
+  command.register("desktop", () => {
+    const commands: CommandOption[] = []
+    if (platform.platform === "desktop" && platform.exportDebugLogs) {
+      commands.push({
+        id: "logs.export",
+        title: "Export logs",
+        category: language.t("command.category.settings"),
+        onSelect: () => {
+          void platform.exportDebugLogs?.()
+        },
+      })
+    }
+    return commands
+  })
+
+  return null
+}
+
 // Server-scoped providers shared by the legacy shell and the top-level new shell.
 type ServerScopedShellProps = ParentProps<{
  directory?: () => string | undefined
  sessionID?: () => string | undefined
+  serverScoped?: JSX.Element
 }>

 function ServerScopedProviders(props: ServerScopedShellProps) {
  return (
    <PermissionProvider directory={props.directory}>
      <LayoutProvider>
-        <NotificationProvider directory={props.directory} sessionID={props.sessionID}>
-          <ModelsProvider directory={props.directory}>{props.children}</ModelsProvider>
-        </NotificationProvider>
+        {props.serverScoped}
+        <ModelsProvider directory={props.directory}>{props.children}</ModelsProvider>
      </LayoutProvider>
    </PermissionProvider>
  )
@@ -326,44 +276,30 @@ function ServerScopedProviders(props: ServerScopedShellProps) {

 function LegacyServerScopedShell(props: ServerScopedShellProps) {
  return (
-    <ServerScopedProviders directory={props.directory} sessionID={props.sessionID}>
+    <ServerScopedProviders directory={props.directory} sessionID={props.sessionID} serverScoped={props.serverScoped}>
      <LegacyLayout>{props.children}</LegacyLayout>
    </ServerScopedProviders>
  )
 }

-function NewAppLayout(props: ParentProps) {
+function NewAppLayout(props: ParentProps<{ serverScoped?: JSX.Element }>) {
  return (
    <SelectedServerProviders>
-      <ServerScopedProviders>
+      <ServerScopedProviders serverScoped={props.serverScoped}>
        <NewLayout>{props.children}</NewLayout>
      </ServerScopedProviders>
    </SelectedServerProviders>
  )
 }

-function TargetServerScopedProviders(props: ServerScopedShellProps) {
+function DraftServerScopedProviders(props: ParentProps<{ directory?: () => string | undefined }>) {
  return (
    <PermissionProvider directory={props.directory}>
-      <NotificationProvider directory={props.directory} sessionID={props.sessionID}>
-        <ModelsProvider directory={props.directory}>{props.children}</ModelsProvider>
-      </NotificationProvider>
+      <ModelsProvider directory={props.directory}>{props.children}</ModelsProvider>
    </PermissionProvider>
  )
 }

-function SessionProviders(props: ParentProps) {
-  return (
-    <TerminalProvider>
-      <FileProvider>
-        <PromptProvider>
-          <CommentsProvider>{props.children}</CommentsProvider>
-        </PromptProvider>
-      </FileProvider>
-    </TerminalProvider>
-  )
-}
-
 // The draft page only renders the prompt composer, so it drops TerminalProvider.
 // FileProvider and CommentsProvider stay because PromptInput uses file search and comment context.
 function DraftProviders(props: ParentProps) {
@@ -410,7 +346,7 @@ export function AppBaseProviders(props: ParentProps<{ locale?: Locale }>) {
  )
 }

-function ConnectionGate(props: ParentProps<{ disableHealthCheck?: boolean }>) {
+function ConnectionGate(props: ParentProps<{ disableHealthCheck?: boolean; startup?: Promise<void> }>) {
  const server = useServer()
  const checkServerHealth = useCheckServerHealth()

@@ -439,34 +375,45 @@ function ConnectionGate(props: ParentProps<{ disableHealthCheck?: boolean }>) {
  const checking = createMemo(
    () => checkMode() === "blocking" && ["unresolved", "pending"].includes(startupHealthCheck.state),
  )
+  const [startup] = createResource(async () => {
+    if (!props.startup) return true
+    await props.startup.catch((error) => {
+      console.error("[startup] startup gate failed", error)
+    })
+    return true
+  })
+  const startupChecking = createMemo(
+    () => startupHealthCheck.latest === true && ["unresolved", "pending"].includes(startup.state),
+  )
+  const loading = createMemo(() => checking() || startupChecking())

  return (
-    <Show
-      when={!checking()}
-      fallback={
-        <div class="h-dvh w-screen flex flex-col items-center justify-center bg-background-base">
+    <>
+      <Show when={!checking()}>
+        <Show
+          when={startupHealthCheck.latest}
+          fallback={
+            <ConnectionError
+              onRetry={() => {
+                if (checkMode() === "background") void healthCheckActions.refetch()
+              }}
+              onServerSelected={(key) => {
+                setCheckMode("blocking")
+                server.setActive(key)
+                void healthCheckActions.refetch()
+              }}
+            />
+          }
+        >
+          {props.children}
+        </Show>
+      </Show>
+      <Show when={loading()}>
+        <div class="fixed inset-0 z-[9999] flex flex-col items-center justify-center bg-background-base">
          <Splash class="w-16 h-20 opacity-50 animate-pulse" />
        </div>
-      }
-    >
-      <Show
-        when={startupHealthCheck.latest}
-        fallback={
-          <ConnectionError
-            onRetry={() => {
-              if (checkMode() === "background") void healthCheckActions.refetch()
-            }}
-            onServerSelected={(key) => {
-              setCheckMode("blocking")
-              server.setActive(key)
-              void healthCheckActions.refetch()
-            }}
-          />
-        }
-      >
-        {props.children}
      </Show>
-    </Show>
+    </>
  )
 }

@@ -533,6 +480,8 @@ export function AppInterface(props: {
  servers?: Array<ServerConnection.Any>
  router?: Component<BaseRouterProps>
  disableHealthCheck?: boolean
+  startup?: Promise<void>
+  serverScoped?: JSX.Element
 }) {
  // The visual new layout lives in the router root so it remains mounted across
  // route changes. Draft and session routes override only their server-bound data
@@ -554,21 +503,23 @@ export function AppInterface(props: {
    >
      <GlobalProvider>
        <SettingsProvider>
-          <ConnectionGate disableHealthCheck={props.disableHealthCheck}>
+          <ConnectionGate disableHealthCheck={props.disableHealthCheck} startup={props.startup}>
            <Show when={useSettings().general.newLayoutDesigns().toString()} keyed>
              <Dynamic
                component={props.router ?? Router}
                root={(routerProps) => (
                  <TabsProvider>
-                    <ServerShell>
-                      <Show when={useSettings().general.newLayoutDesigns()} fallback={routerProps.children}>
-                        <NewAppLayout>{routerProps.children}</NewAppLayout>
-                      </Show>
-                    </ServerShell>
+                    <NotificationProvider>
+                      <ServerShell>
+                        <Show when={useSettings().general.newLayoutDesigns()} fallback={routerProps.children}>
+                          <NewAppLayout serverScoped={props.serverScoped}>{routerProps.children}</NewAppLayout>
+                        </Show>
+                      </ServerShell>
+                    </NotificationProvider>
                  </TabsProvider>
                )}
              >
-                <Routes />
+                <Routes serverScoped={props.serverScoped} />
              </Dynamic>
            </Show>
          </ConnectionGate>
@@ -578,12 +529,16 @@ export function AppInterface(props: {
  )
 }

-function Routes() {
+function Routes(props: { serverScoped?: JSX.Element }) {
  const settings = useSettings()

  return (
    <>
-      <Route component={LegacyServerLayout}>
+      <Route
+        component={(routeProps) => (
+          <LegacyServerLayout serverScoped={props.serverScoped}>{routeProps.children}</LegacyServerLayout>
+        )}
+      >
        <Show when={!settings.general.newLayoutDesigns()}>{<Route path="/" component={LegacyHome} />}</Show>
        <Route path="/:dir" component={DirectoryLayout}>
          <Route path="/" component={() => <Navigate href="session" />} />
@@ -3,6 +3,7 @@ import { batch, createEffect, onCleanup, onMount } from "solid-js"
 import { createStore } from "solid-js/store"
 import { makeEventListener } from "@solid-primitives/event-listener"
 import { Tooltip } from "@opencode-ai/ui/tooltip"
+import { TooltipV2 } from "@opencode-ai/ui/v2/tooltip-v2"
 import { useLanguage } from "@/context/language"

 type Mem = Performance & {
@@ -51,31 +52,62 @@ const bad = (n: number | undefined, limit: number, low = false) => {

 const session = (path: string) => path.includes("/session")

-function Cell(props: { bad?: boolean; dim?: boolean; label: string; tip: string; value: string; wide?: boolean }) {
-  return (
-    <Tooltip value={props.tip} placement="top">
+function Cell(props: {
+  bad?: boolean
+  dim?: boolean
+  inline?: boolean
+  label: string
+  tip: string
+  value: string
+  wide?: boolean
+}) {
+  const content = () => (
+    <div
+      classList={{
+        "flex min-w-0 items-center": true,
+        "min-h-[20px] w-fit flex-row justify-start gap-1.5 px-1.5 py-0.5 text-left": !!props.inline,
+        "justify-center text-center": !props.inline,
+        "min-h-[42px] w-full flex-col rounded-[8px] px-0.5 py-1": !props.inline,
+        "col-span-2": !!props.wide && !props.inline,
+      }}
+    >
      <div
        classList={{
-          "flex min-h-[42px] w-full min-w-0 flex-col items-center justify-center rounded-[8px] px-0.5 py-1 text-center": true,
-          "col-span-2": !!props.wide,
+          "text-[10px] leading-none font-black uppercase tracking-[0.04em] opacity-70": true,
        }}
      >
-        <div class="text-[10px] leading-none font-black uppercase tracking-[0.04em] opacity-70">{props.label}</div>
-        <div
-          classList={{
-            "text-[13px] leading-none font-bold tabular-nums sm:text-[14px]": true,
-            "text-text-on-critical-base": !!props.bad,
-            "opacity-70": !!props.dim,
-          }}
-        >
-          {props.value}
-        </div>
+        {props.label}
      </div>
+      <div
+        classList={{
+          "uppercase leading-none font-bold tabular-nums": true,
+          "text-[11px]": !!props.inline,
+          "text-[13px] sm:text-[14px]": !props.inline,
+          "text-text-on-critical-base": !!props.bad,
+          "opacity-70": !!props.dim,
+        }}
+      >
+        {props.value}
+      </div>
+    </div>
+  )
+
+  if (props.inline) {
+    return (
+      <TooltipV2 value={props.tip} placement="top">
+        {content()}
+      </TooltipV2>
+    )
+  }
+
+  return (
+    <Tooltip value={props.tip} placement="top">
+      {content()}
    </Tooltip>
  )
 }

-export function DebugBar() {
+export function DebugBar(props: { inline?: boolean } = {}) {
  const language = useLanguage()
  const location = useLocation()
  const routing = useIsRouting()
@@ -101,7 +133,7 @@ export function DebugBar() {
    },
  })

-  const na = () => language.t("debugBar.na")
+  const na = () => language.t("debugBar.na").toUpperCase()
  const heap = () => (state.heap.limit ? (state.heap.used ?? 0) / state.heap.limit : undefined)
  const heapv = () => {
    const value = heap()
@@ -363,15 +395,30 @@ export function DebugBar() {
  return (
    <aside
      aria-label={language.t("debugBar.ariaLabel")}
-      class="pointer-events-auto fixed bottom-3 right-3 z-50 hidden w-[308px] max-w-[calc(100vw-1.5rem)] overflow-hidden rounded-xl border border-border-base bg-surface-raised-stronger-non-alpha p-0.5 text-text-strong shadow-[var(--shadow-lg-border-base)] md:block sm:bottom-4 sm:right-4 sm:w-[324px]"
+      classList={{
+        "pointer-events-auto hidden overflow-hidden text-text-strong md:block": true,
+        "mt-[-6px] w-full shrink-0 px-3 py-1": !!props.inline,
+        "fixed bottom-3 right-3 z-50 w-[308px] max-w-[calc(100vw-1.5rem)] rounded-xl border border-border-base bg-surface-raised-stronger-non-alpha p-0.5 shadow-[var(--shadow-lg-border-base)] sm:bottom-4 sm:right-4 sm:w-[324px]":
+          !props.inline,
+      }}
    >
-      <div class="grid grid-cols-5 gap-px font-mono">
+      <div
+        classList={{
+          "font-mono": true,
+          "gap-[9px]": !!props.inline,
+          "gap-px": !props.inline,
+          "flex w-full flex-nowrap items-center justify-start": !!props.inline,
+          "grid-cols-5": !props.inline,
+          grid: !props.inline,
+        }}
+      >
        <Cell
          label={language.t("debugBar.nav.label")}
          tip={language.t("debugBar.nav.tip")}
          value={navv()}
          bad={bad(state.nav.dur, 400)}
          dim={state.nav.dur === undefined && !state.nav.pending}
+          inline={props.inline}
        />
        <Cell
          label={language.t("debugBar.fps.label")}
@@ -379,6 +426,7 @@ export function DebugBar() {
          value={state.fps === undefined ? na() : `${Math.round(state.fps)}`}
          bad={bad(state.fps, 50, true)}
          dim={state.fps === undefined}
+          inline={props.inline}
        />
        <Cell
          label={language.t("debugBar.frame.label")}
@@ -386,6 +434,7 @@ export function DebugBar() {
          value={time(state.gap) ?? na()}
          bad={bad(state.gap, 50)}
          dim={state.gap === undefined}
+          inline={props.inline}
        />
        <Cell
          label={language.t("debugBar.jank.label")}
@@ -393,6 +442,7 @@ export function DebugBar() {
          value={state.jank === undefined ? na() : `${state.jank}`}
          bad={bad(state.jank, 8)}
          dim={state.jank === undefined}
+          inline={props.inline}
        />
        <Cell
          label={language.t("debugBar.long.label")}
@@ -400,6 +450,7 @@ export function DebugBar() {
          value={longv()}
          bad={bad(state.long.block, 200)}
          dim={state.long.count === undefined}
+          inline={props.inline}
        />
        <Cell
          label={language.t("debugBar.delay.label")}
@@ -407,6 +458,7 @@ export function DebugBar() {
          value={time(state.delay) ?? na()}
          bad={bad(state.delay, 100)}
          dim={state.delay === undefined}
+          inline={props.inline}
        />
        <Cell
          label={language.t("debugBar.inp.label")}
@@ -414,6 +466,7 @@ export function DebugBar() {
          value={time(state.inp) ?? na()}
          bad={bad(state.inp, 200)}
          dim={state.inp === undefined}
+          inline={props.inline}
        />
        <Cell
          label={language.t("debugBar.cls.label")}
@@ -421,6 +474,7 @@ export function DebugBar() {
          value={state.cls === undefined ? na() : state.cls.toFixed(2)}
          bad={bad(state.cls, 0.1)}
          dim={state.cls === undefined}
+          inline={props.inline}
        />
        <Cell
          label={language.t("debugBar.mem.label")}
@@ -435,6 +489,7 @@ export function DebugBar() {
          value={heapv()}
          bad={bad(heap(), 0.8)}
          dim={state.heap.used === undefined}
+          inline={props.inline}
          wide
        />
      </div>
@@ -65,6 +65,7 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc
  const [store, setStore] = createStore({
    methodIndex: undefined as undefined | number,
    authorization: undefined as undefined | ProviderAuthAuthorization,
+    promptInputs: undefined as undefined | Record<string, string>,
    state: "pending" as undefined | "pending" | "complete" | "error" | "prompt",
    error: undefined as string | undefined,
  })
@@ -73,6 +74,7 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc
    | { type: "method.select"; index: number }
    | { type: "method.reset" }
    | { type: "auth.prompt" }
+    | { type: "auth.inputs"; inputs: Record<string, string> }
    | { type: "auth.pending" }
    | { type: "auth.complete"; authorization: ProviderAuthAuthorization }
    | { type: "auth.error"; error: string }
@@ -83,6 +85,7 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc
        if (action.type === "method.select") {
          draft.methodIndex = action.index
          draft.authorization = undefined
+          draft.promptInputs = undefined
          draft.state = undefined
          draft.error = undefined
          return
@@ -90,6 +93,7 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc
        if (action.type === "method.reset") {
          draft.methodIndex = undefined
          draft.authorization = undefined
+          draft.promptInputs = undefined
          draft.state = undefined
          draft.error = undefined
          return
@@ -99,6 +103,12 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc
          draft.error = undefined
          return
        }
+        if (action.type === "auth.inputs") {
+          draft.promptInputs = action.inputs
+          draft.state = undefined
+          draft.error = undefined
+          return
+        }
        if (action.type === "auth.pending") {
          draft.state = "pending"
          draft.error = undefined
@@ -151,6 +161,15 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc
    const method = methods()[index]
    dispatch({ type: "method.select", index })

+    if (method.type === "api" && method.prompts?.length) {
+      if (!inputs) {
+        dispatch({ type: "auth.prompt" })
+        return
+      }
+      dispatch({ type: "auth.inputs", inputs })
+      return
+    }
+
    if (method.type === "oauth") {
      if (method.prompts?.length && !inputs) {
        dispatch({ type: "auth.prompt" })
@@ -190,7 +209,7 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc
    }
  }

-  function OAuthPromptsView() {
+  function AuthPromptsView() {
    const [formStore, setFormStore] = createStore({
      value: {} as Record<string, string>,
      index: 0,
@@ -198,8 +217,7 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc

    const prompts = createMemo<NonNullable<ProviderAuthMethod["prompts"]>>(() => {
      const value = method()
-      if (value?.type !== "oauth") return []
-      return value.prompts ?? []
+      return value?.prompts ?? []
    })
    const matches = (prompt: NonNullable<ReturnType<typeof prompts>[number]>, value: Record<string, string>) => {
      if (!prompt.when) return true
@@ -230,6 +248,10 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc
        setFormStore("index", next)
        return
      }
+      if (method()?.type === "api") {
+        dispatch({ type: "auth.inputs", inputs: value })
+        return
+      }
      await selectMethod(store.methodIndex, value)
    }

@@ -414,6 +436,7 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc
        auth: {
          type: "api",
          key: apiKey,
+          ...(store.promptInputs ? { metadata: store.promptInputs } : {}),
        },
      })
      await complete()
@@ -622,7 +645,7 @@ export function DialogConnectProvider(props: { provider: string; directory?: Acc
                </div>
              </Match>
              <Match when={store.state === "prompt"}>
-                <OAuthPromptsView />
+                <AuthPromptsView />
              </Match>
              <Match when={store.state === "error"}>
                <div class="text-14-regular text-text-base">
@@ -3,13 +3,26 @@ import { List } from "@opencode-ai/ui/list"
 import { Switch } from "@opencode-ai/ui/switch"
 import { Tooltip } from "@opencode-ai/ui/tooltip"
 import { Button } from "@opencode-ai/ui/button"
-import type { Component } from "solid-js"
+import { ButtonV2 } from "@opencode-ai/ui/v2/button-v2"
+import { Dialog as DialogV2, DialogBody, DialogHeader, DialogTitleGroup } from "@opencode-ai/ui/v2/dialog-v2"
+import { Icon as IconV2 } from "@opencode-ai/ui/v2/icon"
+import { IconButtonV2 } from "@opencode-ai/ui/v2/icon-button-v2"
+import { TextInputV2 } from "@opencode-ai/ui/v2/text-input-v2"
+import { Switch as SwitchV2 } from "@opencode-ai/ui/v2/switch-v2"
+import { ProviderIcon } from "@opencode-ai/ui/provider-icon"
+import { useFilteredList } from "@opencode-ai/ui/hooks"
+import { For, Show, type Component } from "solid-js"
 import { useLocal } from "@/context/local"
 import { popularProviders } from "@/hooks/use-providers"
 import { useLanguage } from "@/context/language"
 import { useDialog } from "@opencode-ai/ui/context/dialog"
 import { DialogSelectProvider } from "./dialog-select-provider"
 import { decode64 } from "@/utils/base64"
+import { SettingsListV2 } from "./settings-v2/parts/list"
+import { SettingsRowV2 } from "./settings-v2/parts/row"
+import "./settings-v2/settings-v2.css"
+
+type ModelItem = ReturnType<ReturnType<typeof useLocal>["model"]["list"]>[number]

 export const DialogManageModels: Component = () => {
  const local = useLocal()
@@ -102,3 +115,151 @@ export const DialogManageModels: Component = () => {
    </Dialog>
  )
 }
+
+export const DialogManageModelsV2: Component = () => {
+  const local = useLocal()
+  const language = useLanguage()
+  const dialog = useDialog()
+  const directory = () => decode64(local.slug())
+
+  const handleConnectProvider = () => {
+    dialog.show(() => <DialogSelectProvider directory={directory} />)
+  }
+  const providerList = (providerID: string) => local.model.list().filter((x) => x.provider.id === providerID)
+  const providerVisible = (providerID: string) =>
+    providerList(providerID).every((x) => local.model.visible({ modelID: x.id, providerID: x.provider.id }))
+  const setProviderVisibility = (providerID: string, checked: boolean) => {
+    providerList(providerID).forEach((x) => {
+      local.model.setVisibility({ modelID: x.id, providerID: x.provider.id }, checked)
+    })
+  }
+  const setModelVisibility = (item: ModelItem, checked: boolean) => {
+    local.model.setVisibility({ modelID: item.id, providerID: item.provider.id }, checked)
+  }
+  const list = useFilteredList<ModelItem>({
+    items: () => local.model.list(),
+    key: (x) => `${x.provider.id}:${x.id}`,
+    filterKeys: ["provider.name", "name", "id"],
+    sortBy: (a, b) => a.name.localeCompare(b.name),
+    groupBy: (x) => x.provider.id,
+    sortGroupsBy: (a, b) => {
+      const aRank = popularProviders.indexOf(a.category)
+      const bRank = popularProviders.indexOf(b.category)
+      const aPopular = aRank >= 0
+      const bPopular = bRank >= 0
+      if (aPopular && !bPopular) return -1
+      if (!aPopular && bPopular) return 1
+      return aRank - bRank
+    },
+  })
+
+  return (
+    <DialogV2 size="large" variant="settings" class="settings-v2-manage-models-dialog">
+      <DialogHeader hideClose={true} closeLabel={language.t("common.close")}>
+        <DialogTitleGroup
+          title={language.t("dialog.model.manage")}
+          description={language.t("dialog.model.manage.description")}
+        />
+        <ButtonV2 variant="neutral" icon="plus" onClick={handleConnectProvider}>
+          {language.t("command.provider.connect")}
+        </ButtonV2>
+      </DialogHeader>
+      <DialogBody class="flex min-h-0 flex-1 flex-col">
+        <div class="px-4 pt-px pb-3">
+          <div class="relative">
+            <TextInputV2
+              type="search"
+              appearance="base"
+              class="!w-full self-stretch"
+              value={list.filter()}
+              onInput={(event) => list.onInput(event.currentTarget.value)}
+              placeholder={language.t("dialog.model.search.placeholder")}
+              spellcheck={false}
+              autocorrect="off"
+              autocomplete="off"
+              autocapitalize="off"
+              autofocus
+              aria-label={language.t("dialog.model.search.placeholder")}
+            />
+            <Show when={list.filter()}>
+              <IconButtonV2
+                type="button"
+                variant="ghost-muted"
+                size="small"
+                class="settings-v2-tab-search-clear"
+                icon={<IconV2 name="close" size="large" class="text-v2-icon-icon-muted" />}
+                onClick={() => list.clear()}
+                aria-label={language.t("common.clear")}
+              />
+            </Show>
+          </div>
+        </div>
+        <div data-slot="manage-models-scroll" class="relative min-h-0 flex-1">
+          <div class="settings-v2-panel settings-v2-models h-full px-4 pt-4 pb-4">
+            <Show
+              when={!list.grouped.loading}
+              fallback={
+                <div class="settings-v2-models-status">
+                  {language.t("common.loading")}
+                  {language.t("common.loading.ellipsis")}
+                </div>
+              }
+            >
+              <Show
+                when={list.flat().length > 0}
+                fallback={
+                  <div class="settings-v2-models-status">
+                    <span>{language.t("dialog.model.empty")}</span>
+                    <Show when={list.filter()}>
+                      <span class="settings-v2-models-status-filter">&quot;{list.filter()}&quot;</span>
+                    </Show>
+                  </div>
+                }
+              >
+                <For each={list.grouped.latest}>
+                  {(group) => (
+                    <div class="settings-v2-section" data-component="settings-models-provider">
+                      <div class="settings-v2-models-group-header justify-between">
+                        <div class="flex min-w-0 items-center gap-2">
+                          <ProviderIcon id={group.category} width={16} height={16} class="ml-4 shrink-0" />
+                          <h3 class="settings-v2-section-title">{group.items[0].provider.name}</h3>
+                        </div>
+                        <div>
+                          <SwitchV2
+                            class="mr-6"
+                            checked={providerVisible(group.category)}
+                            onChange={(checked) => setProviderVisibility(group.category, checked)}
+                            hideLabel
+                          >
+                            {group.items[0].provider.name}
+                          </SwitchV2>
+                        </div>
+                      </div>
+                      <SettingsListV2>
+                        <For each={group.items}>
+                          {(item) => (
+                            <SettingsRowV2 title={item.name} description="">
+                              <div>
+                                <SwitchV2
+                                  checked={local.model.visible({ modelID: item.id, providerID: item.provider.id })}
+                                  onChange={(checked) => setModelVisibility(item, checked)}
+                                  hideLabel
+                                >
+                                  {item.name}
+                                </SwitchV2>
+                              </div>
+                            </SettingsRowV2>
+                          )}
+                        </For>
+                      </SettingsListV2>
+                    </div>
+                  )}
+                </For>
+              </Show>
+            </Show>
+          </div>
+        </div>
+      </DialogBody>
+    </DialogV2>
+  )
+}
@@ -1,15 +1,19 @@
 import { Popover as Kobalte } from "@kobalte/core/popover"
-import { Component, ComponentProps, createMemo, JSX, Show, ValidComponent } from "solid-js"
+import { Component, ComponentProps, createMemo, For, JSX, Show, ValidComponent } from "solid-js"
 import { createStore } from "solid-js/store"
 import { useLocal } from "@/context/local"
 import { useDialog } from "@opencode-ai/ui/context/dialog"
 import { popularProviders } from "@/hooks/use-providers"
 import { Button } from "@opencode-ai/ui/button"
 import { IconButton } from "@opencode-ai/ui/icon-button"
+import { ScrollView } from "@opencode-ai/ui/scroll-view"
 import { Tag } from "@opencode-ai/ui/tag"
 import { Dialog } from "@opencode-ai/ui/dialog"
 import { List } from "@opencode-ai/ui/list"
 import { Tooltip } from "@opencode-ai/ui/tooltip"
+import { Icon } from "@opencode-ai/ui/v2/icon"
+import { Tag as TagV2 } from "@opencode-ai/ui/v2/badge-v2"
+import { MenuV2 } from "@opencode-ai/ui/v2/menu-v2"
 import { ModelTooltip } from "./model-tooltip"
 import { useLanguage } from "@/context/language"
 import { decode64 } from "@/utils/base64"
@@ -18,6 +22,22 @@ const isFree = (provider: string, cost: { input: number } | undefined) =>
  provider === "opencode" && (!cost || cost.input === 0)

 type ModelState = ReturnType<typeof useLocal>["model"]
+type ModelItem = ReturnType<ModelState["list"]>[number]
+
+const modelKey = (model: ModelItem) => `${model.provider.id}:${model.id}`
+const manageKey = "action:manage"
+
+const sortModelGroups = (a: { category: string; items: ModelItem[] }, b: { category: string; items: ModelItem[] }) => {
+  const aIndex = popularProviders.indexOf(a.category)
+  const bIndex = popularProviders.indexOf(b.category)
+  const aPopular = aIndex >= 0
+  const bPopular = bIndex >= 0
+
+  if (aPopular && !bPopular) return -1
+  if (!aPopular && bPopular) return 1
+  if (aPopular && bPopular) return aIndex - bIndex
+  return a.items[0].provider.name.localeCompare(b.items[0].provider.name)
+}

 const ModelList: Component<{
  provider?: string
@@ -199,6 +219,271 @@ export function ModelSelectorPopover(props: {
  )
 }

+export function ModelSelectorPopoverV2(props: {
+  provider?: string
+  model?: ModelState
+  children?: JSX.Element
+  triggerAs?: ValidComponent
+  triggerProps?: ModelSelectorTriggerProps
+  onClose?: () => void
+}) {
+  const model = props.model ?? useLocal().model
+  const language = useLanguage()
+  const dialog = useDialog()
+  const [store, setStore] = createStore({ open: false, search: "", active: "" })
+  let searchRef: HTMLInputElement | undefined
+  let contentRef: HTMLDivElement | undefined
+  let restoreTrigger = true
+
+  const allModels = createMemo(() =>
+    model
+      .list()
+      .filter((item) => model.visible({ modelID: item.id, providerID: item.provider.id }))
+      .filter((item) => (props.provider ? item.provider.id === props.provider : true)),
+  )
+  const models = createMemo(() => {
+    const search = store.search.trim().toLowerCase()
+    const filtered = search
+      ? allModels().filter(
+          (item) =>
+            item.name.toLowerCase().includes(search) ||
+            item.id.toLowerCase().includes(search) ||
+            item.provider.name.toLowerCase().includes(search),
+        )
+      : allModels()
+
+    return [...filtered].sort((a, b) => a.name.localeCompare(b.name))
+  })
+  const groups = createMemo(() => {
+    const byProvider = new Map<string, ModelItem[]>()
+    for (const item of models()) {
+      byProvider.set(item.provider.id, [...(byProvider.get(item.provider.id) ?? []), item])
+    }
+    return Array.from(byProvider, ([category, items]) => ({ category, items })).sort(sortModelGroups)
+  })
+  const keys = () => [...models().map(modelKey), manageKey]
+  const current = () => {
+    const value = model.current()
+    return value ? `${value.provider.id}:${value.id}` : undefined
+  }
+  const initialActive = () => {
+    const selected = current()
+    const options = keys()
+    if (selected && options.includes(selected)) return selected
+    return options[0] ?? ""
+  }
+  const activeItem = () =>
+    store.active ? contentRef?.querySelector<HTMLElement>(`[data-option-key="${CSS.escape(store.active)}"]`) : undefined
+  const afterClose = (callback: () => void) => {
+    const complete = () => {
+      if (contentRef?.isConnected) {
+        requestAnimationFrame(complete)
+        return
+      }
+      requestAnimationFrame(() => requestAnimationFrame(callback))
+    }
+    requestAnimationFrame(complete)
+  }
+  const setOpen = (open: boolean) => {
+    if (open) {
+      restoreTrigger = true
+      setStore({ open: true, active: initialActive() })
+      setTimeout(() =>
+        requestAnimationFrame(() => {
+          searchRef?.focus()
+          activeItem()?.scrollIntoView({ block: "nearest" })
+        }),
+      )
+      return
+    }
+    setStore({ open: false, search: "", active: "" })
+  }
+  const select = (item: ModelItem) => {
+    model.set({ modelID: item.id, providerID: item.provider.id }, { recent: true })
+    props.onClose?.()
+  }
+  const selectModel = (item: ModelItem) => {
+    restoreTrigger = false
+    setOpen(false)
+    afterClose(() => select(item))
+  }
+  const manage = () => {
+    restoreTrigger = false
+    setOpen(false)
+    afterClose(() => {
+      void import("./dialog-manage-models").then((x) => {
+        dialog.show(() => <x.DialogManageModelsV2 />)
+      })
+    })
+  }
+  const selectActive = () => {
+    const item = models().find((item) => modelKey(item) === store.active)
+    if (item) {
+      selectModel(item)
+      return
+    }
+    if (store.active === manageKey) manage()
+  }
+  const moveActive = (delta: number) => {
+    const options = keys()
+    if (options.length === 0) return
+    const index = options.indexOf(store.active)
+    const start = index === -1 ? 0 : index
+    setStore("active", options[(start + delta + options.length) % options.length])
+    queueMicrotask(() => activeItem()?.scrollIntoView({ block: "nearest" }))
+  }
+  const setSearch = (value: string) => {
+    const search = value.trim().toLowerCase()
+    const first = [...allModels()]
+      .sort((a, b) => a.name.localeCompare(b.name))
+      .find(
+        (item) =>
+          !search ||
+          item.name.toLowerCase().includes(search) ||
+          item.id.toLowerCase().includes(search) ||
+          item.provider.name.toLowerCase().includes(search),
+      )
+    setStore({ search: value, active: first ? modelKey(first) : manageKey })
+  }
+
+  return (
+    <MenuV2 open={store.open} modal={false} placement="top-start" gutter={6} onOpenChange={setOpen}>
+      <MenuV2.Trigger as={props.triggerAs ?? "div"} {...props.triggerProps}>
+        {props.children}
+      </MenuV2.Trigger>
+      <MenuV2.Portal>
+        <MenuV2.Content
+          ref={(el: HTMLDivElement) => (contentRef = el)}
+          class="w-[284px] overflow-hidden rounded-md border-0 bg-v2-background-bg-layer-01 !p-0 shadow-[var(--v2-elevation-floating)] focus:outline-none"
+          onPointerDownOutside={() => (restoreTrigger = false)}
+          onFocusOutside={() => (restoreTrigger = false)}
+          onCloseAutoFocus={(event) => {
+            if (!restoreTrigger) event.preventDefault()
+          }}
+        >
+          <div class="flex flex-col p-0.5">
+            <div class="flex h-7 items-center gap-2 rounded-sm pl-3 pr-2.5 text-v2-icon-icon-muted">
+              <Icon name="magnifying-glass" size="small" class="shrink-0" />
+              <input
+                ref={(el) => (searchRef = el)}
+                value={store.search}
+                placeholder={language.t("dialog.model.search.placeholder")}
+                class="h-7 min-w-0 flex-1 border-0 bg-transparent text-[13px] font-[440] leading-5 tracking-[-0.04px] text-v2-text-text-base outline-none placeholder:text-v2-text-text-faint"
+                spellcheck={false}
+                autocorrect="off"
+                autocomplete="off"
+                autocapitalize="off"
+                onInput={(event) => setSearch(event.currentTarget.value)}
+                onKeyDown={(event) => {
+                  if (event.key === "Tab") return
+                  event.stopPropagation()
+                  if (event.key === "Escape") {
+                    event.preventDefault()
+                    restoreTrigger = false
+                    setOpen(false)
+                    afterClose(() => props.onClose?.())
+                    return
+                  }
+                  if (event.altKey || event.metaKey) return
+                  if (event.key === "ArrowDown") {
+                    event.preventDefault()
+                    moveActive(1)
+                    return
+                  }
+                  if (event.key === "ArrowUp") {
+                    event.preventDefault()
+                    moveActive(-1)
+                    return
+                  }
+                  if (event.key === "Enter" && !event.isComposing) {
+                    event.preventDefault()
+                    selectActive()
+                  }
+                }}
+              />
+              <Show when={store.search.trim()}>
+                <button
+                  type="button"
+                  class="flex size-5 items-center justify-center rounded-sm text-v2-icon-icon-muted hover:bg-v2-overlay-simple-overlay-hover"
+                  onPointerDown={(event) => event.preventDefault()}
+                  onClick={() => setSearch("")}
+                  aria-label={language.t("common.clear")}
+                >
+                  <Icon name="close" size="small" />
+                </button>
+              </Show>
+            </div>
+          </div>
+          <div class="h-px bg-v2-border-border-muted" />
+          <ScrollView data-slot="model-selector-scroll" class="max-h-[220px] min-h-0">
+            <div class="flex flex-col p-0.5 pt-0">
+              <Show
+                when={models().length > 0}
+                fallback={
+                  <div class="flex h-12 items-center px-3 text-[13px] font-[440] leading-5 tracking-[-0.04px] text-v2-text-text-faint">
+                    {language.t("dialog.model.empty")}
+                  </div>
+                }
+              >
+                <For each={groups()}>
+                  {(group) => (
+                    <MenuV2.Group>
+                      <MenuV2.GroupLabel class="gap-2 px-3">
+                        <span class="min-w-0 truncate">{group.items[0].provider.name}</span>
+                      </MenuV2.GroupLabel>
+                      <MenuV2.RadioGroup value={current()}>
+                        <For each={group.items}>
+                          {(item) => (
+                            <MenuV2.RadioItem
+                              value={modelKey(item)}
+                              data-option-key={modelKey(item)}
+                              data-selected-model={current() === modelKey(item) ? true : undefined}
+                              class="scroll-my-6"
+                              classList={{ "!bg-v2-overlay-simple-overlay-hover": store.active === modelKey(item) }}
+                              onMouseEnter={() => {
+                                setStore("active", modelKey(item))
+                                setTimeout(() => searchRef?.focus())
+                              }}
+                              onSelect={() => selectModel(item)}
+                            >
+                              <span class="min-w-0 truncate">{item.name}</span>
+                              <Show when={isFree(item.provider.id, item.cost)}>
+                                <TagV2 class="shrink-0">{language.t("model.tag.free")}</TagV2>
+                              </Show>
+                              <Show when={item.latest}>
+                                <TagV2 class="shrink-0">{language.t("model.tag.latest")}</TagV2>
+                              </Show>
+                            </MenuV2.RadioItem>
+                          )}
+                        </For>
+                      </MenuV2.RadioGroup>
+                    </MenuV2.Group>
+                  )}
+                </For>
+              </Show>
+            </div>
+          </ScrollView>
+          <div class="h-px bg-v2-border-border-muted" />
+          <div class="flex flex-col p-0.5">
+            <MenuV2.Item
+              data-option-key={manageKey}
+              classList={{ "!bg-v2-overlay-simple-overlay-hover": store.active === manageKey }}
+              onMouseEnter={() => {
+                setStore("active", manageKey)
+                setTimeout(() => searchRef?.focus())
+              }}
+              onSelect={manage}
+            >
+              <Icon name="outline-sliders" size="small" />
+              <span class="min-w-0 flex-1 truncate leading-5">{language.t("dialog.model.manage")}</span>
+            </MenuV2.Item>
+          </div>
+        </MenuV2.Content>
+      </MenuV2.Portal>
+    </MenuV2>
+  )
+}
+
 export const DialogSelectModel: Component<{ provider?: string; model?: ModelState }> = (props) => {
  const dialog = useDialog()
  const language = useLanguage()
@@ -35,10 +35,14 @@ import { DockShellForm, DockTray } from "@opencode-ai/ui/dock-surface"
 import { Icon } from "@opencode-ai/ui/icon"
 import { ProviderIcon } from "@opencode-ai/ui/provider-icon"
 import { Tooltip, TooltipKeybind } from "@opencode-ai/ui/tooltip"
+import { ButtonV2 } from "@opencode-ai/ui/v2/button-v2"
+import { KeybindV2 } from "@opencode-ai/ui/v2/keybind-v2"
+import { MenuV2 } from "@opencode-ai/ui/v2/menu-v2"
+import { TooltipV2 } from "@opencode-ai/ui/v2/tooltip-v2"
 import { IconButton } from "@opencode-ai/ui/icon-button"
 import { Select } from "@opencode-ai/ui/select"
 import { useDialog } from "@opencode-ai/ui/context/dialog"
-import { ModelSelectorPopover } from "@/components/dialog-select-model"
+import { ModelSelectorPopover, ModelSelectorPopoverV2 } from "@/components/dialog-select-model"
 import { useCommand } from "@/context/command"
 import { Persist, persisted } from "@/utils/persist"
 import { usePermission } from "@/context/permission"
@@ -66,6 +70,7 @@ import { promptPlaceholder } from "./prompt-input/placeholder"
 import { createPromptInputTransientState } from "./prompt-input/transient-state"
 import { showToast } from "@/utils/toast"
 import { ImagePreview } from "@opencode-ai/ui/image-preview"
+import type { ReferenceInfo } from "@opencode-ai/sdk/v2/client"

 export type PromptInputState = ReturnType<typeof usePrompt>

@@ -212,6 +217,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
  let fileInputRef: HTMLInputElement | undefined
  let scrollRef!: HTMLDivElement
  let slashPopoverRef!: HTMLDivElement
+  let restoreEndOnFocus = true

  const mirror = { input: false }
  const inset = 56
@@ -591,6 +597,16 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
    })
  }

+  const handleFocus = () => {
+    if (!restoreEndOnFocus) return
+    restoreEndOnFocus = false
+    requestAnimationFrame(() => {
+      if (document.activeElement !== editorRef) return
+      setCursorPosition(editorRef, prompt.cursor() ?? promptLength(prompt.current()))
+      queueScroll()
+    })
+  }
+
  const renderEditorWithCursor = (parts: Prompt) => {
    const cursor = currentCursor()
    renderEditor(parts)
@@ -627,24 +643,89 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
    })
  }

+  const referenceDescription = (reference: ReferenceInfo) =>
+    reference.source.type === "git" ? reference.source.repository : reference.source.path
+
+  const referenceList = createMemo(() =>
+    sync()
+      .data.reference.filter((reference) => !reference.hidden)
+      .map(
+        (reference): AtOption => ({
+          type: "reference",
+          name: reference.name,
+          path: reference.path,
+          display: reference.name,
+          description: reference.description ?? referenceDescription(reference),
+        }),
+      ),
+  )
+
  const agentList = createMemo(() =>
    props.controls.agents.available
      .filter((agent) => !agent.hidden && agent.mode !== "primary")
      .map((agent): AtOption => ({ type: "agent", name: agent.name, display: agent.name })),
  )

+  const mcpResourceList = createMemo(() =>
+    Object.values(sync().data.mcp_resource).map(
+      (resource): AtOption => ({
+        type: "resource",
+        name: resource.name,
+        uri: resource.uri,
+        client: resource.client,
+        display: resource.name,
+        description: resource.description,
+        mime: resource.mimeType,
+      }),
+    ),
+  )
+
  const handleAtSelect = (option: AtOption | undefined) => {
    if (!option) return
    if (option.type === "agent") {
      addPart({ type: "agent", name: option.name, content: "@" + option.name, start: 0, end: 0 })
-    } else {
-      addPart({ type: "file", path: option.path, content: "@" + option.path, start: 0, end: 0 })
+      return
    }
+    if (option.type === "reference") {
+      addPart({
+        type: "file",
+        path: option.path,
+        content: "@" + option.name,
+        start: 0,
+        end: 0,
+        mime: "application/x-directory",
+        filename: option.name,
+      })
+      return
+    }
+    if (option.type === "resource") {
+      addPart({
+        type: "file",
+        path: option.uri,
+        content: "@" + option.name,
+        start: 0,
+        end: 0,
+        mime: option.mime ?? "text/plain",
+        filename: option.name,
+        url: option.uri,
+        source: {
+          type: "resource",
+          text: { value: "@" + option.name, start: 0, end: 0 },
+          clientName: option.client,
+          uri: option.uri,
+        },
+      })
+      return
+    }
+    addPart({ type: "file", path: option.path, content: "@" + option.path, start: 0, end: 0 })
  }

  const atKey = (x: AtOption | undefined) => {
    if (!x) return ""
-    return x.type === "agent" ? `agent:${x.name}` : `file:${x.path}`
+    if (x.type === "agent") return `agent:${x.name}`
+    if (x.type === "reference") return `reference:${x.name}`
+    if (x.type === "resource") return `resource:${x.client}:${x.uri}`
+    return `file:${x.path}`
  }

  const {
@@ -655,30 +736,36 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
    onKeyDown: atOnKeyDown,
  } = useFilteredList<AtOption>({
    items: async (query) => {
+      const references = referenceList()
      const agents = agentList()
+      const mcpResources = mcpResourceList()
      const open = recent()
      const seen = new Set(open)
      const pinned: AtOption[] = open.map((path) => ({ type: "file", path, display: path, recent: true }))
-      if (!query.trim()) return [...agents, ...pinned]
+      if (!query.trim()) return [...references, ...agents, ...mcpResources, ...pinned]
      const paths = await files.searchFilesAndDirectories(query)
      const fileOptions: AtOption[] = paths
        .filter((path) => !seen.has(path))
        .map((path) => ({ type: "file", path, display: path }))
-      return [...agents, ...pinned, ...fileOptions]
+      return [...references, ...agents, ...mcpResources, ...pinned, ...fileOptions]
    },
    key: atKey,
    filterKeys: ["display"],
    skipFilter: (item) => item.type === "file" && !item.recent,
    groupBy: (item) => {
+      if (item.type === "reference") return "reference"
      if (item.type === "agent") return "agent"
+      if (item.type === "resource") return "resource"
      if (item.recent) return "recent"
      return "file"
    },
    sortGroupsBy: (a, b) => {
      const rank = (category: string) => {
-        if (category === "agent") return 0
-        if (category === "recent") return 1
-        return 2
+        if (category === "reference") return 0
+        if (category === "agent") return 1
+        if (category === "resource") return 2
+        if (category === "recent") return 3
+        return 4
      }
      return rank(a.category) - rank(b.category)
    },
@@ -744,7 +831,17 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
    const pill = document.createElement("span")
    pill.textContent = part.content
    pill.setAttribute("data-type", part.type)
-    if (part.type === "file") pill.setAttribute("data-path", part.path)
+    if (part.type === "file") {
+      pill.setAttribute("data-path", part.path)
+      if (part.mime) pill.setAttribute("data-mime", part.mime)
+      if (part.filename) pill.setAttribute("data-filename", part.filename)
+      if (part.url) pill.setAttribute("data-url", part.url)
+      if (part.source?.type === "resource") {
+        pill.setAttribute("data-source-type", part.source.type)
+        pill.setAttribute("data-source-client-name", part.source.clientName)
+        pill.setAttribute("data-source-uri", part.source.uri)
+      }
+    }
    if (part.type === "agent") pill.setAttribute("data-name", part.name)
    pill.setAttribute("contenteditable", "false")
    pill.style.userSelect = "text"
@@ -789,8 +886,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
    }
  }

-  // Auto-scroll active command into view when navigating with keyboard
-  createEffect(() => {
+  const scrollSlashActiveIntoView = () => {
    const activeId = slashActive()
    if (!activeId || !slashPopoverRef) return

@@ -798,7 +894,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
      const element = slashPopoverRef.querySelector(`[data-slash-id="${activeId}"]`)
      element?.scrollIntoView({ block: "nearest", behavior: "smooth" })
    })
-  })
+  }
  const selectPopoverActive = () => {
    if (store.popover === "at") {
      const items = atFlat()
@@ -860,12 +956,29 @@ export const PromptInput: Component<PromptInputProps> = (props) => {

    const pushFile = (file: HTMLElement) => {
      const content = file.textContent ?? ""
+      const source =
+        file.dataset.sourceType === "resource" && file.dataset.sourceClientName && file.dataset.sourceUri
+          ? {
+              type: "resource" as const,
+              text: {
+                value: content,
+                start: position,
+                end: position + content.length,
+              },
+              clientName: file.dataset.sourceClientName,
+              uri: file.dataset.sourceUri,
+            }
+          : undefined
      parts.push({
        type: "file",
        path: file.dataset.path!,
        content,
        start: position,
        end: position + content.length,
+        ...(file.dataset.mime ? { mime: file.dataset.mime } : {}),
+        ...(file.dataset.filename ? { filename: file.dataset.filename } : {}),
+        ...(file.dataset.url ? { url: file.dataset.url } : {}),
+        ...(source ? { source } : {}),
      })
      position += content.length
    }
@@ -1285,6 +1398,9 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
        }
        if (store.popover === "slash") {
          slashOnKeyDown(event)
+          if (event.key === "ArrowUp" || event.key === "ArrowDown" || ctrlNav) {
+            scrollSlashActiveIntoView()
+          }
        }
        event.preventDefault()
        return
@@ -1343,9 +1459,9 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
  }

  const agentsLoading = () => props.controls.agents.loading
-  const agentsShouldFadeIn = createMemo((prev) => prev ?? agentsLoading())
+  const agentsShouldFadeIn = createMemo<boolean>((prev) => prev ?? agentsLoading())
  const providersLoading = () => props.controls.model.loading
-  const providersShouldFadeIn = createMemo((prev) => prev ?? providersLoading())
+  const providersShouldFadeIn = createMemo<boolean>((prev) => prev ?? providersLoading())

  const [promptReady] = createResource(
    () => prompt.ready.promise,
@@ -1359,12 +1475,14 @@ export const PromptInput: Component<PromptInputProps> = (props) => {

  const modelControlState = createMemo<ComposerModelControlState>(() => ({
    loading: providersLoading(),
+    shouldAnimate: providersShouldFadeIn(),
    paid: props.controls.model.paid,
    title: language.t("command.model.choose"),
-    keybind: command.keybind("model.choose"),
+    keybind: command.keybindParts("model.choose"),
    model: props.controls.model.selection,
    providerID: props.controls.model.selection.current()?.provider?.id,
    modelName: props.controls.model.selection.current()?.name ?? language.t("dialog.model.select.title"),
+    newLayoutDesigns: props.controls.newLayoutDesigns,
    style: control(),
    onClose: restoreFocus,
    onUnpaidClick: () => {
@@ -1375,10 +1493,15 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
  }))

  const newSession = () => props.variant === "new-session"
+  const bindEditorRef = (el: HTMLDivElement) => {
+    editorRef = el
+    restoreEndOnFocus = true
+    props.ref?.(el)
+  }
  const showAgentControl = createMemo(() => props.controls.agents.visible && props.controls.agents.options.length > 0)
  const agentControlState = createMemo<ComposerAgentControlState>(() => ({
    title: language.t("command.agent.cycle"),
-    keybind: command.keybind("agent.cycle"),
+    keybind: command.keybindParts("agent.cycle"),
    options: props.controls.agents.options,
    current: props.controls.agents.current,
    style: control(),
@@ -1403,6 +1526,8 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
        setSlashActive={setSlashActive}
        onSlashSelect={handleSlashSelect}
        commandKeybind={command.keybind}
+        commandKeybindParts={command.keybindParts}
+        newLayoutDesigns={props.controls.newLayoutDesigns}
        t={(key) => language.t(key as Parameters<typeof language.t>[0])}
      />
      <Switch>
@@ -1456,10 +1581,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                <div class="relative max-h-[180px] overflow-y-auto no-scrollbar" ref={(el) => (scrollRef = el)}>
                  <div
                    data-component="prompt-input"
-                    ref={(el) => {
-                      editorRef = el
-                      props.ref?.(el)
-                    }}
+                    ref={bindEditorRef}
                    role="textbox"
                    aria-multiline="true"
                    aria-label={designPlaceholder()}
@@ -1474,6 +1596,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                    onPaste={handlePaste}
                    onCompositionStart={handleCompositionStart}
                    onCompositionEnd={handleCompositionEnd}
+                    onFocus={handleFocus}
                    onBlur={handleBlur}
                    onKeyDown={handleKeyDown}
                    classList={{
@@ -1494,12 +1617,16 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                </div>
              </div>
              <div class="flex h-11 items-center px-2">
-                <div class="flex min-w-0 flex-1 items-center gap-0">
+                <div class="flex min-w-0 flex-1 items-center gap-1">
                  {fileAttachmentInput()}
-                  <TooltipKeybind
+                  <TooltipV2
                    placement="top"
-                    title={language.t("prompt.action.attachFile")}
-                    keybind={command.keybind("file.attach")}
+                    value={
+                      <>
+                        {language.t("prompt.action.attachFile")}
+                        <KeybindV2 keys={command.keybindParts("file.attach")} variant="neutral" />
+                      </>
+                    }
                  >
                    <IconButton
                      data-action="prompt-attach"
@@ -1513,47 +1640,76 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                      tabIndex={store.mode === "normal" ? undefined : -1}
                      aria-label={language.t("prompt.action.attachFile")}
                    />
-                  </TooltipKeybind>
+                  </TooltipV2>
                  <Show when={showAgentControl()}>
                    <ComposerAgentControl state={agentControlState()} />
                  </Show>
                  {props.toolbar}
                  <ComposerModelControl state={modelControlState()} />
-                  <Show when={store.mode !== "shell" && showVariantControl()}>
+                  <Show when={!providersLoading() && store.mode !== "shell" && showVariantControl()}>
                    <div
                      data-component="prompt-variant-control"
+                      class="[&_[data-action=prompt-model-variant]]:![font-weight:440]"
                      classList={{
+                        "animate-in fade-in": providersShouldFadeIn(),
                        "hidden group-hover/prompt-input:block group-focus-within/prompt-input:block":
                          !props.controls.model.selection.variant.current() && !store.variantOpen,
                      }}
                    >
-                      <TooltipKeybind
+                      <TooltipV2
                        placement="top"
                        gutter={4}
-                        title={language.t("command.model.variant.cycle")}
-                        keybind={command.keybind("model.variant.cycle")}
+                        value={
+                          <>
+                            {language.t("command.model.variant.cycle")}
+                            <KeybindV2 keys={command.keybindParts("model.variant.cycle")} variant="neutral" />
+                          </>
+                        }
                      >
-                        <Select
-                          size="normal"
-                          options={variants()}
-                          current={props.controls.model.selection.variant.current() ?? "default"}
-                          label={(x) => (x === "default" ? language.t("common.default") : x)}
+                        <MenuV2
+                          gutter={6}
+                          modal={false}
+                          placement="top-start"
                          onOpenChange={(open) => setStore("variantOpen", open)}
-                          onSelect={(value) => {
-                            props.controls.model.selection.variant.set(value === "default" ? undefined : value)
-                            restoreFocus()
-                          }}
-                          class="capitalize max-w-[160px] justify-start text-v2-text-text-faint"
-                          valueClass="truncate text-[13px] font-[440] leading-5 text-v2-text-text-faint"
-                          triggerStyle={control()}
-                          triggerProps={{ "data-action": "prompt-model-variant" }}
-                          variant="ghost"
-                        />
-                      </TooltipKeybind>
+                        >
+                          <MenuV2.Trigger
+                            as={ButtonV2}
+                            data-action="prompt-model-variant"
+                            variant="ghost-muted"
+                            size="normal"
+                            class="max-w-[160px] justify-start capitalize"
+                            style={control()}
+                          >
+                            <span class="truncate">
+                              {props.controls.model.selection.variant.current() ?? language.t("common.default")}
+                            </span>
+                            <span class="-ml-0.5 -mr-1 flex shrink-0">
+                              <Icon name="chevron-down" size="small" />
+                            </span>
+                          </MenuV2.Trigger>
+                          <MenuV2.Portal>
+                            <MenuV2.Content>
+                              <MenuV2.RadioGroup
+                                value={props.controls.model.selection.variant.current() ?? "default"}
+                                onChange={(value) => {
+                                  props.controls.model.selection.variant.set(value === "default" ? undefined : value)
+                                  restoreFocus()
+                                }}
+                              >
+                                {variants().map((value) => (
+                                  <MenuV2.RadioItem value={value} class="capitalize">
+                                    {value === "default" ? language.t("common.default") : value}
+                                  </MenuV2.RadioItem>
+                                ))}
+                              </MenuV2.RadioGroup>
+                            </MenuV2.Content>
+                          </MenuV2.Portal>
+                        </MenuV2>
+                      </TooltipV2>
                    </div>
                  </Show>
                </div>
-                <Tooltip placement="top" inactive={!working() && blank()} value={tip()}>
+                <TooltipV2 placement="top" inactive={!working() && blank()} value={tip()}>
                  <IconButton
                    data-action="prompt-submit"
                    type="submit"
@@ -1568,7 +1724,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                    }}
                    aria-label={stopping() ? language.t("prompt.action.stop") : language.t("prompt.action.send")}
                  />
-                </Tooltip>
+                </TooltipV2>
              </div>
            </DockShellForm>
          </div>
@@ -1628,10 +1784,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
              >
                <div
                  data-component="prompt-input"
-                  ref={(el) => {
-                    editorRef = el
-                    props.ref?.(el)
-                  }}
+                  ref={bindEditorRef}
                  role="textbox"
                  aria-multiline="true"
                  aria-label={placeholder()}
@@ -1646,6 +1799,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                  onPaste={handlePaste}
                  onCompositionStart={handleCompositionStart}
                  onCompositionEnd={handleCompositionEnd}
+                  onFocus={handleFocus}
                  onBlur={handleBlur}
                  onKeyDown={handleKeyDown}
                  classList={{
@@ -1765,7 +1919,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                    <Show when={!agentsLoading()}>
                      <div
                        data-component="prompt-agent-control"
-                        style={agentsShouldFadeIn() ? { animation: "fade-in 0.3s" } : undefined}
+                        classList={{ "animate-in fade-in duration-300": agentsShouldFadeIn() }}
                      >
                        <TooltipKeybind
                          placement="top"
@@ -1794,7 +1948,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                      <Show when={store.mode !== "shell"}>
                        <div
                          data-component="prompt-model-control"
-                          style={providersShouldFadeIn() ? { animation: "fade-in 0.3s" } : undefined}
+                          classList={{ "animate-in fade-in duration-300": providersShouldFadeIn() }}
                        >
                          <Show
                            when={props.controls.model.paid}
@@ -1873,7 +2027,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {
                        <Show when={showVariantControl()}>
                          <div
                            data-component="prompt-variant-control"
-                            style={providersShouldFadeIn() ? { animation: "fade-in 0.3s" } : undefined}
+                            classList={{ "animate-in fade-in duration-300": providersShouldFadeIn() }}
                          >
                            <TooltipKeybind
                              placement="top"
@@ -1914,7 +2068,7 @@ export const PromptInput: Component<PromptInputProps> = (props) => {

 type ComposerAgentControlState = {
  title: string
-  keybind: string
+  keybind: string[]
  options: string[]
  current: string
  style: JSX.CSSProperties | undefined
@@ -1923,12 +2077,14 @@ type ComposerAgentControlState = {

 type ComposerModelControlState = {
  loading: boolean
+  shouldAnimate: boolean
  paid: boolean
  title: string
-  keybind: string
+  keybind: string[]
  model: ReturnType<typeof useLocal>["model"]
  providerID?: string
  modelName: string
+  newLayoutDesigns: boolean
  style: JSX.CSSProperties | undefined
  onClose: () => void
  onUnpaidClick: () => void
@@ -1940,7 +2096,16 @@ function ComposerAgentControl(props: { state: ComposerAgentControlState }) {
      <div class="pointer-events-none absolute left-2 top-1/2 z-10 flex size-4 -translate-y-1/2 items-center justify-center text-v2-icon-icon-muted">
        <Icon name="sliders" size="small" />
      </div>
-      <TooltipKeybind placement="top" gutter={4} title={props.state.title} keybind={props.state.keybind}>
+      <TooltipV2
+        placement="top"
+        gutter={4}
+        value={
+          <>
+            {props.state.title}
+            <KeybindV2 keys={props.state.keybind} variant="neutral" />
+          </>
+        }
+      >
        <Select
          size="normal"
          options={props.state.options}
@@ -1952,7 +2117,7 @@ function ComposerAgentControl(props: { state: ComposerAgentControlState }) {
          triggerProps={{ "data-action": "prompt-agent" }}
          variant="ghost"
        />
-      </TooltipKeybind>
+      </TooltipV2>
    </div>
  )
 }
@@ -1963,13 +2128,23 @@ function ComposerModelControl(props: { state: ComposerModelControlState }) {
      <Show
        when={props.state.paid}
        fallback={
-          <TooltipKeybind placement="top" gutter={4} title={props.state.title} keybind={props.state.keybind}>
+          <TooltipV2
+            placement="top"
+            gutter={4}
+            value={
+              <>
+                {props.state.title}
+                <KeybindV2 keys={props.state.keybind} variant="neutral" />
+              </>
+            }
+          >
            <Button
              data-action="prompt-model"
              as="div"
              variant="ghost"
              size="normal"
              class="min-w-0 max-w-[220px] justify-start text-[13px] font-[440] leading-5 text-v2-text-text-faint group"
+              classList={{ "animate-in fade-in": props.state.shouldAnimate }}
              style={props.state.style}
              onClick={props.state.onUnpaidClick}
            >
@@ -1987,39 +2162,78 @@ function ComposerModelControl(props: { state: ComposerModelControlState }) {
                <Icon name="chevron-down" size="small" class="text-v2-icon-icon-muted" />
              </span>
            </Button>
-          </TooltipKeybind>
+          </TooltipV2>
        }
      >
-        <TooltipKeybind placement="top" gutter={4} title={props.state.title} keybind={props.state.keybind}>
-          <ModelSelectorPopover
-            model={props.state.model}
-            triggerAs={Button}
-            triggerProps={{
-              variant: "ghost",
-              size: "normal",
-              style: props.state.style,
-              class:
-                "min-w-0 max-w-[220px] justify-start text-[13px] font-[440] leading-5 text-v2-text-text-faint group",
-              "data-action": "prompt-model",
-            }}
-            onClose={props.state.onClose}
+        <TooltipV2
+          placement="top"
+          gutter={4}
+          value={
+            <>
+              {props.state.title}
+              <KeybindV2 keys={props.state.keybind} variant="neutral" />
+            </>
+          }
+        >
+          <Show
+            when={props.state.newLayoutDesigns}
+            fallback={
+              <ModelSelectorPopover
+                model={props.state.model}
+                triggerAs={Button}
+                triggerProps={{
+                  variant: "ghost",
+                  size: "normal",
+                  style: props.state.style,
+                  class:
+                    "min-w-0 max-w-[220px] justify-start text-[13px] font-[440] leading-5 text-v2-text-text-faint group",
+                  classList: { "animate-in fade-in": props.state.shouldAnimate },
+                  "data-action": "prompt-model",
+                }}
+                onClose={props.state.onClose}
+              >
+                <ModelControlContent state={props.state} />
+              </ModelSelectorPopover>
+            }
          >
-            <Show when={props.state.providerID}>
-              {(providerID) => (
-                <ProviderIcon
-                  id={providerID()}
-                  class="size-4 shrink-0 opacity-40 group-hover:opacity-100 transition-opacity duration-150"
-                  style={{ "will-change": "opacity", transform: "translateZ(0)" }}
-                />
-              )}
-            </Show>
-            <span class="truncate">{props.state.modelName}</span>
-            <span class="-ml-1 shrink-0 flex size-fit">
-              <Icon name="chevron-down" size="small" class="text-v2-icon-icon-muted" />
-            </span>
-          </ModelSelectorPopover>
-        </TooltipKeybind>
+            <ModelSelectorPopoverV2
+              model={props.state.model}
+              triggerAs={ButtonV2}
+              triggerProps={{
+                variant: "ghost-muted",
+                size: "normal",
+                style: props.state.style,
+                class: "min-w-0 max-w-[220px] justify-start ![font-weight:440] group",
+                classList: { "animate-in fade-in": props.state.shouldAnimate },
+                "data-action": "prompt-model",
+              }}
+              onClose={props.state.onClose}
+            >
+              <ModelControlContent state={props.state} v2 />
+            </ModelSelectorPopoverV2>
+          </Show>
+        </TooltipV2>
      </Show>
    </Show>
  )
 }
+
+function ModelControlContent(props: { state: ComposerModelControlState; v2?: boolean }) {
+  return (
+    <>
+      <Show when={props.state.providerID}>
+        {(providerID) => (
+          <ProviderIcon
+            id={providerID()}
+            class="size-4 shrink-0 opacity-40 group-hover:opacity-100 transition-opacity duration-150"
+            style={{ "will-change": "opacity", transform: "translateZ(0)" }}
+          />
+        )}
+      </Show>
+      <span class="truncate">{props.state.modelName}</span>
+      <span class={props.v2 ? "-ml-0.5 -mr-1 flex shrink-0" : "-ml-1 shrink-0 flex size-fit"}>
+        <Icon name="chevron-down" size="small" class="text-v2-icon-icon-muted" />
+      </span>
+    </>
+  )
+}
@@ -100,6 +100,41 @@ describe("buildRequestParts", () => {
    )
  })

+  test("preserves reference aliases as directory file parts", () => {
+    const result = buildRequestParts({
+      prompt: [
+        {
+          type: "file",
+          path: "/repo/../docs",
+          content: "@docs",
+          start: 0,
+          end: 5,
+          mime: "application/x-directory",
+          filename: "docs",
+        },
+      ],
+      context: [],
+      images: [],
+      text: "@docs",
+      messageID: "msg_reference",
+      sessionID: "ses_reference",
+      sessionDirectory: "/repo/app",
+    })
+
+    const filePart = result.requestParts.find((part) => part.type === "file")
+    expect(filePart).toBeDefined()
+    if (filePart?.type === "file") {
+      expect(filePart.mime).toBe("application/x-directory")
+      expect(filePart.filename).toBe("docs")
+      expect(filePart.url).toBe("file:///repo/../docs")
+      expect(filePart.source?.type).toBe("file")
+      if (filePart.source?.type === "file") {
+        expect(filePart.source.path).toBe("/repo/../docs")
+        expect(filePart.source.text.value).toBe("@docs")
+      }
+    }
+  })
+
  test("deduplicates context files when prompt already includes same path", () => {
    const prompt: Prompt = [{ type: "file", path: "src/foo.ts", content: "@src/foo.ts", start: 0, end: 11 }]

@@ -99,21 +99,31 @@ export function buildRequestParts(input: BuildRequestPartsInput) {

  const files = input.prompt.filter(isFileAttachment).map((attachment) => {
    const path = absolute(input.sessionDirectory, attachment.path)
+    const source = attachment.source
+      ? {
+          ...attachment.source,
+          text: {
+            value: attachment.content,
+            start: attachment.start,
+            end: attachment.end,
+          },
+        }
+      : {
+          type: "file" as const,
+          text: {
+            value: attachment.content,
+            start: attachment.start,
+            end: attachment.end,
+          },
+          path,
+        }
    return {
      id: Identifier.ascending("part"),
      type: "file",
-      mime: "text/plain",
-      url: `file://${encodeFilePath(path)}${fileQuery(attachment.selection)}`,
-      filename: getFilename(attachment.path),
-      source: {
-        type: "file",
-        text: {
-          value: attachment.content,
-          start: attachment.start,
-          end: attachment.end,
-        },
-        path,
-      },
+      mime: attachment.mime ?? "text/plain",
+      url: attachment.url ?? `file://${encodeFilePath(path)}${fileQuery(attachment.selection)}`,
+      filename: attachment.filename ?? getFilename(attachment.path),
+      source,
    } satisfies PromptRequestPart
  })

@@ -37,7 +37,7 @@ export const PromptContextItems: Component<ContextItemsProps> = (props) => {
                  </span>
                }
                placement="top"
-                openDelay={2000}
+                openDelay={800}
              >
                <div
                  classList={{
@@ -1,10 +1,22 @@
 import { Component, For, Match, Show, Switch } from "solid-js"
 import { FileIcon } from "@opencode-ai/ui/file-icon"
 import { Icon } from "@opencode-ai/ui/icon"
+import { Tag } from "@opencode-ai/ui/v2/badge-v2"
+import { KeybindV2 } from "@opencode-ai/ui/v2/keybind-v2"
 import { getDirectory, getFilename } from "@opencode-ai/core/util/path"

 export type AtOption =
  | { type: "agent"; name: string; display: string }
+  | {
+      type: "resource"
+      name: string
+      uri: string
+      client: string
+      display: string
+      description?: string
+      mime?: string
+    }
+  | { type: "reference"; name: string; path: string; display: string; description: string }
  | { type: "file"; path: string; display: string; recent?: boolean }

 export interface SlashCommand {
@@ -30,6 +42,8 @@ type PromptPopoverProps = {
  setSlashActive: (id: string) => void
  onSlashSelect: (item: SlashCommand) => void
  commandKeybind: (id: string) => string | undefined
+  commandKeybindParts: (id: string) => string[]
+  newLayoutDesigns: boolean
  t: (key: string) => string
 }

@@ -41,15 +55,29 @@ export const PromptPopover: Component<PromptPopoverProps> = (props) => {
          if (props.popover === "slash") props.setSlashPopoverRef(el)
        }}
        class="absolute inset-x-0 -top-2 -translate-y-full origin-bottom-left max-h-80 min-h-10
-                 overflow-auto no-scrollbar flex flex-col p-2 rounded-[12px]
-                 bg-surface-raised-stronger-non-alpha shadow-[var(--shadow-lg-border-base)]"
+                 overflow-auto no-scrollbar flex flex-col p-2"
+        classList={{
+          "z-[70] rounded-[10px] bg-v2-background-bg-base shadow-[var(--v2-elevation-raised)]": props.newLayoutDesigns,
+          "rounded-[12px] bg-surface-raised-stronger-non-alpha shadow-[var(--shadow-lg-border-base)]":
+            !props.newLayoutDesigns,
+        }}
        onMouseDown={(e) => e.preventDefault()}
      >
        <Switch>
          <Match when={props.popover === "at"}>
            <Show
              when={props.atFlat.length > 0}
-              fallback={<div class="text-text-weak px-2 py-1">{props.t("prompt.popover.emptyResults")}</div>}
+              fallback={
+                <div
+                  class="px-2 py-1"
+                  classList={{
+                    "text-v2-text-text-muted": props.newLayoutDesigns,
+                    "text-text-weak": !props.newLayoutDesigns,
+                  }}
+                >
+                  {props.t("prompt.popover.emptyResults")}
+                </div>
+              }
            >
              <For each={props.atFlat.slice(0, 10)}>
                {(item) => {
@@ -58,13 +86,117 @@ export const PromptPopover: Component<PromptPopoverProps> = (props) => {
                  if (item.type === "agent") {
                    return (
                      <button
-                        class="w-full flex items-center gap-x-2 rounded-md px-2 py-0.5"
-                        classList={{ "bg-surface-raised-base-hover": props.atActive === key }}
+                        class="w-full flex items-center gap-x-2 px-2 py-0.5"
+                        classList={{
+                          "rounded-[4px]": props.newLayoutDesigns,
+                          "rounded-md": !props.newLayoutDesigns,
+                          "bg-v2-overlay-simple-overlay-hover": props.newLayoutDesigns && props.atActive === key,
+                          "bg-surface-raised-base-hover": !props.newLayoutDesigns && props.atActive === key,
+                        }}
                        onClick={() => props.onAtSelect(item)}
-                        onMouseEnter={() => props.setAtActive(key)}
+                        onPointerMove={() => props.setAtActive(key)}
                      >
                        <Icon name="brain" size="small" class="text-icon-info-active shrink-0" />
-                        <span class="text-14-regular text-text-strong whitespace-nowrap">@{item.name}</span>
+                        <span
+                          class="whitespace-nowrap"
+                          classList={{
+                            "text-[13px] leading-[calc(var(--font-size-base)*1.8)] tracking-[-0.04px] [font-weight:440]":
+                              props.newLayoutDesigns,
+                            "text-v2-text-text-base": props.newLayoutDesigns,
+                            "text-14-regular": !props.newLayoutDesigns,
+                            "text-text-strong": !props.newLayoutDesigns,
+                          }}
+                        >
+                          @{item.name}
+                        </span>
+                      </button>
+                    )
+                  }
+
+                  if (item.type === "resource") {
+                    return (
+                      <button
+                        class="w-full flex items-center gap-x-2 px-2 py-0.5"
+                        classList={{
+                          "rounded-[4px]": props.newLayoutDesigns,
+                          "rounded-md": !props.newLayoutDesigns,
+                          "bg-v2-overlay-simple-overlay-hover": props.newLayoutDesigns && props.atActive === key,
+                          "bg-surface-raised-base-hover": !props.newLayoutDesigns && props.atActive === key,
+                        }}
+                        onClick={() => props.onAtSelect(item)}
+                        onPointerMove={() => props.setAtActive(key)}
+                      >
+                        <FileIcon node={{ path: item.uri, type: "file" }} class="shrink-0 size-4" />
+                        <div
+                          class="flex items-center min-w-0"
+                          classList={{
+                            "text-[13px] leading-[calc(var(--font-size-base)*1.8)] tracking-[-0.04px] [font-weight:440]":
+                              props.newLayoutDesigns,
+                            "text-14-regular": !props.newLayoutDesigns,
+                          }}
+                        >
+                          <span
+                            class="text-text-strong whitespace-nowrap"
+                            classList={{ "text-v2-text-text-base": props.newLayoutDesigns }}
+                          >
+                            @{item.name}
+                          </span>
+                          <Show when={item.description}>
+                            {(description) => (
+                              <span
+                                class="whitespace-nowrap truncate min-w-0 ml-2"
+                                classList={{
+                                  "text-v2-text-text-muted": props.newLayoutDesigns,
+                                  "text-text-weak": !props.newLayoutDesigns,
+                                }}
+                              >
+                                {description()}
+                              </span>
+                            )}
+                          </Show>
+                        </div>
+                      </button>
+                    )
+                  }
+
+                  if (item.type === "reference") {
+                    return (
+                      <button
+                        class="w-full flex items-center gap-x-2 px-2 py-0.5"
+                        classList={{
+                          "rounded-[4px]": props.newLayoutDesigns,
+                          "rounded-md": !props.newLayoutDesigns,
+                          "bg-v2-overlay-simple-overlay-hover": props.newLayoutDesigns && props.atActive === key,
+                          "bg-surface-raised-base-hover": !props.newLayoutDesigns && props.atActive === key,
+                        }}
+                        onClick={() => props.onAtSelect(item)}
+                        onPointerMove={() => props.setAtActive(key)}
+                      >
+                        <FileIcon node={{ path: item.path, type: "directory" }} class="shrink-0 size-4" />
+                        <div
+                          class="flex items-center min-w-0"
+                          classList={{
+                            "text-[13px] leading-[calc(var(--font-size-base)*1.8)] tracking-[-0.04px] [font-weight:440]":
+                              props.newLayoutDesigns,
+                            "text-14-regular": !props.newLayoutDesigns,
+                          }}
+                        >
+                          <span
+                            class="text-text-strong whitespace-nowrap"
+                            classList={{ "text-v2-text-text-base": props.newLayoutDesigns }}
+                          >
+                            @{item.name}
+                          </span>
+                          <span
+                            class="whitespace-nowrap truncate min-w-0 ml-2"
+                            classList={{
+                              "text-v2-text-text-muted": props.newLayoutDesigns,
+                              "text-text-weak": !props.newLayoutDesigns,
+                            }}
+                          >
+                            {item.description}
+                          </span>
+                        </div>
                      </button>
                    )
                  }
@@ -75,16 +207,44 @@ export const PromptPopover: Component<PromptPopoverProps> = (props) => {

                  return (
                    <button
-                      class="w-full flex items-center gap-x-2 rounded-md px-2 py-0.5"
-                      classList={{ "bg-surface-raised-base-hover": props.atActive === key }}
+                      class="w-full flex items-center gap-x-2 px-2 py-0.5"
+                      classList={{
+                        "rounded-[4px]": props.newLayoutDesigns,
+                        "rounded-md": !props.newLayoutDesigns,
+                        "bg-v2-overlay-simple-overlay-hover": props.newLayoutDesigns && props.atActive === key,
+                        "bg-surface-raised-base-hover": !props.newLayoutDesigns && props.atActive === key,
+                      }}
                      onClick={() => props.onAtSelect(item)}
-                      onMouseEnter={() => props.setAtActive(key)}
+                      onPointerMove={() => props.setAtActive(key)}
                    >
                      <FileIcon node={{ path: item.path, type: "file" }} class="shrink-0 size-4" />
-                      <div class="flex items-center text-14-regular min-w-0">
-                        <span class="text-text-weak whitespace-nowrap truncate min-w-0">{directory}</span>
+                      <div
+                        class="flex items-center min-w-0"
+                        classList={{
+                          "text-[13px] leading-[calc(var(--font-size-base)*1.8)] tracking-[-0.04px] [font-weight:440]":
+                            props.newLayoutDesigns,
+                          "text-14-regular": !props.newLayoutDesigns,
+                        }}
+                      >
+                        <span
+                          class="whitespace-nowrap truncate min-w-0"
+                          classList={{
+                            "text-v2-text-text-muted": props.newLayoutDesigns,
+                            "text-text-weak": !props.newLayoutDesigns,
+                          }}
+                        >
+                          {directory}
+                        </span>
                        <Show when={!isDirectory}>
-                          <span class="text-text-strong whitespace-nowrap">{filename}</span>
+                          <span
+                            class="whitespace-nowrap"
+                            classList={{
+                              "text-v2-text-text-base": props.newLayoutDesigns,
+                              "text-text-strong": !props.newLayoutDesigns,
+                            }}
+                          >
+                            {filename}
+                          </span>
                        </Show>
                      </div>
                    </button>
@@ -96,41 +256,98 @@ export const PromptPopover: Component<PromptPopoverProps> = (props) => {
          <Match when={props.popover === "slash"}>
            <Show
              when={props.slashFlat.length > 0}
-              fallback={<div class="text-text-weak px-2 py-1">{props.t("prompt.popover.emptyCommands")}</div>}
+              fallback={
+                <div
+                  class="px-2 py-1"
+                  classList={{
+                    "text-v2-text-text-muted": props.newLayoutDesigns,
+                    "text-text-weak": !props.newLayoutDesigns,
+                  }}
+                >
+                  {props.t("prompt.popover.emptyCommands")}
+                </div>
+              }
            >
              <For each={props.slashFlat}>
-                {(cmd) => (
-                  <button
-                    data-slash-id={cmd.id}
-                    classList={{
-                      "w-full flex items-center justify-between gap-4 rounded-md px-2 py-1": true,
-                      "bg-surface-raised-base-hover": props.slashActive === cmd.id,
-                    }}
-                    onClick={() => props.onSlashSelect(cmd)}
-                    onMouseEnter={() => props.setSlashActive(cmd.id)}
-                  >
-                    <div class="flex items-center gap-2 min-w-0">
-                      <span class="text-14-regular text-text-strong whitespace-nowrap">/{cmd.trigger}</span>
-                      <Show when={cmd.description}>
-                        <span class="text-14-regular text-text-weak truncate">{cmd.description}</span>
-                      </Show>
-                    </div>
-                    <div class="flex items-center gap-2 shrink-0">
-                      <Show when={cmd.type === "custom" && cmd.source !== "command"}>
-                        <span class="text-11-regular text-text-subtle px-1.5 py-0.5 bg-surface-base rounded">
-                          {cmd.source === "skill"
-                            ? props.t("prompt.slash.badge.skill")
-                            : cmd.source === "mcp"
-                              ? props.t("prompt.slash.badge.mcp")
-                              : props.t("prompt.slash.badge.custom")}
+                {(cmd) => {
+                  const keybind = () => props.commandKeybind(cmd.id)
+                  const keybindParts = () => props.commandKeybindParts(cmd.id)
+                  return (
+                    <button
+                      data-slash-id={cmd.id}
+                      classList={{
+                        "w-full flex items-center justify-between gap-4 px-2 py-1": true,
+                        "rounded-[4px] scroll-my-2": props.newLayoutDesigns,
+                        "rounded-md": !props.newLayoutDesigns,
+                        "bg-v2-overlay-simple-overlay-hover": props.newLayoutDesigns && props.slashActive === cmd.id,
+                        "bg-surface-raised-base-hover": !props.newLayoutDesigns && props.slashActive === cmd.id,
+                      }}
+                      onClick={() => props.onSlashSelect(cmd)}
+                      onPointerMove={() => props.setSlashActive(cmd.id)}
+                    >
+                      <div class="flex items-center gap-2 min-w-0">
+                        <span
+                          class="whitespace-nowrap"
+                          classList={{
+                            "text-[13px] leading-[calc(var(--font-size-base)*1.8)] tracking-[-0.04px] [font-weight:440]":
+                              props.newLayoutDesigns,
+                            "text-v2-text-text-base": props.newLayoutDesigns,
+                            "text-14-regular": !props.newLayoutDesigns,
+                            "text-text-strong": !props.newLayoutDesigns,
+                          }}
+                        >
+                          /{cmd.trigger}
                        </span>
-                      </Show>
-                      <Show when={props.commandKeybind(cmd.id)}>
-                        <span class="text-12-regular text-text-subtle">{props.commandKeybind(cmd.id)}</span>
-                      </Show>
-                    </div>
-                  </button>
-                )}
+                        <Show when={cmd.description}>
+                          <span
+                            class="truncate"
+                            classList={{
+                              "text-[13px] leading-[calc(var(--font-size-base)*1.8)] tracking-[-0.04px] [font-weight:440]":
+                                props.newLayoutDesigns,
+                              "text-v2-text-text-muted": props.newLayoutDesigns,
+                              "text-14-regular": !props.newLayoutDesigns,
+                              "text-text-weak": !props.newLayoutDesigns,
+                            }}
+                          >
+                            {cmd.description}
+                          </span>
+                        </Show>
+                      </div>
+                      <div class="flex items-center gap-2 shrink-0">
+                        <Show when={cmd.type === "custom" && cmd.source !== "command"}>
+                          <Show
+                            when={props.newLayoutDesigns}
+                            fallback={
+                              <span class="text-11-regular px-1.5 py-0.5 rounded bg-surface-base text-text-subtle">
+                                {cmd.source === "skill"
+                                  ? props.t("prompt.slash.badge.skill")
+                                  : cmd.source === "mcp"
+                                    ? props.t("prompt.slash.badge.mcp")
+                                    : props.t("prompt.slash.badge.custom")}
+                              </span>
+                            }
+                          >
+                            <Tag>
+                              {cmd.source === "skill"
+                                ? props.t("prompt.slash.badge.skill")
+                                : cmd.source === "mcp"
+                                  ? props.t("prompt.slash.badge.mcp")
+                                  : props.t("prompt.slash.badge.custom")}
+                            </Tag>
+                          </Show>
+                        </Show>
+                        <Show when={props.newLayoutDesigns ? keybindParts().length > 0 : keybind()}>
+                          <Show
+                            when={props.newLayoutDesigns}
+                            fallback={<span class="text-12-regular text-text-subtle">{keybind()}</span>}
+                          >
+                            <KeybindV2 keys={keybindParts()} variant="neutral" />
+                          </Show>
+                        </Show>
+                      </div>
+                    </button>
+                  )
+                }}
              </For>
            </Show>
          </Match>
@@ -92,11 +92,17 @@ export function PromptWorkspaceSelector(props: {
          </MenuV2.Content>
        </MenuV2.Portal>
      </MenuV2>
-      <span class="hidden select-none opacity-50 sm:inline mx-1">/</span>
-      <div class="flex h-7 min-w-0 max-w-[220px] items-center gap-1.5 px-2 text-[13px] font-[440] leading-5 tracking-[-0.04px]">
-        <Icon name="branch" size="small" class="shrink-0 text-v2-icon-icon-muted" />
-        <span class="min-w-0 truncate">{props.branch || "main"}</span>
-      </div>
+      <Show when={props.branch}>
+        {(branch) => (
+          <>
+            <span class="hidden select-none opacity-50 sm:inline mx-1">/</span>
+            <div class="flex h-7 min-w-0 max-w-[220px] items-center gap-1.5 px-2 text-[13px] font-[440] leading-5 tracking-[-0.04px]">
+              <Icon name="branch" size="small" class="shrink-0 text-v2-icon-icon-muted" />
+              <span class="min-w-0 truncate">{branch()}</span>
+            </div>
+          </>
+        )}
+      </Show>
    </>
  )
 }
@@ -1,7 +1,9 @@
-import { Match, Show, Switch, createMemo } from "solid-js"
-import { Tooltip, type TooltipProps } from "@opencode-ai/ui/tooltip"
+import { Match, Show, Switch, createMemo, type ComponentProps, type JSX } from "solid-js"
 import { ProgressCircle } from "@opencode-ai/ui/progress-circle"
+import { ProgressCircleV2 } from "@opencode-ai/ui/v2/progress-circle-v2"
 import { Button } from "@opencode-ai/ui/button"
+import { IconButtonV2 } from "@opencode-ai/ui/v2/icon-button-v2"
+import { TooltipV2 } from "@opencode-ai/ui/v2/tooltip-v2"

 import { useFile } from "@/context/file"
 import { useLayout } from "@/context/layout"
@@ -9,13 +11,23 @@ import { useSync } from "@/context/sync"
 import { useLanguage } from "@/context/language"
 import { useProviders } from "@/hooks/use-providers"
 import { useSDK } from "@/context/sdk"
-import { getSessionContextMetrics } from "@/components/session/session-context-metrics"
+import { getSessionContext, getSessionTokenTotal } from "@/components/session/session-context-metrics"
 import { useSessionLayout } from "@/pages/session/session-layout"
 import { createSessionTabs } from "@/pages/session/helpers"

 interface SessionContextUsageProps {
  variant?: "button" | "indicator"
-  placement?: TooltipProps["placement"]
+  buttonAppearance?: "default" | "v2"
+  placement?: ComponentProps<typeof TooltipV2>["placement"]
+}
+
+function ContextTooltipRow(props: { name: JSX.Element; value: JSX.Element }) {
+  return (
+    <div class="flex min-w-0 items-center gap-4">
+      <span class="shrink-0 text-v2-text-text-muted">{props.name}</span>
+      <span class="ml-auto min-w-0 truncate text-right text-v2-text-text-base">{props.value}</span>
+    </div>
+  )
 }

 function openSessionContext(args: {
@@ -23,7 +35,7 @@ function openSessionContext(args: {
  layout: ReturnType<typeof useLayout>
  tabs: ReturnType<ReturnType<typeof useLayout>["tabs"]>
 }) {
-  if (!args.view.reviewPanel.opened()) args.view.reviewPanel.open()
+  args.view.reviewPanel.open(args.view.reviewPanel.opened() ? "other" : "context-button")
  if (args.layout.fileTree.opened() && args.layout.fileTree.tab() !== "all") args.layout.fileTree.setTab("all")
  void args.tabs.open("context")
  args.tabs.setActive("context")
@@ -39,12 +51,14 @@ export function SessionContextUsage(props: SessionContextUsageProps) {
  const { params, tabs, view } = useSessionLayout()

  const variant = createMemo(() => props.variant ?? "button")
+  const buttonAppearance = createMemo(() => props.buttonAppearance ?? "default")
  const tabState = createSessionTabs({
    tabs,
    pathFromTab: file.pathFromTab,
    normalizeTab: (tab) => (tab.startsWith("file://") ? file.tab(tab) : tab),
  })
  const messages = createMemo(() => (params.id ? (sync().data.message[params.id] ?? []) : []))
+  const info = createMemo(() => (params.id ? sync().session.get(params.id) : undefined))

  const usd = createMemo(
    () =>
@@ -54,21 +68,30 @@ export function SessionContextUsage(props: SessionContextUsageProps) {
      }),
  )

-  const metrics = createMemo(() => getSessionContextMetrics(messages(), [...providers.all().values()]))
-  const context = createMemo(() => metrics().context)
+  const context = createMemo(() => getSessionContext(messages(), [...providers.all().values()]))
+  const tokens = createMemo(() => info()?.tokens)
  const cost = createMemo(() => {
-    return usd().format(metrics().totalCost)
+    return usd().format(info()?.cost ?? 0)
  })
+  const contextVisible = createMemo(() => view().reviewPanel.opened() && tabState.activeTab() === "context")
+  const hasOtherTabs = createMemo(() =>
+    tabs()
+      .all()
+      .some((tab) => tab !== "context" && tab !== "review"),
+  )

  const openContext = () => {
    if (!params.id) return

-    if (tabState.activeTab() === "context") {
+    const sessionView = view()
+    if (contextVisible()) {
      tabs().close("context")
+      if (sessionView.reviewPanel.source() === "context-button" && !hasOtherTabs()) sessionView.reviewPanel.close()
      return
    }
+
    openSessionContext({
-      view: view(),
+      view: sessionView,
      layout,
      tabs: tabs(),
    })
@@ -76,38 +99,54 @@ export function SessionContextUsage(props: SessionContextUsageProps) {

  const circle = () => (
    <div class="flex items-center justify-center">
-      <ProgressCircle size={16} strokeWidth={2} percentage={context()?.usage ?? 0} />
+      <ProgressCircle
+        size={16}
+        strokeWidth={2}
+        percentage={context()?.usage ?? 0}
+        style={
+          variant() === "indicator"
+            ? {
+                "--progress-circle-background": "var(--v2-background-bg-layer-04, var(--border-weak-base))",
+                "--progress-circle-background-overlay": "var(--v2-overlay-simple-overlay-pressed, transparent)",
+                "--progress-circle-progress": "var(--v2-icon-icon-base, var(--icon-base))",
+              }
+            : undefined
+        }
+      />
+    </div>
+  )
+  const circleV2 = () => (
+    <div class="flex items-center justify-center">
+      <ProgressCircleV2 percentage={context()?.usage ?? 0} />
    </div>
  )

  const tooltipValue = () => (
-    <div>
-      <Show when={context()}>
-        {(ctx) => (
-          <>
-            <div class="flex items-center gap-2">
-              <span class="text-text-invert-strong">{ctx().total.toLocaleString(language.intl())}</span>
-              <span class="text-text-invert-base">{language.t("context.usage.tokens")}</span>
-            </div>
-            <div class="flex items-center gap-2">
-              <span class="text-text-invert-strong">{ctx().usage ?? 0}%</span>
-              <span class="text-text-invert-base">{language.t("context.usage.usage")}</span>
-            </div>
-          </>
-        )}
-      </Show>
-      <div class="flex items-center gap-2">
-        <span class="text-text-invert-strong">{cost()}</span>
-        <span class="text-text-invert-base">{language.t("context.usage.cost")}</span>
-      </div>
+    <div class="flex w-[120px] flex-col gap-2">
+      <ContextTooltipRow name={language.t("context.usage.cost")} value={cost()} />
+      <ContextTooltipRow name={language.t("context.usage.usage")} value={`${context()?.usage ?? 0}%`} />
+      <ContextTooltipRow
+        name={language.t("context.usage.tokens")}
+        value={getSessionTokenTotal(tokens())?.toLocaleString(language.intl()) ?? "0"}
+      />
    </div>
  )

  return (
    <Show when={params.id}>
-      <Tooltip value={tooltipValue()} placement={props.placement ?? "top"}>
+      <TooltipV2 value={tooltipValue()} placement={props.placement ?? "top"} shift={-8}>
        <Switch>
          <Match when={variant() === "indicator"}>{circle()}</Match>
+          <Match when={buttonAppearance() === "v2"}>
+            <IconButtonV2
+              type="button"
+              variant="ghost-muted"
+              size="large"
+              icon={circleV2()}
+              onClick={openContext}
+              aria-label={language.t("context.usage.view")}
+            />
+          </Match>
          <Match when={true}>
            <Button
              type="button"
@@ -120,7 +159,7 @@ export function SessionContextUsage(props: SessionContextUsageProps) {
            </Button>
          </Match>
        </Switch>
-      </Tooltip>
+      </TooltipV2>
    </Show>
  )
 }
@@ -1,6 +1,6 @@
 import { describe, expect, test } from "bun:test"
 import type { Message } from "@opencode-ai/sdk/v2/client"
-import { getSessionContextMetrics } from "./session-context-metrics"
+import { getSessionContext, getSessionTokenTotal } from "./session-context-metrics"

 const assistant = (
  id: string,
@@ -37,8 +37,8 @@ const user = (id: string) => {
  } as unknown as Message
 }

-describe("getSessionContextMetrics", () => {
-  test("computes totals and usage from latest assistant with tokens", () => {
+describe("getSessionContext", () => {
+  test("computes usage from latest assistant with tokens", () => {
    const messages = [
      user("u1"),
      assistant("a1", { input: 0, output: 0, reasoning: 0, read: 0, write: 0 }, 0.5),
@@ -57,45 +57,52 @@ describe("getSessionContextMetrics", () => {
      },
    ]

-    const metrics = getSessionContextMetrics(messages, providers)
+    const ctx = getSessionContext(messages, providers)

-    expect(metrics.totalCost).toBe(1.75)
-    expect(metrics.context?.message.id).toBe("a2")
-    expect(metrics.context?.total).toBe(500)
-    expect(metrics.context?.usage).toBe(50)
-    expect(metrics.context?.providerLabel).toBe("OpenAI")
-    expect(metrics.context?.modelLabel).toBe("GPT-4.1")
+    expect(ctx?.message.id).toBe("a2")
+    expect(ctx?.usage).toBe(50)
+    expect(ctx?.providerLabel).toBe("OpenAI")
+    expect(ctx?.modelLabel).toBe("GPT-4.1")
  })

  test("preserves fallback labels and null usage when model metadata is missing", () => {
    const messages = [assistant("a1", { input: 40, output: 10, reasoning: 0, read: 0, write: 0 }, 0.1, "p-1", "m-1")]
    const providers = [{ id: "p-1", models: {} }]

-    const metrics = getSessionContextMetrics(messages, providers)
+    const ctx = getSessionContext(messages, providers)

-    expect(metrics.context?.providerLabel).toBe("p-1")
-    expect(metrics.context?.modelLabel).toBe("m-1")
-    expect(metrics.context?.limit).toBeUndefined()
-    expect(metrics.context?.usage).toBeNull()
+    expect(ctx?.providerLabel).toBe("p-1")
+    expect(ctx?.modelLabel).toBe("m-1")
+    expect(ctx?.limit).toBeUndefined()
+    expect(ctx?.usage).toBeNull()
  })

  test("recomputes when message array is mutated in place", () => {
    const messages = [assistant("a1", { input: 10, output: 10, reasoning: 10, read: 10, write: 10 }, 0.25)]
    const providers = [{ id: "openai", models: {} }]

-    const one = getSessionContextMetrics(messages, providers)
+    const one = getSessionContext(messages, providers)
    messages.push(assistant("a2", { input: 100, output: 20, reasoning: 0, read: 0, write: 0 }, 0.75))
-    const two = getSessionContextMetrics(messages, providers)
+    const two = getSessionContext(messages, providers)

-    expect(one.context?.message.id).toBe("a1")
-    expect(two.context?.message.id).toBe("a2")
-    expect(two.totalCost).toBe(1)
+    expect(one?.message.id).toBe("a1")
+    expect(two?.message.id).toBe("a2")
  })

-  test("returns empty metrics when inputs are undefined", () => {
-    const metrics = getSessionContextMetrics(undefined, undefined)
+  test("returns undefined when inputs are undefined", () => {
+    const ctx = getSessionContext(undefined, undefined)

-    expect(metrics.totalCost).toBe(0)
-    expect(metrics.context).toBeUndefined()
+    expect(ctx).toBeUndefined()
+  })
+
+  test("computes stored session token totals", () => {
+    expect(
+      getSessionTokenTotal({
+        input: 10,
+        output: 20,
+        reasoning: 30,
+        cache: { read: 40, write: 50 },
+      }),
+    ).toBe(150)
  })
 })
@@ -1,4 +1,4 @@
-import type { AssistantMessage, Message } from "@opencode-ai/sdk/v2/client"
+import type { AssistantMessage, Message, Session } from "@opencode-ai/sdk/v2/client"

 type Provider = {
  id: string
@@ -21,19 +21,9 @@ type Context = {
  modelLabel: string
  limit: number | undefined
  input: number
-  output: number
-  reasoning: number
-  cacheRead: number
-  cacheWrite: number
-  total: number
  usage: number | null
 }

-type Metrics = {
-  totalCost: number
-  context: Context | undefined
-}
-
 const tokenTotal = (msg: AssistantMessage) => {
  return msg.tokens.input + msg.tokens.output + msg.tokens.reasoning + msg.tokens.cache.read + msg.tokens.cache.write
 }
@@ -47,10 +37,9 @@ const lastAssistantWithTokens = (messages: Message[]) => {
  }
 }

-const build = (messages: Message[] = [], providers: Provider[] = []): Metrics => {
-  const totalCost = messages.reduce((sum, msg) => sum + (msg.role === "assistant" ? msg.cost : 0), 0)
+const build = (messages: Message[] = [], providers: Provider[] = []): Context | undefined => {
  const message = lastAssistantWithTokens(messages)
-  if (!message) return { totalCost, context: undefined }
+  if (!message) return undefined

  const provider = providers.find((item) => item.id === message.providerID)
  const model = provider?.models[message.modelID]
@@ -58,25 +47,22 @@ const build = (messages: Message[] = [], providers: Provider[] = []): Metrics =>
  const total = tokenTotal(message)

  return {
-    totalCost,
-    context: {
-      message,
-      provider,
-      model,
-      providerLabel: provider?.name ?? message.providerID,
-      modelLabel: model?.name ?? message.modelID,
-      limit,
-      input: message.tokens.input,
-      output: message.tokens.output,
-      reasoning: message.tokens.reasoning,
-      cacheRead: message.tokens.cache.read,
-      cacheWrite: message.tokens.cache.write,
-      total,
-      usage: limit ? Math.round((total / limit) * 100) : null,
-    },
+    message,
+    provider,
+    model,
+    providerLabel: provider?.name ?? message.providerID,
+    modelLabel: model?.name ?? message.modelID,
+    limit,
+    input: message.tokens.input,
+    usage: limit ? Math.round((total / limit) * 100) : null,
  }
 }

-export function getSessionContextMetrics(messages: Message[] = [], providers: Provider[] = []) {
+export function getSessionContext(messages: Message[] = [], providers: Provider[] = []) {
  return build(messages, providers)
 }
+
+export function getSessionTokenTotal(tokens: Session["tokens"] | undefined) {
+  if (!tokens) return undefined
+  return tokens.input + tokens.output + tokens.reasoning + tokens.cache.read + tokens.cache.write
+}
@@ -15,7 +15,7 @@ import { useLanguage } from "@/context/language"
 import { useProviders } from "@/hooks/use-providers"
 import { useSDK } from "@/context/sdk"
 import { useSessionLayout } from "@/pages/session/session-layout"
-import { getSessionContextMetrics } from "./session-context-metrics"
+import { getSessionContext, getSessionTokenTotal } from "./session-context-metrics"
 import { estimateSessionContextBreakdown, type SessionContextBreakdownKey } from "./session-context-breakdown"
 import { createSessionContextFormatter } from "./session-context-format"

@@ -134,12 +134,12 @@ export function SessionContextTab() {
      }),
  )

-  const metrics = createMemo(() => getSessionContextMetrics(messages(), [...providers.all().values()]))
-  const ctx = createMemo(() => metrics().context)
+  const ctx = createMemo(() => getSessionContext(messages(), [...providers.all().values()]))
+  const tokens = createMemo(() => info()?.tokens)
  const formatter = createMemo(() => createSessionContextFormatter(language.intl()))

  const cost = createMemo(() => {
-    return usd().format(metrics().totalCost)
+    return usd().format(info()?.cost ?? 0)
  })

  const counts = createMemo(() => {
@@ -204,14 +204,14 @@ export function SessionContextTab() {
    { label: "context.stats.provider", value: providerLabel },
    { label: "context.stats.model", value: modelLabel },
    { label: "context.stats.limit", value: () => formatter().number(ctx()?.limit) },
-    { label: "context.stats.totalTokens", value: () => formatter().number(ctx()?.total) },
+    { label: "context.stats.totalTokens", value: () => formatter().number(getSessionTokenTotal(tokens())) },
    { label: "context.stats.usage", value: () => formatter().percent(ctx()?.usage) },
-    { label: "context.stats.inputTokens", value: () => formatter().number(ctx()?.input) },
-    { label: "context.stats.outputTokens", value: () => formatter().number(ctx()?.output) },
-    { label: "context.stats.reasoningTokens", value: () => formatter().number(ctx()?.reasoning) },
+    { label: "context.stats.inputTokens", value: () => formatter().number(tokens()?.input) },
+    { label: "context.stats.outputTokens", value: () => formatter().number(tokens()?.output) },
+    { label: "context.stats.reasoningTokens", value: () => formatter().number(tokens()?.reasoning) },
    {
      label: "context.stats.cacheTokens",
-      value: () => `${formatter().number(ctx()?.cacheRead)} / ${formatter().number(ctx()?.cacheWrite)}`,
+      value: () => `${formatter().number(tokens()?.cache.read)} / ${formatter().number(tokens()?.cache.write)}`,
    },
    { label: "context.stats.userMessages", value: () => counts().user.toLocaleString(language.intl()) },
    { label: "context.stats.assistantMessages", value: () => counts().assistant.toLocaleString(language.intl()) },
@@ -541,6 +541,7 @@ function SessionHeaderV2Actions(props: { state: SessionHeaderV2ActionsState }) {
      </Show>
      <Show when={props.state.reviewVisible}>
        <TooltipV2
+          class="shrink-0"
          placement="bottom"
          value={
            <>
@@ -21,7 +21,7 @@
  position: relative;
 }

-[data-titlebar-tab-slot]:not(:first-child)::before {
+[data-titlebar-tab-slot]:not(:first-child):not([data-active="true"])::before {
  content: "";
  position: absolute;
  top: 8px;
@@ -32,6 +32,10 @@
  background: var(--v2-background-bg-layer-02);
 }

+[data-titlebar-tab-slot][data-active="true"] + [data-titlebar-tab-slot]::before {
+  display: none;
+}
+
 [data-titlebar-tab] [data-slot="tab-close"]::before {
  content: "";
  position: absolute;
@@ -5,19 +5,24 @@ import { IconButtonV2 } from "@opencode-ai/ui/v2/icon-button-v2"
 import { Icon as IconV2 } from "@opencode-ai/ui/v2/icon"
 import { useGlobal } from "@/context/global"
 import { useLanguage } from "@/context/language"
-import { ServerConnection } from "@/context/server"
-import { projectForSession } from "@/pages/layout/helpers"
+import { ServerConnection, serverName } from "@/context/server"
+import { displayName, projectForSession } from "@/pages/layout/helpers"
 import { SessionTabAvatar } from "@/pages/layout/session-tab-avatar"
 import { showToast } from "@/utils/toast"
 import type { Session } from "@opencode-ai/sdk/v2"
 import { canOpenTabRename, forwardTabRef } from "./titlebar-tab-gesture"
+import { TabPreviewPopover } from "./titlebar-tab-popover"
 import "./titlebar-tab-nav.css"

+// MouseEvent.button uses 1 for the middle/wheel button.
+const MIDDLE_MOUSE_BUTTON = 1
+
 export function TabNavItem(props: {
  ref?: Ref<HTMLDivElement>
  href: string
  server: ServerConnection.Key
  session: () => Session | undefined
+  fallbackTitle?: string
  onTitleChange?: (title: string) => void
  onTitleChangeFailed?: (title: string) => void
  onClose: () => void
@@ -53,6 +58,28 @@ export function TabNavItem(props: {
    if (!session) return
    return projectForSession(session, serverCtx()?.projects.list() ?? [])
  })
+  const title = createMemo(() => props.session()?.title ?? props.fallbackTitle)
+
+  const projectName = createMemo(() => {
+    const session = props.session()
+    if (!session) return
+    return displayName(project() ?? { worktree: session.directory })
+  })
+  const previewPath = createMemo(() => {
+    const session = props.session()
+    if (!session) return
+    const home = serverCtx()?.sync.data.path.home
+    return home ? session.directory.replace(home, "~") : session.directory
+  })
+  // Only label the server when multiple servers are connected.
+  const serverLabel = createMemo(() => {
+    if (global.servers.list().length <= 1) return
+    const conn = global.servers.list().find((item) => ServerConnection.key(item) === props.server)
+    return conn ? serverName(conn) : undefined
+  })
+
+  const [popoverOpen, setPopoverOpen] = createSignal(false)
+  const previewBlocked = () => !!props.dragging || editing() || !!props.pressed || !props.session()

  const measureTitleOverflow = () => {
    if (!titleEl || editing()) {
@@ -71,7 +98,7 @@ export function TabNavItem(props: {
  }

  createEffect(() => {
-    props.session()?.title
+    title()
    props.forceTruncate
    editing()
    scheduleTitleOverflow()
@@ -130,9 +157,9 @@ export function TabNavItem(props: {
  createEffect(() => {
    if (editing()) return
    if (!titleEl) return
-    const title = props.session()?.title
-    if (title === undefined) return
-    titleEl.textContent = title
+    const value = title()
+    if (value === undefined) return
+    titleEl.textContent = value
  })

  const openRename = (event: MouseEvent) => {
@@ -168,7 +195,7 @@ export function TabNavItem(props: {
    onCleanup(cleanup)
  })

-  return (
+  const tab = (
    <div
      ref={(el) => {
        tabRoot = el
@@ -184,30 +211,35 @@ export function TabNavItem(props: {
      data-dragging={props.dragging}
      data-pressed={props.pressed}
      onMouseDown={(event) => {
-        if (event.button !== 1) return
+        if (event.button !== MIDDLE_MOUSE_BUTTON) return
+        event.preventDefault()
+        event.stopPropagation()
+      }}
+      onAuxClick={(event) => {
+        if (event.button !== MIDDLE_MOUSE_BUTTON) return
        closeTab(event)
      }}
    >
-      <Show when={props.session()}>
-        {(session) => {
-          return (
-            <a
-              data-slot="tab-link"
-              data-titlebar-tab-link
-              href={props.href}
-              draggable={false}
-              onDragStart={(event) => {
-                event.preventDefault()
-                event.stopPropagation()
-              }}
-              onClick={(event) => {
-                event.preventDefault()
-                if (editing()) return
-                if (props.suppressNavigation?.()) return
-                props.onNavigate()
-              }}
-              class="flex h-full min-w-0 flex-1 flex-row items-center gap-1.5 text-[13px] font-medium text-v2-text-text-faint group-data-[active='true']:text-v2-text-text-base group-data-[editing='true']:text-v2-text-text-base [-webkit-user-drag:none]"
-            >
+      <Show when={title() !== undefined}>
+        <a
+          data-slot="tab-link"
+          data-titlebar-tab-link
+          href={props.href}
+          draggable={false}
+          onDragStart={(event) => {
+            event.preventDefault()
+            event.stopPropagation()
+          }}
+          onClick={(event) => {
+            event.preventDefault()
+            if (editing()) return
+            if (props.suppressNavigation?.()) return
+            props.onNavigate()
+          }}
+          class="flex h-full min-w-0 flex-1 flex-row items-center gap-1.5 text-[13px] font-medium text-v2-text-text-faint group-data-[active='true']:text-v2-text-text-base group-data-[editing='true']:text-v2-text-text-base [-webkit-user-drag:none]"
+        >
+          <Show when={props.session()}>
+            {(session) => (
              <span data-slot="project-avatar-slot">
                <SessionTabAvatar
                  project={project()}
@@ -216,45 +248,45 @@ export function TabNavItem(props: {
                  activeServer={props.activeServer}
                />
              </span>
-              <span
-                ref={(el) => {
-                  titleEl = el
-                  titleEl.textContent = session().title
-                }}
-                data-slot="tab-title"
-                data-titlebar-tab-title
-                class="min-w-0 flex-1 outline-none leading-4"
-                classList={{
-                  "overflow-hidden text-clip whitespace-nowrap": !editing(),
-                  "select-text": editing(),
-                }}
-                contenteditable={editing() ? true : undefined}
-                onDblClick={openRename}
-                onKeyDown={(event) => {
-                  event.stopPropagation()
-                  if (event.key === "Enter") {
-                    event.preventDefault()
-                    void closeRename(true)
-                    return
-                  }
-                  if (event.key !== "Escape") return
-                  event.preventDefault()
-                  titleEl.textContent = session().title
-                  void closeRename(false)
-                }}
-                onBlur={() => void closeRename(true)}
-                onPointerDown={(event) => {
-                  if (!editing()) return
-                  event.stopPropagation()
-                }}
-                onClick={(event) => {
-                  if (!editing()) return
-                  event.preventDefault()
-                }}
-              />
-            </a>
-          )
-        }}
+            )}
+          </Show>
+          <span
+            ref={(el) => {
+              titleEl = el
+              titleEl.textContent = title() ?? ""
+            }}
+            data-slot="tab-title"
+            data-titlebar-tab-title
+            class="min-w-0 flex-1 outline-none leading-4"
+            classList={{
+              "overflow-hidden text-clip whitespace-nowrap": !editing(),
+              "select-text": editing(),
+            }}
+            contenteditable={editing() ? true : undefined}
+            onDblClick={openRename}
+            onKeyDown={(event) => {
+              event.stopPropagation()
+              if (event.key === "Enter") {
+                event.preventDefault()
+                void closeRename(true)
+                return
+              }
+              if (event.key !== "Escape") return
+              event.preventDefault()
+              titleEl.textContent = props.session()?.title ?? ""
+              void closeRename(false)
+            }}
+            onBlur={() => void closeRename(true)}
+            onPointerDown={(event) => {
+              if (!editing()) return
+              event.stopPropagation()
+            }}
+            onClick={(event) => {
+              if (!editing()) return
+              event.preventDefault()
+            }}
+          />
+        </a>
      </Show>

      <div data-slot="tab-close" class="group-hover:bg-[var(--tab-bg)] group-data-[active=true]:bg-[var(--tab-bg)]">
@@ -272,6 +304,23 @@ export function TabNavItem(props: {
      </div>
    </div>
  )
+
+  return (
+    <TabPreviewPopover
+      trigger={tab}
+      open={popoverOpen() && !previewBlocked()}
+      onOpenChange={(value) => {
+        if (value && previewBlocked()) return
+        setPopoverOpen(value)
+      }}
+      data={{
+        projectName: projectName(),
+        title: props.session()?.title,
+        path: previewPath(),
+        serverName: serverLabel(),
+      }}
+    />
+  )
 }

 export function DraftTabItem(props: {
@@ -302,7 +351,12 @@ export function DraftTabItem(props: {
      class="group relative flex h-7 w-full min-w-0 flex-row items-center gap-1.5 overflow-hidden rounded-[6px] bg-[var(--tab-bg)] px-1.5 [container-type:inline-size] whitespace-nowrap [--tab-bg:var(--v2-background-bg-deep)] hover:[--tab-bg:var(--v2-background-bg-layer-02)] has-[>a:focus-visible]:[--tab-bg:var(--v2-background-bg-layer-02)] data-[active='true']:[--tab-bg:var(--v2-background-bg-layer-02)] data-[dragging='true']:[--tab-bg:var(--v2-background-bg-layer-02)] data-[pressed='true']:[--tab-bg:var(--v2-background-bg-layer-02)] data-[editing='true']:[--tab-bg:var(--v2-background-bg-layer-02)]"
      classList={{ invisible: props.hidden }}
      onMouseDown={(event) => {
-        if (event.button !== 1) return
+        if (event.button !== MIDDLE_MOUSE_BUTTON) return
+        event.preventDefault()
+        event.stopPropagation()
+      }}
+      onAuxClick={(event) => {
+        if (event.button !== MIDDLE_MOUSE_BUTTON) return
        closeTab(event)
      }}
    >
@@ -0,0 +1,127 @@
+[data-component="session-tab-popover-trigger"] {
+  display: flex;
+  width: 100%;
+  min-width: 0;
+}
+
+[data-component="session-tab-popover"] {
+  z-index: 50;
+  box-sizing: border-box;
+  width: 256px;
+  display: flex;
+  flex-direction: column;
+  gap: 6px;
+  padding: 12px;
+
+  background: var(--v2-background-bg-base);
+  border-radius: 6px;
+  box-shadow: var(--v2-elevation-floating);
+
+  color: var(--v2-text-text-base);
+  font-variant-numeric: tabular-nums;
+  user-select: none;
+  pointer-events: none;
+
+  transform-origin: var(--kb-hovercard-content-transform-origin);
+  /* Entrance: instant (trying no animation — may revert to 120ms ease-out). */
+  animation: none;
+
+  &:focus-visible,
+  &:focus-within {
+    outline: none;
+  }
+
+  /* Exit: instant (trying no animation — may revert to 80ms ease-out). */
+  &[data-closed] {
+    animation: none;
+  }
+
+  /* Warm streak (rapid tab hopping): appear/disappear instantly so the enter
+     and exit animations don't repeat on every tab. */
+  &[data-instant],
+  &[data-instant][data-closed] {
+    animation: none;
+  }
+
+  [data-slot="header"] {
+    display: flex;
+    flex-direction: column;
+    gap: 6px;
+    width: 100%;
+  }
+
+  [data-slot="project"] {
+    font-weight: 440;
+    font-size: 13px;
+    line-height: 1.5;
+    letter-spacing: -0.04px;
+    color: var(--v2-text-text-muted);
+  }
+
+  [data-slot="title"] {
+    font-weight: 530;
+    font-size: 13px;
+    line-height: 1.5;
+    letter-spacing: -0.04px;
+    color: var(--v2-text-text-base);
+    overflow-wrap: anywhere;
+  }
+
+  [data-slot="row"] {
+    display: flex;
+    width: 100%;
+    min-width: 0;
+  }
+
+  [data-slot="detail"] {
+    flex: 1 0 0;
+    min-width: 0;
+    /* Wrap the full path onto the next line instead of clipping the end. */
+    overflow-wrap: anywhere;
+    font-weight: 440;
+    font-size: 13px;
+    line-height: 1.5;
+    letter-spacing: -0.04px;
+    color: var(--v2-text-text-muted);
+  }
+
+  [data-slot="server"] {
+    font-weight: 440;
+    font-size: 13px;
+    line-height: 1;
+    letter-spacing: -0.04px;
+    color: var(--v2-text-text-muted);
+    overflow: hidden;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+}
+
+@keyframes sessionTabPopoverIn {
+  from {
+    opacity: 0;
+    transform: scale(0.96);
+  }
+  to {
+    opacity: 1;
+    transform: scale(1);
+  }
+}
+
+@keyframes sessionTabPopoverOut {
+  from {
+    opacity: 1;
+    transform: scale(1);
+  }
+  to {
+    opacity: 0;
+    transform: scale(0.96);
+  }
+}
+
+@media (prefers-reduced-motion: reduce) {
+  [data-component="session-tab-popover"],
+  [data-component="session-tab-popover"][data-closed] {
+    animation: none;
+  }
+}
@@ -0,0 +1,92 @@
+import { HoverCard as Kobalte } from "@kobalte/core/hover-card"
+import { createSignal, Show, type JSXElement } from "solid-js"
+import "./titlebar-tab-popover.css"
+
+// Initial hover delay before the preview appears, per design.
+const OPEN_DELAY = 200
+// Mouse-out delay: begin closing immediately (a brief exit animation plays).
+const CLOSE_DELAY = 0
+// After a preview closes, hovering a neighbouring tab within this window skips
+// the open delay — mirrors the tooltip's skipDelayDuration so moving across
+// tabs doesn't re-wait the full delay each time.
+const SKIP_WINDOW = 500
+let lastClosedAt = 0
+
+export interface TabPreviewData {
+  projectName?: string
+  title?: string
+  path?: string
+  serverName?: string
+}
+
+export function TabPreviewPopover(props: {
+  trigger: JSXElement
+  open: boolean
+  onOpenChange: (open: boolean) => void
+  data: TabPreviewData
+}) {
+  let triggerEl: HTMLDivElement | undefined
+  // When opened during a rapid tab-hopping streak, this preview appears and
+  // disappears instantly (no repeated enter/exit animation) — only the first,
+  // "cold" preview animates. Mirrors how browsers reuse one tab tooltip.
+  const [instant, setInstant] = createSignal(false)
+
+  const warm = () => Date.now() - lastClosedAt < SKIP_WINDOW
+  // Kobalte reads openDelay lazily when the pointer enters the trigger, so this
+  // resolves the skip window per-hover.
+  const resolveOpenDelay = () => (warm() ? 0 : OPEN_DELAY)
+  const handleOpenChange = (open: boolean) => {
+    if (open) setInstant(warm())
+    else lastClosedAt = Date.now()
+    props.onOpenChange(open)
+  }
+
+  return (
+    <Kobalte
+      open={props.open}
+      onOpenChange={handleOpenChange}
+      openDelay={resolveOpenDelay()}
+      closeDelay={CLOSE_DELAY}
+      // The preview is non-interactive (pointer-events: none), so there is no
+      // safe area to traverse — leaving the tab hides it immediately.
+      ignoreSafeArea
+      placement="bottom-start"
+      gutter={6}
+    >
+      <Kobalte.Trigger ref={triggerEl} as="div" data-component="session-tab-popover-trigger" tabIndex={-1}>
+        {props.trigger}
+      </Kobalte.Trigger>
+      <Kobalte.Portal>
+        <Kobalte.Content
+          ref={(el) => {
+            // Portalled content lives outside the themed subtree, so mirror the
+            // active theme like the v2 tooltip does.
+            const theme = triggerEl?.closest("[data-theme]")?.getAttribute("data-theme")
+            if (theme) el.setAttribute("data-theme", theme)
+          }}
+          data-component="session-tab-popover"
+          data-instant={instant() || undefined}
+        >
+          <div data-slot="header">
+            <Show when={props.data.projectName}>
+              <span data-slot="project">{props.data.projectName}</span>
+            </Show>
+            <Show when={props.data.title}>
+              <span data-slot="title">{props.data.title}</span>
+            </Show>
+          </div>
+
+          <Show when={props.data.path}>
+            <div data-slot="row">
+              <span data-slot="detail">{props.data.path}</span>
+            </div>
+          </Show>
+
+          <Show when={props.data.serverName}>
+            <div data-slot="server">{props.data.serverName}</div>
+          </Show>
+        </Kobalte.Content>
+      </Kobalte.Portal>
+    </Kobalte>
+  )
+}
@@ -31,6 +31,7 @@ function SessionTabSlot(props: {
  onClose: () => void
 }) {
  const tabs = useTabs()
+  const language = useLanguage()
  const sortable = useSortable({
    get id() {
      return props.id
@@ -50,6 +51,7 @@ function SessionTabSlot(props: {
    ({ id, ctx }) => ctx.sync.session.resolve(id).catch(() => undefined),
  )
  const session = createMemo(() => cachedSession() ?? loadedSession())
+  const missingSession = createMemo(() => !!props.serverCtx() && !loadedSession.loading && !session())
  let prefetched = false

  createEffect(() => {
@@ -85,8 +87,9 @@ function SessionTabSlot(props: {
      ref={sortable.ref}
      data-titlebar-tab-slot
      data-tab-key={props.id}
+      data-active={props.active()}
      class="relative flex w-56 min-w-7 max-w-56 flex-shrink"
-      classList={{ hidden: !session() }}
+      classList={{ hidden: !session() && !missingSession() }}
    >
      <TabNavItem
        ref={(el) => {
@@ -95,6 +98,7 @@ function SessionTabSlot(props: {
        href={tabHref(props.tab)}
        server={props.tab.server}
        session={session}
+        fallbackTitle={missingSession() ? language.t("session.tab.unknown") : undefined}
        onTitleChange={(title) => {
          const value = session()
          const ctx = props.serverCtx()
@@ -140,6 +144,7 @@ function DraftTabSlot(props: {
      ref={sortable.ref}
      data-titlebar-tab-slot
      data-tab-key={props.id}
+      data-active={props.active()}
      class="relative flex w-56 min-w-7 max-w-56 flex-shrink"
    >
      <DraftTabItem
@@ -99,6 +99,8 @@ export function Titlebar(props: { update?: TitlebarUpdate }) {

  const path = () => `${location.pathname}${location.search}${location.hash}`
  const creating = createMemo(() => {
+    const route = layout.route()
+    if (route.type === "draft" || route.type === "dir-new-sesssion") return true
    if (!params.dir) return false
    if (params.id) return false
    const parts = location.pathname.replace(/\/+$/, "").split("/")
@@ -227,7 +229,8 @@ export function Titlebar(props: { update?: TitlebarUpdate }) {
      }}
      style={{
        "min-height": minHeight(),
-        "padding-left": mac() && !mobile() ? `${84 / zoom()}px` : 0,
+        // Keep native macOS traffic lights clear even when the desktop window is narrow.
+        "padding-left": mac() ? `${84 / zoom()}px` : 0,
        width: electronWindows() ? `env(titlebar-area-width, calc(100vw - ${windowsControlsWidth()}))` : undefined,
        "max-width": electronWindows()
          ? `env(titlebar-area-width, calc(100vw - ${windowsControlsWidth()}))`
@@ -466,7 +469,7 @@ export function Titlebar(props: { update?: TitlebarUpdate }) {
                  }}
                  onReorder={(keys) => tabsStoreActions.reorder(keys)}
                />
-                <Show when={!(creating() && params.dir)}>
+                <Show when={!creating()}>
                  <TooltipV2
                    placement="bottom"
                    value={
@@ -569,7 +572,7 @@ export function Titlebar(props: { update?: TitlebarUpdate }) {
                          placement="bottom"
                          title={language.t("command.session.new")}
                          keybind={command.keybind("session.new")}
-                          openDelay={2000}
+                          openDelay={800}
                        >
                          <Button
                            variant="ghost"
@@ -599,7 +602,7 @@ export function Titlebar(props: { update?: TitlebarUpdate }) {
                  >
                    <Show when={hasProjects() && nav()}>
                      <div class="flex items-center gap-0 transition-transform">
-                        <Tooltip placement="bottom" value={language.t("common.goBack")} openDelay={2000}>
+                        <Tooltip placement="bottom" value={language.t("common.goBack")} openDelay={800}>
                          <Button
                            variant="ghost"
                            icon="chevron-left"
@@ -609,7 +612,7 @@ export function Titlebar(props: { update?: TitlebarUpdate }) {
                            aria-label={language.t("common.goBack")}
                          />
                        </Tooltip>
-                        <Tooltip placement="bottom" value={language.t("common.goForward")} openDelay={2000}>
+                        <Tooltip placement="bottom" value={language.t("common.goForward")} openDelay={800}>
                          <Button
                            variant="ghost"
                            icon="chevron-right"
@@ -16,6 +16,7 @@ describe("bootstrapDirectory", () => {
      status: "loading",
      agent: [],
      command: [],
+      reference: [],
      project: "",
      projectMeta: undefined,
      icon: undefined,
@@ -35,6 +36,7 @@ describe("bootstrapDirectory", () => {
      question: {},
      mcp_ready: true,
      mcp: {},
+      mcp_resource: {},
      lsp_ready: true,
      lsp: [],
      vcs: undefined,
@@ -67,6 +69,7 @@ describe("bootstrapDirectory", () => {
        },
        permission: { list: async () => ({ data: [] }) },
        question: { list: async () => ({ data: [] }) },
+        v2: { reference: { list: async () => ({ data: { data: [] } }) } },
        mcp: {
          status: async () => {
            mcpReads.push("status")
@@ -6,6 +6,7 @@ import type {
  Project,
  ProviderAuthResponse,
  QuestionRequest,
+  ReferenceInfo,
  Session,
 } from "@opencode-ai/sdk/v2/client"
 import { showToast } from "@/utils/toast"
@@ -18,7 +19,7 @@ import type { ServerSession } from "../server-session"
 import { cmp, normalizeAgentList, normalizeProviderList } from "./utils"
 import { formatServerError } from "@/utils/server-errors"
 import { QueryClient, queryOptions } from "@tanstack/solid-query"
-import { loadMcpQuery } from "../server-sync"
+import { loadMcpQuery, loadMcpResourcesQuery } from "../server-sync"
 import { NormalizedProviderListResponse } from "@opencode-ai/session-ui/context"
 import { ScopedKey, type ServerScope } from "@/utils/server-scope"

@@ -195,6 +196,13 @@ export const loadPathQuery = (scope: ServerScope, directory: string | null, sdk:
    queryFn: () => retry(() => sdk.path.get().then((x) => x.data!)),
  })

+export const loadReferencesQuery = (scope: ServerScope, directory: string, sdk: OpencodeClient) =>
+  queryOptions<ReferenceInfo[]>({
+    queryKey: [scope, directory, "references"] as const,
+    queryFn: () => retry(() => sdk.v2.reference.list().then((x) => x.data?.data ?? [])).catch(() => []),
+    placeholderData: [],
+  })
+
 export async function bootstrapDirectory(input: {
  directory: string
  scope: ServerScope
@@ -277,6 +285,7 @@ export async function bootstrapDirectory(input: {
          }),
        ),
      input.mcp && (() => retry(() => input.sdk.command.list().then((x) => input.setStore("command", x.data ?? [])))),
+      () => input.queryClient.fetchQuery(loadReferencesQuery(input.scope, input.directory, input.sdk)),
      () =>
        retry(() =>
          input.sdk.permission.list().then((x) => {
@@ -339,6 +348,7 @@ export async function bootstrapDirectory(input: {
        ),
      () => Promise.resolve(input.loadSessions(input.directory)),
      input.mcp && (() => input.queryClient.fetchQuery(loadMcpQuery(input.scope, input.directory, input.sdk))),
+      input.mcp && (() => input.queryClient.fetchQuery(loadMcpResourcesQuery(input.scope, input.directory, input.sdk))),
      () =>
        input.queryClient.fetchQuery(loadProvidersQuery(input.scope, input.directory, input.sdk)).catch((err) => {
          const project = getFilename(input.directory)
@@ -34,7 +34,9 @@ const queryOptionsApi = {
  }),
  agents: (directory: string) => ({ queryKey: [directory, "agents"], queryFn: async () => [] }),
  mcp: (directory: string) => ({ queryKey: [directory, "mcp"], queryFn: async () => ({}) }),
+  mcpResources: (directory: string) => ({ queryKey: [directory, "mcpResources"], queryFn: async () => ({}) }),
  lsp: (directory: string) => ({ queryKey: [directory, "lsp"], queryFn: async () => [] }),
+  references: (directory: string) => ({ queryKey: [directory, "references"], queryFn: async () => [] }),
  sessions: (directory: string) => ({ queryKey: [directory, "loadSessions"] as const }),
 } as unknown as QueryOptionsApi

@@ -197,14 +199,18 @@ describe("createChildStoreManager", () => {
    try {
      if (!manager) throw new Error("manager required")
      const [store, setStore] = manager.child("/project", { bootstrap: false })
-      expect(querySingles.length - offset).toBe(4)
+      expect(querySingles.length - offset).toBe(6)
      const query = querySingles[offset + 1]
+      const resourceQuery = querySingles[offset + 2]
      if (!query) throw new Error("query required")
+      if (!resourceQuery) throw new Error("resource query required")
      expect(query().enabled).toBe(false)
+      expect(resourceQuery().enabled).toBe(false)

      setStore("status", "complete")
      manager.child("/project", { bootstrap: false, mcp: true })
      expect(query().enabled).toBe(true)
+      expect(resourceQuery().enabled).toBe(true)
      expect(store.mcp).toEqual({ demo: { status: "disabled" } })
      expect(mcpLoads).toEqual(["/project"])

@@ -185,8 +185,10 @@ export function createChildStoreManager(input: {

          const pathQuery = useQuery(() => input.queryOptions.path(key))
          const mcpQuery = useQuery(() => ({ ...input.queryOptions.mcp(key), enabled: mcpEnabled() }))
+          const mcpResourceQuery = useQuery(() => ({ ...input.queryOptions.mcpResources(key), enabled: mcpEnabled() }))
          const lspQuery = useQuery(() => input.queryOptions.lsp(key))
          const providerQuery = useQuery(() => input.queryOptions.providers(key))
+          const referenceQuery = useQuery(() => input.queryOptions.references(key))

          const child = createStore<State>({
            project: "",
@@ -210,6 +212,9 @@ export function createChildStoreManager(input: {
            status: "loading" as const,
            agent: [],
            command: [],
+            get reference() {
+              return referenceQuery.isLoading ? [] : (referenceQuery.data ?? [])
+            },
            session: [],
            sessionTotal: 0,
            session_status: {},
@@ -227,6 +232,9 @@ export function createChildStoreManager(input: {
            get mcp() {
              return mcpQuery.isLoading ? {} : (mcpQuery.data ?? {})
            },
+            get mcp_resource() {
+              return mcpResourceQuery.isLoading ? {} : (mcpResourceQuery.data ?? {})
+            },
            get lsp_ready() {
              return !lspQuery.isLoading
            },
@@ -112,6 +112,7 @@ export function applyDirectoryEvent(input: {
  push: (directory: string) => void
  directory: string
  loadLsp: () => void
+  loadReferences?: () => void
  vcsCache?: VcsCache
  setSessionTodo?: (sessionID: string, todos: Todo[] | undefined) => void
  retainedLimit?: number
@@ -404,5 +405,9 @@ export function applyDirectoryEvent(input: {
      input.loadLsp()
      break
    }
+    case "reference.updated": {
+      input.loadReferences?.()
+      break
+    }
  }
 }
@@ -3,12 +3,14 @@ import type {
  Command,
  Config,
  LspStatus,
+  McpResource,
  McpStatus,
  Message,
  Part,
  Path,
  PermissionRequest,
  QuestionRequest,
+  ReferenceInfo,
  Session,
  SessionStatus,
  SnapshotFileDiff,
@@ -34,6 +36,7 @@ export type State = {
  status: "loading" | "partial" | "complete"
  agent: Agent[]
  command: Command[]
+  reference: ReferenceInfo[]
  project: string
  projectMeta: ProjectMeta | undefined
  icon: string | undefined
@@ -63,6 +66,9 @@ export type State = {
  mcp: {
    [name: string]: McpStatus
  }
+  mcp_resource: {
+    [key: string]: McpResource
+  }
  lsp_ready: boolean
  lsp: LspStatus[]
  vcs: VcsInfo | undefined
@@ -28,6 +28,7 @@ const DEFAULT_SIDEBAR_WIDTH = 344
 const DEFAULT_FILE_TREE_WIDTH = 200
 const DEFAULT_SESSION_WIDTH = 600
 const DEFAULT_TERMINAL_HEIGHT = 280
+const DEFAULT_REVIEW_PANEL_OPENED = false
 export type AvatarColorKey = (typeof AVATAR_COLOR_KEYS)[number]

 export function getAvatarColors(key?: string) {
@@ -77,6 +78,7 @@ export type LocalProject = Partial<Project> & { worktree: string; expanded: bool
 export type HomeProjectSelection = { server: ServerConnection.Key; directory?: string }

 export type ReviewDiffStyle = "unified" | "split"
+export type ReviewPanelSource = "context-button" | "other"

 export type LayoutRoute =
  | { type: "home" }
@@ -210,7 +212,8 @@ export const { use: useLayout, provider: LayoutProvider } = createSimpleContext(
        if (!isRecord(review)) return review
        if (typeof review.panelOpened === "boolean") return review

-        const opened = isRecord(fileTree) && typeof fileTree.opened === "boolean" ? fileTree.opened : true
+        const opened =
+          isRecord(fileTree) && typeof fileTree.opened === "boolean" ? fileTree.opened : DEFAULT_REVIEW_PANEL_OPENED
        return {
          ...review,
          panelOpened: opened,
@@ -279,7 +282,7 @@ export const { use: useLayout, provider: LayoutProvider } = createSimpleContext(
        },
        review: {
          diffStyle: "split" as ReviewDiffStyle,
-          panelOpened: true,
+          panelOpened: DEFAULT_REVIEW_PANEL_OPENED,
        },
        fileTree: {
          opened: false,
@@ -302,6 +305,9 @@ export const { use: useLayout, provider: LayoutProvider } = createSimpleContext(
        },
      }),
    )
+    const [ephemeral, setEphemeral] = createStore({
+      reviewPanelSource: "other" as ReviewPanelSource,
+    })

    const MAX_SESSION_KEYS = 50
    const PENDING_MESSAGE_TTL_MS = 2 * 60 * 1000
@@ -662,7 +668,7 @@ export const { use: useLayout, provider: LayoutProvider } = createSimpleContext(
        diffStyle: createMemo(() => store.review?.diffStyle ?? "split"),
        setDiffStyle(diffStyle: ReviewDiffStyle) {
          if (!store.review) {
-            setStore("review", { diffStyle, panelOpened: true })
+            setStore("review", { diffStyle, panelOpened: DEFAULT_REVIEW_PANEL_OPENED })
            return
          }
          setStore("review", "diffStyle", diffStyle)
@@ -777,7 +783,8 @@ export const { use: useLayout, provider: LayoutProvider } = createSimpleContext(
        const key = createSessionKeyReader(sessionKey, ensureKey)
        const s = createMemo(() => store.sessionView[key()] ?? { scroll: {} })
        const terminalOpened = createMemo(() => store.terminal?.opened ?? false)
-        const reviewPanelOpened = createMemo(() => store.review?.panelOpened ?? true)
+        const reviewPanelOpened = createMemo(() => store.review?.panelOpened ?? DEFAULT_REVIEW_PANEL_OPENED)
+        const reviewPanelSource = createMemo(() => (reviewPanelOpened() ? ephemeral.reviewPanelSource : "other"))

        function setTerminalOpened(next: boolean) {
          const current = store.terminal
@@ -791,16 +798,26 @@ export const { use: useLayout, provider: LayoutProvider } = createSimpleContext(
          setStore("terminal", "opened", next)
        }

-        function setReviewPanelOpened(next: boolean) {
+        function setReviewPanelOpened(next: boolean, source: ReviewPanelSource) {
+          const nextSource = next ? source : "other"
          const current = store.review
          if (!current) {
-            setStore("review", { diffStyle: "split" as ReviewDiffStyle, panelOpened: next })
+            batch(() => {
+              setStore("review", { diffStyle: "split" as ReviewDiffStyle, panelOpened: next })
+              setEphemeral("reviewPanelSource", nextSource)
+            })
            return
          }

-          const value = current.panelOpened ?? true
-          if (value === next) return
-          setStore("review", "panelOpened", next)
+          const value = current.panelOpened ?? DEFAULT_REVIEW_PANEL_OPENED
+          if (value === next) {
+            if (ephemeral.reviewPanelSource !== nextSource) setEphemeral("reviewPanelSource", nextSource)
+            return
+          }
+          batch(() => {
+            setStore("review", "panelOpened", next)
+            setEphemeral("reviewPanelSource", nextSource)
+          })
        }

        return {
@@ -836,14 +853,15 @@ export const { use: useLayout, provider: LayoutProvider } = createSimpleContext(
          },
          reviewPanel: {
            opened: reviewPanelOpened,
-            open() {
-              setReviewPanelOpened(true)
+            source: reviewPanelSource,
+            open(source: ReviewPanelSource = "other") {
+              setReviewPanelOpened(true, source)
            },
            close() {
-              setReviewPanelOpened(false)
+              setReviewPanelOpened(false, "other")
            },
            toggle() {
-              setReviewPanelOpened(!reviewPanelOpened())
+              setReviewPanelOpened(!reviewPanelOpened(), "other")
            },
          },
          review: {
@@ -1,7 +1,7 @@
 import { createSimpleContext } from "@opencode-ai/ui/context"
 import { base64Encode } from "@opencode-ai/core/util/encode"
 import { useParams } from "@solidjs/router"
-import { batch, createEffect, createMemo } from "solid-js"
+import { batch, createEffect, createMemo, startTransition } from "solid-js"
 import { createStore } from "solid-js/store"
 import { useModels } from "@/context/models"
 import { useProviders } from "@/hooks/use-providers"
@@ -80,6 +80,7 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
    const [store, setStore] = createStore<{
      current?: string
      draft?: State
+      promoting?: State
      last?: {
        type: "agent" | "model" | "variant"
        agent?: string
@@ -123,7 +124,7 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({

    const scope = createMemo<State | undefined>(() => {
      const session = id()
-      if (!session) return store.draft
+      if (!session) return store.draft ?? store.promoting
      return saved.session[session] ?? handoff.get(handoffKey(serverSDK().scope, sdk().directory, session))
    })

@@ -136,11 +137,13 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
      if (!next) return
      if (saved.session[session] !== undefined) {
        handoff.delete(key)
+        setStore("promoting", undefined)
        return
      }

      setSaved("session", session, clone(next))
      handoff.delete(key)
+      setStore("promoting", undefined)
    })

    const configuredModel = () => {
@@ -294,19 +297,21 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
        model.set({ providerID: entry.provider.id, modelID: entry.id })
      },
      set(item: ModelKey | undefined, options?: { recent?: boolean }) {
-        batch(() => {
-          setStore("last", {
-            type: "model",
-            agent: agent.current()?.name,
-            model: item ?? null,
-            variant: selected(),
-          })
-          write({ model: item })
-          if (!item) return
-          models.setVisibility(item, true)
-          if (!options?.recent) return
-          models.recent.push(item)
-        })
+        startTransition(() =>
+          batch(() => {
+            setStore("last", {
+              type: "model",
+              agent: agent.current()?.name,
+              model: item ?? null,
+              variant: selected(),
+            })
+            write({ model: item })
+            if (!item) return
+            models.setVisibility(item, true)
+            if (!options?.recent) return
+            models.recent.push(item)
+          }),
+        )
      },
      visible(item: ModelKey) {
        return models.visible(item)
@@ -335,19 +340,21 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
          return Object.keys(item.variants)
        },
        set(value: string | undefined) {
-          batch(() => {
-            const model = current()
-            setStore("last", {
-              type: "variant",
-              agent: agent.current()?.name,
-              model: model ? { providerID: model.provider.id, modelID: model.id } : null,
-              variant: value ?? null,
-            })
-            write({ variant: value ?? null })
-            if (model) {
-              models.variant.set({ providerID: model.provider.id, modelID: model.id }, value ?? undefined)
-            }
-          })
+          startTransition(() =>
+            batch(() => {
+              const model = current()
+              setStore("last", {
+                type: "variant",
+                agent: agent.current()?.name,
+                model: model ? { providerID: model.provider.id, modelID: model.id } : null,
+                variant: value ?? null,
+              })
+              write({ variant: value ?? null })
+              if (model) {
+                models.variant.set({ providerID: model.provider.id, modelID: model.id }, value ?? undefined)
+              }
+            }),
+          )
        },
        cycle() {
          const items = this.list()
@@ -369,19 +376,19 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
      agent,
      session: {
        reset() {
-          setStore("draft", undefined)
+          setStore({ draft: undefined, promoting: undefined })
        },
        promote(dir: string, session: string) {
          const next = clone(snapshot())
          if (!next) return
+          const key = handoffKey(serverSDK().scope, dir, session)
+          handoff.set(key, next)

          if (dir === sdk().directory) {
            setSaved("session", session, next)
-            setStore("draft", undefined)
-            return
          }

-          handoff.set(handoffKey(serverSDK().scope, dir, session), next)
+          setStore("promoting", next)
          setStore("draft", undefined)
        },
        restore(msg: { sessionID: string; agent: string; model: ModelKey }) {
@@ -1,9 +1,9 @@
 import { createStore, reconcile } from "solid-js/store"
-import { type Accessor, batch, createEffect, createMemo, onCleanup } from "solid-js"
-import { useParams } from "@solidjs/router"
+import { type Accessor, batch, createEffect, createMemo, createRoot, getOwner, onCleanup } from "solid-js"
+import { useParams, useSearchParams } from "@solidjs/router"
 import { createSimpleContext } from "@opencode-ai/ui/context"
-import { useServerSDK } from "./server-sdk"
-import { useServerSync } from "./server-sync"
+import type { ServerSDK } from "./server-sdk"
+import type { ServerSync } from "./server-sync"
 import { usePlatform } from "@/context/platform"
 import { useLanguage } from "@/context/language"
 import { useSettings } from "@/context/settings"
@@ -12,6 +12,11 @@ import { decode64 } from "@/utils/base64"
 import { EventSessionError } from "@opencode-ai/sdk/v2"
 import { Persist, persisted } from "@/utils/persist"
 import { playSoundById } from "@/utils/sound"
+import { useGlobal } from "./global"
+import { ServerConnection, useServer } from "./server"
+import { type DraftTab, useTabs } from "./tabs"
+import { requireServerKey } from "@/utils/session-route"
+import type { ServerScope } from "@/utils/server-scope"

 type NotificationBase = {
  directory?: string
@@ -107,267 +112,360 @@ function buildNotificationIndex(list: Notification[]) {
 export const { use: useNotification, provider: NotificationProvider } = createSimpleContext({
  name: "Notification",
  gate: false,
-  init: (props: { directory?: Accessor<string | undefined>; sessionID?: Accessor<string | undefined> }) => {
-    const params = useParams()
-    const serverSDK = useServerSDK()
-    const serverSync = useServerSync()
+  init: () => {
+    const params = useParams<{ serverKey?: string; dir?: string; id?: string }>()
+    const [search] = useSearchParams<{ draftId?: string }>()
+    const global = useGlobal()
+    const server = useServer()
+    const tabs = useTabs()
    const platform = usePlatform()
    const settings = useSettings()
    const language = useLanguage()
+    const owner = getOwner()
+    const states = new Map<ServerScope, { dispose: () => void; state: NotificationState }>()

-    const empty: Notification[] = []
-
-    const currentDirectory = createMemo(() => {
-      return props.directory?.() ?? decode64(params.dir)
+    const activeServer = createMemo(() => {
+      if (params.serverKey) return requireServerKey(params.serverKey)
+      if (search.draftId) {
+        const draft = tabs.store.find((tab): tab is DraftTab => tab.type === "draft" && tab.draftID === search.draftId)
+        if (draft) return draft.server
+      }
+      return server.key
    })
+    const activeDirectory = createMemo(() => decode64(params.dir))
+    const activeSession = createMemo(() => params.id)

-    const currentSession = createMemo(() => props.sessionID?.() ?? params.id)
-
-    const [store, setStore, _, ready] = persisted(
-      Persist.serverGlobal(serverSDK().scope, "notification", ["notification.v1"]),
-      createStore({
-        list: [] as Notification[],
-      }),
-    )
-    const [index, setIndex] = createStore<NotificationIndex>(buildNotificationIndex(store.list))
-
-    const meta = { pruned: false, disposed: false }
-
-    const updateUnseen = (scope: "session" | "project", key: string, unseen: Notification[]) => {
-      setIndex(scope, "unseen", key, unseen)
-      setIndex(scope, "unseenCount", key, unseen.length)
-      setIndex(
-        scope,
-        "unseenHasError",
-        key,
-        unseen.some((notification) => notification.type === "error"),
+    const ensure = (key: ServerConnection.Key) => {
+      const conn = global.servers.list().find((item) => ServerConnection.key(item) === key)
+      if (!conn) throw new Error(`Notification server not found: ${key}`)
+      const ctx = global.ensureServerCtx(conn)
+      const existing = states.get(ctx.sdk.scope)
+      if (existing) return existing.state
+      const root = createRoot(
+        (dispose) => ({
+          dispose,
+          state: createServerNotificationState({
+            sdk: ctx.sdk,
+            sync: ctx.sync,
+            active: () => server.scope(activeServer()) === ctx.sdk.scope,
+            directory: activeDirectory,
+            sessionID: activeSession,
+            platform,
+            settings,
+            language,
+          }),
+        }),
+        owner ?? undefined,
      )
-    }
-
-    const appendToIndex = (notification: Notification) => {
-      if (notification.session) {
-        setIndex("session", "all", notification.session, (all = []) => [...all, notification])
-        if (!notification.viewed) {
-          setIndex("session", "unseen", notification.session, (unseen = []) => [...unseen, notification])
-          setIndex("session", "unseenCount", notification.session, (count = 0) => count + 1)
-          if (notification.type === "error") setIndex("session", "unseenHasError", notification.session, true)
-        }
-      }
-
-      if (notification.directory) {
-        setIndex("project", "all", notification.directory, (all = []) => [...all, notification])
-        if (!notification.viewed) {
-          setIndex("project", "unseen", notification.directory, (unseen = []) => [...unseen, notification])
-          setIndex("project", "unseenCount", notification.directory, (count = 0) => count + 1)
-          if (notification.type === "error") setIndex("project", "unseenHasError", notification.directory, true)
-        }
-      }
-    }
-
-    const removeFromIndex = (notification: Notification) => {
-      if (notification.session) {
-        setIndex("session", "all", notification.session, (all = []) => all.filter((n) => n !== notification))
-        if (!notification.viewed) {
-          const unseen = (index.session.unseen[notification.session] ?? empty).filter((n) => n !== notification)
-          updateUnseen("session", notification.session, unseen)
-        }
-      }
-
-      if (notification.directory) {
-        setIndex("project", "all", notification.directory, (all = []) => all.filter((n) => n !== notification))
-        if (!notification.viewed) {
-          const unseen = (index.project.unseen[notification.directory] ?? empty).filter((n) => n !== notification)
-          updateUnseen("project", notification.directory, unseen)
-        }
-      }
+      states.set(ctx.sdk.scope, root)
+      return root.state
    }

    createEffect(() => {
-      if (!ready()) return
-      if (meta.pruned) return
-      meta.pruned = true
-      const list = pruneNotifications(store.list)
-      batch(() => {
-        setStore("list", list)
-        setIndex(reconcile(buildNotificationIndex(list), { merge: false }))
+      global.servers.list().forEach((conn) => ensure(ServerConnection.key(conn)))
+    })
+
+    createEffect(() => {
+      const scopes = new Set(global.servers.list().map((conn) => server.scope(ServerConnection.key(conn))))
+      states.forEach((value, scope) => {
+        if (scopes.has(scope)) return
+        value.dispose()
+        states.delete(scope)
      })
    })

-    const append = (notification: Notification) => {
-      const list = pruneNotifications([...store.list, notification])
-      const keep = new Set(list)
-      const removed = store.list.filter((n) => !keep.has(n))
+    onCleanup(() => states.forEach((value) => value.dispose()))

-      batch(() => {
-        if (keep.has(notification)) appendToIndex(notification)
-        removed.forEach((n) => removeFromIndex(n))
-        setStore("list", list)
-      })
-    }
-
-    const lookup = async (directory: string, sessionID?: string) => {
-      if (!sessionID) return undefined
-      const sync = serverSync().ensureDirSyncContext(directory)
-      const session = sync.session.get(sessionID)
-      if (session) return session
-      return sync.session
-        .sync(sessionID)
-        .then(() => sync.session.get(sessionID))
-        .catch(() => undefined)
-    }
-
-    const viewedInCurrentSession = (directory: string, sessionID?: string) => {
-      const activeDirectory = currentDirectory()
-      const activeSession = currentSession()
-      if (!activeDirectory) return false
-      if (!activeSession) return false
-      if (!sessionID) return false
-      if (directory !== activeDirectory) return false
-      return sessionID === activeSession
-    }
-
-    const handleSessionIdle = (directory: string, event: { properties: { sessionID?: string } }, time: number) => {
-      const sessionID = event.properties.sessionID
-      void lookup(directory, sessionID).then((session) => {
-        if (meta.disposed) return
-        if (!session) return
-        if (session.parentID) return
-
-        if (settings.sounds.agentEnabled()) {
-          void playSoundById(settings.sounds.agent())
-        }
-
-        append({
-          directory,
-          time,
-          viewed: viewedInCurrentSession(directory, sessionID),
-          type: "turn-complete",
-          session: sessionID,
-        })
-
-        const href = `/${base64Encode(directory)}/session/${sessionID}`
-        if (settings.notifications.agent()) {
-          void platform.notify(language.t("notification.session.responseReady.title"), session.title ?? sessionID, href)
-        }
-      })
-    }
-
-    const handleSessionError = (
-      directory: string,
-      event: { properties: { sessionID?: string; error?: EventSessionError["properties"]["error"] } },
-      time: number,
-    ) => {
-      const sessionID = event.properties.sessionID
-      void lookup(directory, sessionID).then((session) => {
-        if (meta.disposed) return
-        if (session?.parentID) return
-
-        if (settings.sounds.errorsEnabled()) {
-          void playSoundById(settings.sounds.errors())
-        }
-
-        const error = "error" in event.properties ? event.properties.error : undefined
-        append({
-          directory,
-          time,
-          viewed: viewedInCurrentSession(directory, sessionID),
-          type: "error",
-          session: sessionID ?? "global",
-          error,
-        })
-        const description =
-          session?.title ??
-          (typeof error === "string" ? error : language.t("notification.session.error.fallbackDescription"))
-        const href = sessionID ? `/${base64Encode(directory)}/session/${sessionID}` : `/${base64Encode(directory)}`
-        if (settings.notifications.errors()) {
-          void platform.notify(language.t("notification.session.error.title"), description, href)
-        }
-      })
-    }
-
-    const unsub = serverSDK().event.listen((e) => {
-      const event = e.details
-      if (event.type !== "session.idle" && event.type !== "session.error") return
-
-      const directory = e.name
-      const time = Date.now()
-      if (event.type === "session.idle") {
-        handleSessionIdle(directory, event, time)
-        return
-      }
-      handleSessionError(directory, event, time)
-    })
-    onCleanup(() => {
-      meta.disposed = true
-      unsub()
-    })
+    const selected = () => ensure(activeServer())

    return {
-      ready,
+      ready: () => selected().ready(),
+      ensureServerState: ensure,
      session: {
-        all(session: string) {
-          return index.session.all[session] ?? empty
-        },
-        unseen(session: string) {
-          return index.session.unseen[session] ?? empty
-        },
-        unseenCount(session: string) {
-          return index.session.unseenCount[session] ?? 0
-        },
-        unseenHasError(session: string) {
-          return index.session.unseenHasError[session] ?? false
-        },
-        markViewed(session: string) {
-          const unseen = index.session.unseen[session] ?? empty
-          if (!unseen.length) return
-
-          const projects = [
-            ...new Set(unseen.flatMap((notification) => (notification.directory ? [notification.directory] : []))),
-          ]
-          batch(() => {
-            setStore("list", (n) => n.session === session && !n.viewed, "viewed", true)
-            updateUnseen("session", session, [])
-            projects.forEach((directory) => {
-              const next = (index.project.unseen[directory] ?? empty).filter(
-                (notification) => notification.session !== session,
-              )
-              updateUnseen("project", directory, next)
-            })
-          })
-        },
+        all: (session: string) => selected().session.all(session),
+        unseen: (session: string) => selected().session.unseen(session),
+        unseenCount: (session: string) => selected().session.unseenCount(session),
+        unseenHasError: (session: string) => selected().session.unseenHasError(session),
+        markViewed: (session: string) => selected().session.markViewed(session),
      },
      project: {
-        all(directory: string) {
-          return index.project.all[directory] ?? empty
-        },
-        unseen(directory: string) {
-          return index.project.unseen[directory] ?? empty
-        },
-        unseenCount(directory: string) {
-          return index.project.unseenCount[directory] ?? 0
-        },
-        unseenHasError(directory: string) {
-          return index.project.unseenHasError[directory] ?? false
-        },
-        markViewed(directory: string) {
-          const unseen = index.project.unseen[directory] ?? empty
-          if (!unseen.length) return
-
-          const sessions = [
-            ...new Set(unseen.flatMap((notification) => (notification.session ? [notification.session] : []))),
-          ]
-          batch(() => {
-            setStore("list", (n) => n.directory === directory && !n.viewed, "viewed", true)
-            updateUnseen("project", directory, [])
-            sessions.forEach((session) => {
-              const next = (index.session.unseen[session] ?? empty).filter(
-                (notification) => notification.directory !== directory,
-              )
-              updateUnseen("session", session, next)
-            })
-          })
-        },
+        all: (directory: string) => selected().project.all(directory),
+        unseen: (directory: string) => selected().project.unseen(directory),
+        unseenCount: (directory: string) => selected().project.unseenCount(directory),
+        unseenHasError: (directory: string) => selected().project.unseenHasError(directory),
+        markViewed: (directory: string) => selected().project.markViewed(directory),
      },
    }
  },
 })
+
+type NotificationState = ReturnType<typeof createServerNotificationState>
+
+function createServerNotificationState(input: {
+  sdk: ServerSDK
+  sync: ServerSync
+  active: Accessor<boolean>
+  directory: Accessor<string | undefined>
+  sessionID: Accessor<string | undefined>
+  platform: ReturnType<typeof usePlatform>
+  settings: ReturnType<typeof useSettings>
+  language: ReturnType<typeof useLanguage>
+}) {
+  const serverSDK = () => input.sdk
+  const serverSync = () => input.sync
+  const platform = input.platform
+  const settings = input.settings
+  const language = input.language
+
+  const empty: Notification[] = []
+
+  const currentDirectory = input.directory
+  const currentSession = input.sessionID
+
+  const [store, setStore, _, ready] = persisted(
+    Persist.serverGlobal(serverSDK().scope, "notification", ["notification.v1"]),
+    createStore({
+      list: [] as Notification[],
+    }),
+  )
+  const [index, setIndex] = createStore<NotificationIndex>(buildNotificationIndex(store.list))
+
+  const meta = { pruned: false, disposed: false }
+
+  const updateUnseen = (scope: "session" | "project", key: string, unseen: Notification[]) => {
+    setIndex(scope, "unseen", key, unseen)
+    setIndex(scope, "unseenCount", key, unseen.length)
+    setIndex(
+      scope,
+      "unseenHasError",
+      key,
+      unseen.some((notification) => notification.type === "error"),
+    )
+  }
+
+  const appendToIndex = (notification: Notification) => {
+    if (notification.session) {
+      setIndex("session", "all", notification.session, (all = []) => [...all, notification])
+      if (!notification.viewed) {
+        setIndex("session", "unseen", notification.session, (unseen = []) => [...unseen, notification])
+        setIndex("session", "unseenCount", notification.session, (count = 0) => count + 1)
+        if (notification.type === "error") setIndex("session", "unseenHasError", notification.session, true)
+      }
+    }
+
+    if (notification.directory) {
+      setIndex("project", "all", notification.directory, (all = []) => [...all, notification])
+      if (!notification.viewed) {
+        setIndex("project", "unseen", notification.directory, (unseen = []) => [...unseen, notification])
+        setIndex("project", "unseenCount", notification.directory, (count = 0) => count + 1)
+        if (notification.type === "error") setIndex("project", "unseenHasError", notification.directory, true)
+      }
+    }
+  }
+
+  const removeFromIndex = (notification: Notification) => {
+    if (notification.session) {
+      setIndex("session", "all", notification.session, (all = []) => all.filter((n) => n !== notification))
+      if (!notification.viewed) {
+        const unseen = (index.session.unseen[notification.session] ?? empty).filter((n) => n !== notification)
+        updateUnseen("session", notification.session, unseen)
+      }
+    }
+
+    if (notification.directory) {
+      setIndex("project", "all", notification.directory, (all = []) => all.filter((n) => n !== notification))
+      if (!notification.viewed) {
+        const unseen = (index.project.unseen[notification.directory] ?? empty).filter((n) => n !== notification)
+        updateUnseen("project", notification.directory, unseen)
+      }
+    }
+  }
+
+  createEffect(() => {
+    if (!ready()) return
+    if (meta.pruned) return
+    meta.pruned = true
+    const list = pruneNotifications(store.list)
+    batch(() => {
+      setStore("list", list)
+      setIndex(reconcile(buildNotificationIndex(list), { merge: false }))
+    })
+  })
+
+  const append = (notification: Notification) => {
+    const list = pruneNotifications([...store.list, notification])
+    const keep = new Set(list)
+    const removed = store.list.filter((n) => !keep.has(n))
+
+    batch(() => {
+      if (keep.has(notification)) appendToIndex(notification)
+      removed.forEach((n) => removeFromIndex(n))
+      setStore("list", list)
+    })
+  }
+
+  const lookup = async (directory: string, sessionID?: string) => {
+    if (!sessionID) return undefined
+    const sync = serverSync().ensureDirSyncContext(directory)
+    const session = sync.session.get(sessionID)
+    if (session) return session
+    return sync.session
+      .sync(sessionID)
+      .then(() => sync.session.get(sessionID))
+      .catch(() => undefined)
+  }
+
+  const viewedInCurrentSession = (directory: string, sessionID?: string) => {
+    if (!input.active()) return false
+    const activeDirectory = currentDirectory()
+    const activeSession = currentSession()
+    if (!activeSession) return false
+    if (!sessionID) return false
+    if (activeDirectory && directory !== activeDirectory) return false
+    return sessionID === activeSession
+  }
+
+  const handleSessionIdle = (directory: string, event: { properties: { sessionID?: string } }, time: number) => {
+    const sessionID = event.properties.sessionID
+    void lookup(directory, sessionID).then((session) => {
+      if (meta.disposed) return
+      if (!session) return
+      if (session.parentID) return
+
+      if (settings.sounds.agentEnabled()) {
+        void playSoundById(settings.sounds.agent())
+      }
+
+      append({
+        directory,
+        time,
+        viewed: viewedInCurrentSession(directory, sessionID),
+        type: "turn-complete",
+        session: sessionID,
+      })
+
+      const href = `/${base64Encode(directory)}/session/${sessionID}`
+      if (settings.notifications.agent()) {
+        void platform.notify(language.t("notification.session.responseReady.title"), session.title ?? sessionID, href)
+      }
+    })
+  }
+
+  const handleSessionError = (
+    directory: string,
+    event: { properties: { sessionID?: string; error?: EventSessionError["properties"]["error"] } },
+    time: number,
+  ) => {
+    const sessionID = event.properties.sessionID
+    void lookup(directory, sessionID).then((session) => {
+      if (meta.disposed) return
+      if (session?.parentID) return
+
+      if (settings.sounds.errorsEnabled()) {
+        void playSoundById(settings.sounds.errors())
+      }
+
+      const error = "error" in event.properties ? event.properties.error : undefined
+      append({
+        directory,
+        time,
+        viewed: viewedInCurrentSession(directory, sessionID),
+        type: "error",
+        session: sessionID ?? "global",
+        error,
+      })
+      const description =
+        session?.title ??
+        (typeof error === "string" ? error : language.t("notification.session.error.fallbackDescription"))
+      const href = sessionID ? `/${base64Encode(directory)}/session/${sessionID}` : `/${base64Encode(directory)}`
+      if (settings.notifications.errors()) {
+        void platform.notify(language.t("notification.session.error.title"), description, href)
+      }
+    })
+  }
+
+  const unsub = serverSDK().event.listen((e) => {
+    const event = e.details
+    if (event.type !== "session.idle" && event.type !== "session.error") return
+
+    const directory = e.name
+    const time = Date.now()
+    if (event.type === "session.idle") {
+      handleSessionIdle(directory, event, time)
+      return
+    }
+    handleSessionError(directory, event, time)
+  })
+  onCleanup(() => {
+    meta.disposed = true
+    unsub()
+  })
+
+  return {
+    ready,
+    session: {
+      all(session: string) {
+        return index.session.all[session] ?? empty
+      },
+      unseen(session: string) {
+        return index.session.unseen[session] ?? empty
+      },
+      unseenCount(session: string) {
+        return index.session.unseenCount[session] ?? 0
+      },
+      unseenHasError(session: string) {
+        return index.session.unseenHasError[session] ?? false
+      },
+      markViewed(session: string) {
+        const unseen = index.session.unseen[session] ?? empty
+        if (!unseen.length) return
+
+        const projects = [
+          ...new Set(unseen.flatMap((notification) => (notification.directory ? [notification.directory] : []))),
+        ]
+        batch(() => {
+          setStore("list", (n) => n.session === session && !n.viewed, "viewed", true)
+          updateUnseen("session", session, [])
+          projects.forEach((directory) => {
+            const next = (index.project.unseen[directory] ?? empty).filter(
+              (notification) => notification.session !== session,
+            )
+            updateUnseen("project", directory, next)
+          })
+        })
+      },
+    },
+    project: {
+      all(directory: string) {
+        return index.project.all[directory] ?? empty
+      },
+      unseen(directory: string) {
+        return index.project.unseen[directory] ?? empty
+      },
+      unseenCount(directory: string) {
+        return index.project.unseenCount[directory] ?? 0
+      },
+      unseenHasError(directory: string) {
+        return index.project.unseenHasError[directory] ?? false
+      },
+      markViewed(directory: string) {
+        const unseen = index.project.unseen[directory] ?? empty
+        if (!unseen.length) return
+
+        const sessions = [
+          ...new Set(unseen.flatMap((notification) => (notification.session ? [notification.session] : []))),
+        ]
+        batch(() => {
+          setStore("list", (n) => n.directory === directory && !n.viewed, "viewed", true)
+          updateUnseen("project", directory, [])
+          sessions.forEach((session) => {
+            const next = (index.session.unseen[session] ?? empty).filter(
+              (notification) => notification.directory !== directory,
+            )
+            updateUnseen("session", session, next)
+          })
+        })
+      },
+    },
+  }
+}
@@ -64,6 +64,9 @@ type PlatformBase = {
  /** Storage mechanism, defaults to localStorage */
  storage?: (name?: string) => SyncStorage | AsyncStorage

+  /** Stable platform window identity for window-scoped persistence */
+  windowID?: string
+
  /** Application-global desktop updater */
  updater?: UpdaterPlatform

@@ -12,6 +12,7 @@ import { useTabs, type Tab } from "./tabs"
 import { ServerConnection } from "./server"
 import { requireServerKey } from "@/utils/session-route"
 import { useSettings } from "./settings"
+import type { FilePartSource } from "@opencode-ai/sdk/v2/client"

 interface PartBase {
  content: string
@@ -27,6 +28,10 @@ export interface FileAttachmentPart extends PartBase {
  type: "file"
  path: string
  selection?: FileSelection
+  mime?: string
+  filename?: string
+  url?: string
+  source?: FilePartSource
 }

 export interface AgentPart extends PartBase {
@@ -73,7 +78,13 @@ function isPartEqual(partA: ContentPart, partB: ContentPart) {
    case "text":
      return partB.type === "text" && partA.content === partB.content
    case "file":
-      return partB.type === "file" && partA.path === partB.path && isSelectionEqual(partA.selection, partB.selection)
+      return (
+        partB.type === "file" &&
+        partA.path === partB.path &&
+        partA.mime === partB.mime &&
+        partA.filename === partB.filename &&
+        isSelectionEqual(partA.selection, partB.selection)
+      )
    case "agent":
      return partB.type === "agent" && partA.name === partB.name
    case "image":
@@ -1,5 +1,5 @@
 import { describe, expect, test } from "bun:test"
-import { coalesceServerEvents, resumeStreamAfterPageShow } from "./server-sdk"
+import { coalesceServerEvents, enqueueServerEvent, resumeStreamAfterPageShow } from "./server-sdk"
 import type { Event } from "@opencode-ai/sdk/v2/client"

 describe("resumeStreamAfterPageShow", () => {
@@ -15,19 +15,23 @@ describe("resumeStreamAfterPageShow", () => {
 })

 describe("coalesceServerEvents", () => {
-  const delta = (value: string, field = "text") => ({
+  const delta = (value: string, field = "text", partID = "part") => ({
    directory: "/repo",
    payload: {
      type: "message.part.delta",
-      properties: { messageID: "msg", partID: "part", field, delta: value },
+      properties: { messageID: "msg", partID, field, delta: value },
    } as Event,
  })

  test("merges adjacent deltas for the same field", () => {
-    const result = coalesceServerEvents([delta("hello "), delta("world")])
+    const first = delta("hello ")
+    const second = delta("world")
+    first.payload.id = "first"
+    second.payload.id = "second"
+    const result = coalesceServerEvents([first, second])

    expect(result).toHaveLength(1)
-    expect(result[0]?.payload).toMatchObject({ properties: { delta: "hello world" } })
+    expect(result[0]?.payload).toMatchObject({ id: "second", properties: { delta: "hello world" } })
  })

  test("preserves event boundaries and distinct fields", () => {
@@ -45,9 +49,112 @@ describe("coalesceServerEvents", () => {
    ])
  })

-  test("drops stale deltas", () => {
-    const result = coalesceServerEvents([delta("stale")], new Set(["/repo:msg:part"]))
+  test("preserves event ID order across interleaved deltas", () => {
+    const first = delta("a")
+    const other = delta("b", "text", "other")
+    const last = delta("c")
+    first.payload.id = "1"
+    other.payload.id = "2"
+    last.payload.id = "3"

-    expect(result).toEqual([])
+    const result = coalesceServerEvents([first, other, last])
+
+    expect(result.map((event) => event.payload.id)).toEqual(["1", "2", "3"])
+  })
+})
+
+describe("enqueueServerEvent", () => {
+  const partUpdated = (text: string) =>
+    ({
+      type: "message.part.updated",
+      properties: {
+        sessionID: "session",
+        part: { id: "part", sessionID: "session", messageID: "message", type: "text", text },
+      },
+    }) as Event
+
+  test("preserves part updates across message remove and re-add barriers", () => {
+    const events: Array<{ directory: string; payload: Event }> = []
+    const enqueue = (payload: Event) => enqueueServerEvent(events, { directory: "/repo", payload })
+
+    enqueue(partUpdated("old"))
+    enqueue({ type: "message.removed", properties: { sessionID: "session", messageID: "message" } } as Event)
+    enqueue({
+      type: "message.updated",
+      properties: {
+        sessionID: "session",
+        info: {
+          id: "message",
+          sessionID: "session",
+          role: "user",
+          time: { created: 1 },
+          agent: "build",
+          model: { providerID: "provider", modelID: "model" },
+        },
+      },
+    } as Event)
+    enqueue(partUpdated("new"))
+
+    expect(events.map((event) => event.payload.type)).toEqual([
+      "message.part.updated",
+      "message.removed",
+      "message.updated",
+      "message.part.updated",
+    ])
+  })
+
+  test("preserves deltas after a replacement snapshot", () => {
+    const events: Array<{ directory: string; payload: Event }> = []
+    const enqueue = (payload: Event) => enqueueServerEvent(events, { directory: "/repo", payload })
+
+    enqueue(partUpdated("a"))
+    enqueue(partUpdated("ab"))
+    enqueue({
+      type: "message.part.delta",
+      properties: { sessionID: "session", messageID: "message", partID: "part", field: "text", delta: "c" },
+    } as Event)
+
+    const result = coalesceServerEvents(events)
+    expect(result.map((event) => event.payload.type)).toEqual(["message.part.updated", "message.part.delta"])
+    expect(result[0]?.payload).toMatchObject({ properties: { part: { text: "ab" } } })
+    expect(result[1]?.payload).toMatchObject({ properties: { delta: "c" } })
+  })
+
+  test("preserves updates after session deletion", () => {
+    const events: Array<{ directory: string; payload: Event }> = []
+    const enqueue = (payload: Event) => enqueueServerEvent(events, { directory: "/repo", payload })
+
+    enqueue(partUpdated("old"))
+    enqueue({
+      type: "session.deleted",
+      properties: { sessionID: "session", info: { id: "session" } },
+    } as Event)
+    enqueue(partUpdated("new"))
+
+    expect(events.map((event) => event.payload.type)).toEqual([
+      "message.part.updated",
+      "session.deleted",
+      "message.part.updated",
+    ])
+  })
+
+  test("does not coalesce edge-triggered session statuses", () => {
+    const events: Array<{ directory: string; payload: Event }> = []
+    const enqueue = (status: "retry" | "busy") =>
+      enqueueServerEvent(events, {
+        directory: "/repo",
+        payload: {
+          type: "session.status",
+          properties: {
+            sessionID: "session",
+            status: status === "retry" ? { type: "retry", attempt: 1, message: "retry", next: 1 } : { type: "busy" },
+          },
+        } as Event,
+      })
+
+    enqueue("retry")
+    enqueue("busy")
+
+    expect(events).toHaveLength(2)
  })
 })
@@ -17,34 +17,56 @@ const isAbortError = (error: unknown) =>
 const isStreamClosed = (error: unknown, signal?: AbortSignal) => isAbortError(error) || signal?.aborted === true
 type QueuedServerEvent = { directory: string; payload: Event }

-const deltaKey = (directory: string, messageID: string, partID: string) => `${directory}:${messageID}:${partID}`
+const coalescedKey = (event: QueuedServerEvent) => {
+  if (event.payload.type === "lsp.updated") return `lsp.updated:${event.directory}`
+  if (event.payload.type === "message.part.updated") {
+    const part = event.payload.properties.part
+    return `message.part.updated:${event.directory}:${part.messageID}:${part.id}`
+  }
+  return undefined
+}

-export function coalesceServerEvents(events: QueuedServerEvent[], stale?: Set<string>) {
+export function enqueueServerEvent(queue: QueuedServerEvent[], event: QueuedServerEvent) {
+  const key = coalescedKey(event)
+  const previous = queue[queue.length - 1]
+  if (key && previous && coalescedKey(previous) === key) {
+    queue[queue.length - 1] = event
+    return false
+  }
+  queue.push(event)
+  return true
+}
+
+export function coalesceServerEvents(events: QueuedServerEvent[]) {
  const output: QueuedServerEvent[] = []
-  const deltas = new Map<string, number>()
  events.forEach((event) => {
-    if (stale && event.payload.type === "message.part.delta") {
-      const props = event.payload.properties
-      if (stale.has(deltaKey(event.directory, props.messageID, props.partID))) return
-    }
    if (event.payload.type !== "message.part.delta") {
-      deltas.clear()
      output.push(event)
      return
    }
    const props = event.payload.properties
-    const id = `${deltaKey(event.directory, props.messageID, props.partID)}:${props.field}`
-    const index = deltas.get(id)
-    const existing = index === undefined ? undefined : output[index]
-    if (!existing || existing.payload.type !== "message.part.delta") {
-      deltas.set(id, output.length)
+    const previous = output[output.length - 1]
+    if (
+      !previous ||
+      previous.payload.type !== "message.part.delta" ||
+      previous.directory !== event.directory ||
+      previous.payload.properties.messageID !== props.messageID ||
+      previous.payload.properties.partID !== props.partID ||
+      previous.payload.properties.field !== props.field
+    ) {
      output.push({
        directory: event.directory,
        payload: { ...event.payload, properties: { ...props } },
      })
      return
    }
-    existing.payload.properties.delta += props.delta
+    output[output.length - 1] = {
+      directory: event.directory,
+      payload: {
+        ...event.payload,
+        properties: { ...props, delta: previous.payload.properties.delta + props.delta },
+      },
+    }
  })
  return output
 }
@@ -85,20 +107,9 @@ function createServerSdkContextBase(server: ServerConnection.Any, scope: ServerS

  let queue: Queued[] = []
  let buffer: Queued[] = []
-  const coalesced = new Map<string, number>()
-  const staleDeltas = new Set<string>()
  let timer: ReturnType<typeof setTimeout> | undefined
  let last = 0

-  const key = (directory: string, payload: Event) => {
-    if (payload.type === "session.status") return `session.status:${directory}:${payload.properties.sessionID}`
-    if (payload.type === "lsp.updated") return `lsp.updated:${directory}`
-    if (payload.type === "message.part.updated") {
-      const part = payload.properties.part
-      return `message.part.updated:${directory}:${part.messageID}:${part.id}`
-    }
-  }
-
  const flush = () => {
    if (timer) clearTimeout(timer)
    timer = undefined
@@ -106,15 +117,12 @@ function createServerSdkContextBase(server: ServerConnection.Any, scope: ServerS
    if (queue.length === 0) return

    const events = queue
-    const skip = staleDeltas.size > 0 ? new Set(staleDeltas) : undefined
    queue = buffer
    buffer = events
    queue.length = 0
-    coalesced.clear()
-    staleDeltas.clear()

    last = Date.now()
-    const output = coalesceServerEvents(events, skip)
+    const output = coalesceServerEvents(events)
    batch(() => {
      output.forEach((event) => emitter.emit(event.directory, event.payload))
    })
@@ -184,29 +192,12 @@ function createServerSdkContextBase(server: ServerConnection.Any, scope: ServerS
          for await (const event of events.stream) {
            resetHeartbeat()
            streamErrorLogged = false
-            const directory = event.directory ?? "global"
-            if (event.payload.type === "sync") {
-              continue
+            if (event.payload.type !== "sync") {
+              const directory = event.directory ?? "global"
+              const payload = event.payload as Event
+              if (enqueueServerEvent(queue, { directory, payload })) schedule()
            }

-            const payload = event.payload as Event
-
-            const k = key(directory, payload)
-            if (k) {
-              const i = coalesced.get(k)
-              if (i !== undefined) {
-                queue[i] = { directory, payload }
-                if (payload.type === "message.part.updated") {
-                  const part = payload.properties.part
-                  staleDeltas.add(deltaKey(directory, part.messageID, part.id))
-                }
-                continue
-              }
-              coalesced.set(k, queue.length)
-            }
-            queue.push({ directory, payload })
-            schedule()
-
            if (Date.now() - yielded < STREAM_YIELD_MS) continue
            yielded = Date.now()
            await wait(0)
@@ -1,5 +1,6 @@
 import { describe, expect, test } from "bun:test"
-import type { OpencodeClient, Session } from "@opencode-ai/sdk/v2/client"
+import type { retry } from "@opencode-ai/core/util/retry"
+import type { Message, OpencodeClient, Part, Session } from "@opencode-ai/sdk/v2/client"
 import { createServerSession } from "./server-session"

 const session = (id: string, parentID?: string): Session => ({
@@ -13,6 +14,74 @@ const session = (id: string, parentID?: string): Session => ({
  time: { created: 1, updated: 1 },
 })

+type UserMessage = Extract<Message, { role: "user" }>
+type TextPart = Extract<Part, { type: "text" }>
+type MessageResponse = {
+  data: { info: Message; parts: Part[] }[]
+  response: { headers: Headers }
+}
+
+const userMessage = (id: string, input: Partial<UserMessage> = {}): UserMessage => ({
+  id,
+  sessionID: "child",
+  role: "user",
+  time: { created: 1 },
+  agent: "build",
+  model: { providerID: "provider", modelID: "model" },
+  ...input,
+})
+
+const textPart = (messageID: string, input: Partial<TextPart> = {}): TextPart => ({
+  id: "part",
+  sessionID: "child",
+  messageID,
+  type: "text",
+  text: "text",
+  ...input,
+})
+
+const response = (data: MessageResponse["data"] = [], cursor?: string): MessageResponse => ({
+  data,
+  response: { headers: new Headers(cursor ? { "x-next-cursor": cursor } : undefined) },
+})
+
+const deferredResponse = () => Promise.withResolvers<MessageResponse>()
+
+function messageClient(...responses: Array<MessageResponse | Promise<MessageResponse>>) {
+  let index = 0
+  const requests: unknown[] = []
+  const waiting = new Map<number, () => void>()
+  const client = {
+    session: {
+      get: async () => ({ data: session("child", "root") }),
+      messages: (input: unknown) => {
+        requests.push(input)
+        waiting.get(requests.length)?.()
+        waiting.delete(requests.length)
+        return responses[index++]
+      },
+    },
+  } as unknown as OpencodeClient
+  return Object.assign(client, {
+    requests,
+    requested(count: number) {
+      if (requests.length >= count) return Promise.resolve()
+      return new Promise<void>((resolve) => waiting.set(count, resolve))
+    },
+  })
+}
+
+const retryImmediately: typeof retry = async (task, options = {}) => {
+  const attempts = options.attempts ?? 3
+  for (let attempt = 0; ; attempt++) {
+    try {
+      return await task()
+    } catch (error) {
+      if (attempt === attempts - 1) throw error
+    }
+  }
+}
+
 function setup(sessions: Record<string, Session>) {
  const get: unknown[] = []
  const messages: unknown[] = []
@@ -25,7 +94,7 @@ function setup(sessions: Record<string, Session>) {
      },
      messages: async (input: unknown) => {
        messages.push(input)
-        return { data: [], response: { headers: new Headers() } }
+        return response()
      },
      diff: async () => ({ data: [] }),
      todo: async () => ({ data: [] }),
@@ -55,13 +124,971 @@ describe("server session", () => {
    expect(ctx.store.data.message.root).toEqual([])
  })

+  test("merges live events into the initial page", async () => {
+    const pending = deferredResponse()
+    const user = userMessage("message-1")
+    const live = userMessage("message-2", { time: { created: 2 } })
+    const livePart = textPart(live.id, { text: "live" })
+    const store = createServerSession(messageClient(pending.promise))
+    const loading = store.sync("child")
+
+    store.apply({ type: "message.updated", properties: { info: live } })
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part: livePart, time: 2 } })
+    pending.resolve(response([{ info: user, parts: [] }]))
+    await loading
+
+    expect(store.data.message.child).toEqual([user, live])
+    expect(store.data.part[live.id]).toEqual([livePart])
+  })
+
+  test("preserves same-ID live updates over the initial page", async () => {
+    const pending = deferredResponse()
+    const fetched = userMessage("message")
+    const fetchedPart = textPart(fetched.id, { text: "fetched" })
+    const live = { ...fetched, time: { created: 2 } }
+    const livePart = { ...fetchedPart, text: "live" }
+    const store = createServerSession(messageClient(pending.promise))
+    const loading = store.sync("child")
+
+    store.apply({ type: "message.updated", properties: { info: live } })
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part: livePart, time: 2 } })
+    pending.resolve(response([{ info: fetched, parts: [fetchedPart] }]))
+    await loading
+
+    expect(store.data.message.child).toEqual([live])
+    expect(store.data.part[live.id]).toEqual([livePart])
+  })
+
+  test("preserves removals received during the initial load", async () => {
+    const pending = deferredResponse()
+    const removed = userMessage("message-1")
+    const kept = { ...removed, id: "message-2" }
+    const part = textPart(kept.id, { text: "removed" })
+    const store = createServerSession(messageClient(pending.promise))
+    const loading = store.sync("child")
+
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: removed.id } })
+    store.apply({
+      type: "message.part.removed",
+      properties: { sessionID: "child", messageID: kept.id, partID: part.id },
+    })
+    pending.resolve(
+      response([
+        { info: removed, parts: [] },
+        { info: kept, parts: [part] },
+      ]),
+    )
+    await loading
+
+    expect(store.data.message.child).toEqual([kept])
+    expect(store.data.part[kept.id]).toBeUndefined()
+  })
+
+  test("keeps removal tracking isolated across load generations", async () => {
+    const firstResponse = deferredResponse()
+    const secondResponse = deferredResponse()
+    const message = userMessage("message")
+    const store = createServerSession(messageClient(firstResponse.promise, secondResponse.promise))
+    const first = store.sync("child")
+
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+    store.apply({
+      type: "session.deleted",
+      properties: { sessionID: "child", info: session("child", "root") },
+    })
+    const second = store.sync("child")
+
+    firstResponse.resolve(response())
+    await first
+    secondResponse.resolve(response([{ info: message, parts: [] }]))
+    await second
+
+    expect(store.data.message.child).toEqual([message])
+  })
+
+  test("tracks removals in a replacement load generation", async () => {
+    const firstResponse = deferredResponse()
+    const secondResponse = deferredResponse()
+    const message = userMessage("message")
+    const store = createServerSession(messageClient(firstResponse.promise, secondResponse.promise))
+    const first = store.sync("child")
+    store.apply({
+      type: "session.deleted",
+      properties: { sessionID: "child", info: session("child", "root") },
+    })
+    const second = store.sync("child")
+
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+    firstResponse.resolve(response())
+    await first
+    secondResponse.resolve(response([{ info: message, parts: [] }]))
+    await second
+
+    expect(store.data.message.child).toEqual([])
+  })
+
+  test("preserves remove then re-add when a refresh omits the message", async () => {
+    const pending = deferredResponse()
+    const message = userMessage("message")
+    const store = createServerSession(messageClient(response([{ info: message, parts: [] }]), pending.promise))
+    await store.sync("child")
+    const refreshing = store.sync("child", { force: true })
+
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+    store.apply({ type: "message.updated", properties: { info: message } })
+    pending.resolve(response())
+    await refreshing
+
+    expect(store.data.message.child).toEqual([message])
+  })
+
+  test("preserves a re-added message without restoring removed parts", async () => {
+    const pending = deferredResponse()
+    const message = userMessage("message")
+    const part = textPart(message.id, { text: "stale" })
+    const store = createServerSession(messageClient(response([{ info: message, parts: [] }]), pending.promise))
+    await store.sync("child")
+    const refreshing = store.sync("child", { force: true })
+
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+    store.apply({ type: "message.updated", properties: { info: message } })
+    pending.resolve(response([{ info: message, parts: [part] }]))
+    await refreshing
+
+    expect(store.data.message.child).toEqual([message])
+    expect(store.data.part[message.id]).toBeUndefined()
+  })
+
+  test("preserves optimistic parts re-added after removal during a refresh", async () => {
+    const pending = deferredResponse()
+    const message = userMessage("message")
+    const stale = textPart(message.id, { id: "stale", text: "stale" })
+    const part = textPart(message.id, { id: "optimistic", text: "optimistic" })
+    const store = createServerSession(
+      messageClient(response([{ info: message, parts: [] }]), pending.promise, response()),
+    )
+    await store.sync("child")
+    const refreshing = store.sync("child", { force: true })
+
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+    store.optimistic.add({ sessionID: "child", message, parts: [part] })
+    pending.resolve(response([{ info: message, parts: [stale] }]))
+    await refreshing
+
+    expect(store.data.message.child).toEqual([message])
+    expect(store.data.part[message.id]).toEqual([part])
+
+    await store.sync("child", { force: true })
+    expect(store.data.message.child).toEqual([message])
+    expect(store.data.part[message.id]).toEqual([part])
+  })
+
+  test("drops stale event content omitted by a complete initial page", async () => {
+    const stale = userMessage("stale")
+    const store = createServerSession(messageClient(response()))
+    store.apply({ type: "message.updated", properties: { info: stale } })
+
+    await store.sync("child")
+
+    expect(store.data.message.child).toEqual([])
+  })
+
+  test("preserves event content outside an incomplete initial page", async () => {
+    const live = userMessage("message-1")
+    const fetched = userMessage("message-2", { time: { created: 2 } })
+    const store = createServerSession(messageClient(response([{ info: fetched, parts: [] }], "older")))
+    store.apply({ type: "message.updated", properties: { info: live } })
+
+    await store.sync("child")
+
+    expect(store.data.message.child).toEqual([live, fetched])
+  })
+
+  test("does not restore removed optimistic content on refresh", async () => {
+    const message = userMessage("message")
+    const part = textPart(message.id, { text: "removed" })
+    const kept = { ...message, id: "kept" }
+    const keptPart = { ...part, id: "kept-part", messageID: kept.id }
+    const store = createServerSession(messageClient(response([{ info: kept, parts: [] }])))
+    store.optimistic.add({ sessionID: "child", message, parts: [part] })
+    store.optimistic.add({ sessionID: "child", message: kept, parts: [keptPart] })
+
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+    store.apply({
+      type: "message.part.removed",
+      properties: { sessionID: "child", messageID: kept.id, partID: keptPart.id },
+    })
+    await store.sync("child", { force: true })
+
+    expect(store.data.message.child).toEqual([kept])
+    expect(store.data.part[message.id]).toBeUndefined()
+    expect(store.data.part[kept.id]).toBeUndefined()
+  })
+
+  test("replaces confirmed optimistic content with the initial page", async () => {
+    const optimistic = userMessage("message")
+    const fetched = { ...optimistic, time: { created: 2 } }
+    const store = createServerSession(messageClient(response([{ info: fetched, parts: [] }])))
+    store.optimistic.add({ sessionID: "child", message: optimistic, parts: [] })
+
+    await store.sync("child")
+
+    expect(store.data.message.child).toEqual([fetched])
+  })
+
+  test("replaces a confirmed optimistic part with fetched content", async () => {
+    const pending = deferredResponse()
+    const message = userMessage("message")
+    const optimistic = textPart(message.id, { text: "optimistic" })
+    const fetched = { ...optimistic, text: "fetched" }
+    const store = createServerSession(messageClient(pending.promise))
+    const loading = store.sync("child")
+
+    store.optimistic.add({ sessionID: "child", message, parts: [optimistic] })
+    pending.resolve(response([{ info: message, parts: [fetched] }]))
+    await loading
+
+    expect(store.data.part[message.id]).toEqual([fetched])
+  })
+
+  test("rolls back only unconfirmed optimistic parts", async () => {
+    const pending = deferredResponse()
+    const message = userMessage("message")
+    const confirmed = textPart(message.id, { id: "confirmed", text: "confirmed" })
+    const pendingPart = textPart(message.id, { id: "pending", text: "pending" })
+    const store = createServerSession(messageClient(pending.promise))
+    const loading = store.sync("child")
+    store.optimistic.add({ sessionID: "child", message, parts: [confirmed, pendingPart] })
+
+    pending.resolve(response([{ info: message, parts: [confirmed] }]))
+    await loading
+    store.optimistic.remove({ sessionID: "child", messageID: message.id })
+
+    expect(store.data.message.child).toEqual([message])
+    expect(store.data.part[message.id]).toEqual([confirmed])
+  })
+
+  test("updates confirmed optimistic parts from later pages", async () => {
+    const message = userMessage("message")
+    const confirmed = textPart(message.id, { id: "confirmed", text: "first" })
+    const updated = { ...confirmed, text: "updated" }
+    const pendingPart = textPart(message.id, { id: "pending", text: "pending" })
+    const store = createServerSession(
+      messageClient(response([{ info: message, parts: [confirmed] }]), response([{ info: message, parts: [updated] }])),
+    )
+    store.optimistic.add({ sessionID: "child", message, parts: [confirmed, pendingPart] })
+    await store.sync("child")
+
+    await store.sync("child", { force: true })
+    store.optimistic.remove({ sessionID: "child", messageID: message.id })
+
+    expect(store.data.part[message.id]).toEqual([updated])
+  })
+
+  test("does not restore a confirmed optimistic part after its removal event", async () => {
+    const message = userMessage("message")
+    const confirmed = textPart(message.id, { id: "confirmed", text: "confirmed" })
+    const pendingPart = textPart(message.id, { id: "pending", text: "pending" })
+    const store = createServerSession(
+      messageClient(response([{ info: message, parts: [confirmed] }]), response([{ info: message, parts: [] }])),
+    )
+    store.optimistic.add({ sessionID: "child", message, parts: [confirmed, pendingPart] })
+    await store.sync("child")
+    store.apply({
+      type: "message.part.removed",
+      properties: { sessionID: "child", messageID: message.id, partID: confirmed.id },
+    })
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.part[message.id]).toEqual([pendingPart])
+  })
+
+  test("clears delta buffers when removing optimistic content", () => {
+    const message = userMessage("message")
+    const part = textPart(message.id, { text: "optimistic" })
+    const store = setup({ child: session("child") }).store
+    store.optimistic.add({ sessionID: "child", message, parts: [part] })
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: part.id, field: "text", delta: " delta" },
+    })
+
+    store.optimistic.remove({ sessionID: "child", messageID: message.id })
+
+    expect(store.data.part[message.id]).toBeUndefined()
+    expect(store.data.part_text_accum_delta[part.id]).toBeUndefined()
+  })
+
+  test("does not remove content confirmed by a message event", () => {
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const store = setup({ child: session("child") }).store
+    store.optimistic.add({ sessionID: "child", message, parts: [part] })
+    store.apply({ type: "message.updated", properties: { sessionID: "child", info: message } })
+
+    store.optimistic.remove({ sessionID: "child", messageID: message.id })
+
+    expect(store.data.message.child).toEqual([message])
+    expect(store.data.part[message.id]).toBeUndefined()
+  })
+
+  test("does not remove parts confirmed by part events", () => {
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const store = setup({ child: session("child") }).store
+    store.optimistic.add({ sessionID: "child", message, parts: [part] })
+    store.apply({ type: "message.updated", properties: { sessionID: "child", info: message } })
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part, time: 2 } })
+
+    store.optimistic.remove({ sessionID: "child", messageID: message.id })
+
+    expect(store.data.message.child).toEqual([message])
+    expect(store.data.part[message.id]).toEqual([part])
+  })
+
+  test("treats a part event as confirmation when it precedes the message event", () => {
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const store = setup({ child: session("child") }).store
+    store.optimistic.add({ sessionID: "child", message, parts: [part] })
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part, time: 2 } })
+
+    store.optimistic.remove({ sessionID: "child", messageID: message.id })
+
+    expect(store.data.message.child).toEqual([message])
+    expect(store.data.part[message.id]).toEqual([part])
+  })
+
+  test("clears stale parts when the initial page has none", async () => {
+    const pending = deferredResponse()
+    const message = userMessage("message")
+    const part = textPart(message.id, { text: "stale" })
+    const store = createServerSession(messageClient(pending.promise))
+    store.apply({ type: "message.updated", properties: { info: message } })
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part, time: 1 } })
+    const loading = store.sync("child")
+
+    pending.resolve(response([{ info: message, parts: [] }]))
+    await loading
+
+    expect(store.data.part[message.id]).toBeUndefined()
+  })
+
+  test("clears delta buffers for parts omitted by the initial page", async () => {
+    const pending = deferredResponse()
+    const message = userMessage("message")
+    const kept = textPart(message.id, { id: "part-1", text: "kept" })
+    const removed: Part = { ...kept, id: "part-2", text: "removed" }
+    const store = createServerSession(messageClient(pending.promise))
+    store.apply({ type: "message.updated", properties: { info: message } })
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part: kept, time: 1 } })
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part: removed, time: 1 } })
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: removed.id, field: "text", delta: " delta" },
+    })
+    const loading = store.sync("child")
+
+    pending.resolve(response([{ info: message, parts: [kept] }]))
+    await loading
+
+    expect(store.data.part[message.id]).toEqual([kept])
+    expect(store.data.part_text_accum_delta[removed.id]).toBeUndefined()
+  })
+
+  test("clears a stale delta buffer when a refresh replaces its part", async () => {
+    const message = userMessage("message")
+    const stale = textPart(message.id, { text: "stale" })
+    const fetched = { ...stale, text: "fetched" }
+    const store = createServerSession(
+      messageClient(response([{ info: message, parts: [stale] }]), response([{ info: message, parts: [fetched] }])),
+    )
+    await store.sync("child")
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: stale.id, field: "text", delta: " delta" },
+    })
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.part[message.id]).toEqual([fetched])
+    expect(store.data.part_text_accum_delta[stale.id]).toBeUndefined()
+  })
+
+  test("preserves a non-durable delta received before refresh", async () => {
+    const message = userMessage("message")
+    const part = textPart(message.id, { text: "stale" })
+    const store = createServerSession(
+      messageClient(response([{ info: message, parts: [part] }]), response([{ info: message, parts: [{ ...part }] }])),
+    )
+    await store.sync("child")
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: part.id, field: "text", delta: " delta" },
+    })
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.part[message.id]).toEqual([{ ...part, text: "stale delta" }])
+    expect(store.data.part_text_accum_delta[part.id]).toBe("stale delta")
+  })
+
+  test("accepts fetched text that intentionally replaces an accumulated prefix", async () => {
+    const message = userMessage("message")
+    const part = textPart(message.id, { text: "abc" })
+    const fetched = { ...part, text: "ab" }
+    const store = createServerSession(
+      messageClient(response([{ info: message, parts: [part] }]), response([{ info: message, parts: [fetched] }])),
+    )
+    await store.sync("child")
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: part.id, field: "text", delta: "def" },
+    })
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.part[message.id]).toEqual([fetched])
+    expect(store.data.part_text_accum_delta[part.id]).toBeUndefined()
+  })
+
+  test("preserves an unpersisted delta suffix after partial server catch-up", async () => {
+    const message = userMessage("message")
+    const part = textPart(message.id, { text: "a" })
+    const fetched = { ...part, text: "ab" }
+    const store = createServerSession(
+      messageClient(response([{ info: message, parts: [part] }]), response([{ info: message, parts: [fetched] }])),
+    )
+    await store.sync("child")
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: part.id, field: "text", delta: "bc" },
+    })
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.part[message.id]).toEqual([{ ...part, text: "abc" }])
+    expect(store.data.part_text_accum_delta[part.id]).toBe("abc")
+  })
+
+  test("clears delta state after exact server catch-up", async () => {
+    const message = userMessage("message")
+    const part = textPart(message.id, { text: "a" })
+    const fetched = { ...part, text: "ab" }
+    const store = createServerSession(
+      messageClient(response([{ info: message, parts: [part] }]), response([{ info: message, parts: [fetched] }])),
+    )
+    await store.sync("child")
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: part.id, field: "text", delta: "b" },
+    })
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.part[message.id]).toEqual([fetched])
+    expect(store.data.part_text_accum_delta[part.id]).toBeUndefined()
+  })
+
+  test("uses the successful retry response over events from a failed attempt", async () => {
+    const failed = Promise.withResolvers<MessageResponse>()
+    const retried = Promise.withResolvers<MessageResponse>()
+    const message = userMessage("message")
+    const stale = textPart(message.id, { text: "stale" })
+    const intermediate = { ...stale, text: "intermediate" }
+    const fetched = { ...stale, text: "fetched" }
+    const client = messageClient(failed.promise, retried.promise)
+    const store = createServerSession(client, { retry: retryImmediately })
+    store.apply({ type: "message.updated", properties: { info: message } })
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part: stale, time: 1 } })
+    const loading = store.sync("child")
+
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part: intermediate, time: 2 } })
+    failed.reject(new Error("failed to fetch"))
+    await client.requested(2)
+    retried.resolve(response([{ info: message, parts: [fetched] }]))
+    await loading
+
+    expect(store.data.part[message.id]).toEqual([fetched])
+  })
+
+  test("preserves non-durable deltas across message retries", async () => {
+    const failed = Promise.withResolvers<MessageResponse>()
+    const retried = Promise.withResolvers<MessageResponse>()
+    const message = userMessage("message")
+    const part = textPart(message.id, { text: "stale" })
+    const client = messageClient(failed.promise, retried.promise)
+    const store = createServerSession(client, { retry: retryImmediately })
+    store.apply({ type: "message.updated", properties: { info: message } })
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part, time: 1 } })
+    const loading = store.sync("child")
+
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: part.id, field: "text", delta: " delta" },
+    })
+    failed.reject(new Error("failed to fetch"))
+    await client.requested(2)
+    retried.resolve(response([{ info: message, parts: [part] }]))
+    await loading
+
+    expect(store.data.part[message.id]).toEqual([{ ...part, text: "stale delta" }])
+  })
+
+  test("preserves part removals across message retries", async () => {
+    const failed = Promise.withResolvers<MessageResponse>()
+    const retried = Promise.withResolvers<MessageResponse>()
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const client = messageClient(response([{ info: message, parts: [part] }]), failed.promise, retried.promise)
+    const store = createServerSession(client, { retry: retryImmediately })
+    await store.sync("child")
+    const loading = store.sync("child", { force: true })
+
+    store.apply({
+      type: "message.part.removed",
+      properties: { sessionID: "child", messageID: message.id, partID: part.id },
+    })
+    failed.reject(new Error("failed to fetch"))
+    await client.requested(3)
+    retried.resolve(response([{ info: message, parts: [part] }]))
+    await loading
+
+    expect(store.data.part[message.id]).toBeUndefined()
+  })
+
+  test("preserves message removals across message retries", async () => {
+    const failed = Promise.withResolvers<MessageResponse>()
+    const retried = Promise.withResolvers<MessageResponse>()
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const client = messageClient(response([{ info: message, parts: [part] }]), failed.promise, retried.promise)
+    const store = createServerSession(client, { retry: retryImmediately })
+    await store.sync("child")
+    const loading = store.sync("child", { force: true })
+
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+    failed.reject(new Error("failed to fetch"))
+    await client.requested(3)
+    retried.resolve(response([{ info: message, parts: [part] }]))
+    await loading
+
+    expect(store.data.message.child).toEqual([])
+    expect(store.data.part[message.id]).toBeUndefined()
+  })
+
+  test("preserves optimistic re-adds across message retries", async () => {
+    const failed = Promise.withResolvers<MessageResponse>()
+    const retried = Promise.withResolvers<MessageResponse>()
+    const message = userMessage("message")
+    const stale = textPart(message.id, { id: "stale", text: "stale" })
+    const optimistic = textPart(message.id, { id: "optimistic", text: "optimistic" })
+    const client = messageClient(response([{ info: message, parts: [stale] }]), failed.promise, retried.promise)
+    const store = createServerSession(client, { retry: retryImmediately })
+    await store.sync("child")
+    const loading = store.sync("child", { force: true })
+
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+    store.optimistic.add({ sessionID: "child", message, parts: [optimistic] })
+    failed.reject(new Error("failed to fetch"))
+    await client.requested(3)
+    retried.resolve(response([{ info: message, parts: [stale] }]))
+    await loading
+
+    expect(store.data.message.child).toEqual([message])
+    expect(store.data.part[message.id]).toEqual([optimistic])
+  })
+
+  test("accepts part omission from a successful retry after an earlier delta", async () => {
+    const failed = Promise.withResolvers<MessageResponse>()
+    const retried = Promise.withResolvers<MessageResponse>()
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const client = messageClient(response([{ info: message, parts: [part] }]), failed.promise, retried.promise)
+    const store = createServerSession(client, { retry: retryImmediately })
+    await store.sync("child")
+    const loading = store.sync("child", { force: true })
+
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: part.id, field: "text", delta: " delta" },
+    })
+    failed.reject(new Error("failed to fetch"))
+    await client.requested(3)
+    retried.resolve(response([{ info: message, parts: [] }]))
+    await loading
+
+    expect(store.data.part[message.id]).toBeUndefined()
+    expect(store.data.part_text_accum_delta[part.id]).toBeUndefined()
+  })
+
+  test("clears load-owned orphan parts when all retries fail", async () => {
+    const first = Promise.withResolvers<MessageResponse>()
+    const second = Promise.withResolvers<MessageResponse>()
+    const third = Promise.withResolvers<MessageResponse>()
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const client = messageClient(first.promise, second.promise, third.promise)
+    const store = createServerSession(client, { retry: retryImmediately })
+    const loading = store.sync("child").catch((error) => error)
+
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part, time: 2 } })
+    first.reject(new Error("failed to fetch"))
+    await client.requested(2)
+    second.reject(new Error("failed to fetch"))
+    await client.requested(3)
+    third.reject(new Error("failed to fetch"))
+    await loading
+
+    expect(store.data.part[message.id]).toBeUndefined()
+  })
+
+  test("preserves live updates during a forced refresh", async () => {
+    const pending = deferredResponse()
+    const stale = userMessage("message")
+    const stalePart = textPart(stale.id, { text: "stale" })
+    const store = createServerSession(messageClient(response([{ info: stale, parts: [stalePart] }]), pending.promise))
+    await store.sync("child")
+    const refreshing = store.sync("child", { force: true })
+    const live = { ...stale, time: { created: 2 } }
+
+    store.apply({ type: "message.updated", properties: { info: live } })
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: stale.id, partID: stalePart.id, field: "text", delta: " live" },
+    })
+    pending.resolve(response([{ info: stale, parts: [stalePart] }]))
+    await refreshing
+
+    expect(store.data.message.child).toEqual([live])
+    expect(store.data.part[stale.id]).toEqual([{ ...stalePart, text: "stale live" }])
+  })
+
+  test("keeps fetched message metadata when only a part changes", async () => {
+    const pending = deferredResponse()
+    const stale = userMessage("message")
+    const fetched = { ...stale, time: { created: 2 } }
+    const part = textPart(stale.id, { text: "stale" })
+    const store = createServerSession(messageClient(response([{ info: stale, parts: [part] }]), pending.promise))
+    await store.sync("child")
+    const refreshing = store.sync("child", { force: true })
+
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: stale.id, partID: part.id, field: "text", delta: " live" },
+    })
+    pending.resolve(response([{ info: fetched, parts: [part] }]))
+    await refreshing
+
+    expect(store.data.message.child).toEqual([fetched])
+    expect(store.data.part[stale.id]).toEqual([{ ...part, text: "stale live" }])
+  })
+
+  test("preserves a part update when a forced refresh omits its message", async () => {
+    const pending = deferredResponse()
+    const message = userMessage("message")
+    const stale = textPart(message.id, { text: "stale" })
+    const live = { ...stale, text: "live" }
+    const store = createServerSession(messageClient(response([{ info: message, parts: [stale] }]), pending.promise))
+    await store.sync("child")
+    const refreshing = store.sync("child", { force: true })
+
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part: live, time: 2 } })
+    pending.resolve(response())
+    await refreshing
+
+    expect(store.data.message.child).toEqual([message])
+    expect(store.data.part[message.id]).toEqual([live])
+  })
+
+  test("ignores a late part update after its message is removed", async () => {
+    const pending = deferredResponse()
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const store = createServerSession(messageClient(pending.promise))
+    const loading = store.sync("child")
+
+    store.apply({ type: "message.updated", properties: { info: message } })
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part, time: 2 } })
+    pending.resolve(response([{ info: message, parts: [part] }]))
+    await loading
+
+    expect(store.data.message.child).toEqual([])
+    expect(store.data.part[message.id]).toBeUndefined()
+  })
+
+  test("ignores a late part update after a completed message removal", () => {
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const store = setup({ child: session("child") }).store
+    store.apply({ type: "message.updated", properties: { info: message } })
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part, time: 2 } })
+
+    expect(store.data.part[message.id]).toBeUndefined()
+  })
+
+  test("does not restore a completed message removal from a stale refresh", async () => {
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const store = createServerSession(
+      messageClient(response([{ info: message, parts: [part] }]), response([{ info: message, parts: [part] }])),
+    )
+    await store.sync("child")
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: message.id } })
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.message.child).toEqual([])
+    expect(store.data.part[message.id]).toBeUndefined()
+  })
+
+  test("does not restore a completed part removal from a stale refresh", async () => {
+    const message = userMessage("message")
+    const part = textPart(message.id)
+    const store = createServerSession(
+      messageClient(response([{ info: message, parts: [part] }]), response([{ info: message, parts: [part] }])),
+    )
+    await store.sync("child")
+    store.apply({
+      type: "message.part.removed",
+      properties: { sessionID: "child", messageID: message.id, partID: part.id },
+    })
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.part[message.id]).toBeUndefined()
+  })
+
+  test("does not cache skipped optimistic parts", () => {
+    const message = userMessage("message")
+    const part = { id: "part", sessionID: "child", messageID: message.id, type: "step-start" as const }
+    const store = setup({ child: session("child") }).store
+
+    store.optimistic.add({ sessionID: "child", message, parts: [part] })
+
+    expect(store.data.part[message.id]).toEqual([])
+  })
+
+  test("clears stale delta buffers when replacing optimistic parts", () => {
+    const message = userMessage("message")
+    const stale = textPart(message.id, { id: "stale", text: "stale" })
+    const optimistic = textPart(message.id, { id: "optimistic", text: "optimistic" })
+    const store = setup({ child: session("child") }).store
+    store.optimistic.add({ sessionID: "child", message, parts: [stale] })
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: stale.id, field: "text", delta: " delta" },
+    })
+
+    store.optimistic.add({ sessionID: "child", message, parts: [optimistic] })
+
+    expect(store.data.part_text_accum_delta[stale.id]).toBeUndefined()
+    expect(store.data.part_text_accum_delta[optimistic.id]).toBeUndefined()
+  })
+
+  test("preserves removals during history prepend", async () => {
+    const pending = deferredResponse()
+    const latest = userMessage("message-2", { time: { created: 2 } })
+    const older = { ...latest, id: "message-1", time: { created: 1 } }
+    const store = createServerSession(messageClient(response([{ info: latest, parts: [] }], "older"), pending.promise))
+    await store.sync("child")
+    const loading = store.history.loadMore("child")
+
+    store.apply({ type: "message.removed", properties: { sessionID: "child", messageID: older.id } })
+    pending.resolve(response([{ info: older, parts: [] }]))
+    await loading
+
+    expect(store.data.message.child).toEqual([latest])
+  })
+
+  test("preserves loaded history during an incomplete refresh", async () => {
+    const older = userMessage("message-1")
+    const latest = userMessage("message-2", { time: { created: 2 } })
+    const fresh = userMessage("message-3", { time: { created: 3 } })
+    const store = createServerSession(
+      messageClient(
+        response(
+          [
+            { info: older, parts: [] },
+            { info: latest, parts: [] },
+          ],
+          "older",
+        ),
+        response(
+          [
+            { info: latest, parts: [] },
+            { info: fresh, parts: [] },
+          ],
+          "older",
+        ),
+      ),
+    )
+    await store.sync("child")
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.message.child).toEqual([older, latest, fresh])
+  })
+
+  test("drops stale recent messages omitted by an incomplete refresh", async () => {
+    const third = userMessage("message-3", { time: { created: 3 } })
+    const fourth = userMessage("message-4", { time: { created: 4 } })
+    const stale = userMessage("message-5", { time: { created: 5 } })
+    const store = createServerSession(
+      messageClient(
+        response(
+          [
+            { info: fourth, parts: [] },
+            { info: stale, parts: [] },
+          ],
+          "older",
+        ),
+        response(
+          [
+            { info: third, parts: [] },
+            { info: fourth, parts: [] },
+          ],
+          "older",
+        ),
+      ),
+    )
+    await store.sync("child")
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.message.child).toEqual([third, fourth])
+  })
+
+  test("uses message creation time for incomplete refresh boundaries", async () => {
+    const older = userMessage("msg_z", { time: { created: 1 } })
+    const boundary = userMessage("msg_m", { time: { created: 2 } })
+    const stale = userMessage("msg_a", { time: { created: 3 } })
+    const store = createServerSession(
+      messageClient(
+        response(
+          [
+            { info: older, parts: [] },
+            { info: stale, parts: [] },
+          ],
+          "older",
+        ),
+        response([{ info: boundary, parts: [] }], "older"),
+      ),
+    )
+    await store.sync("child")
+
+    await store.sync("child", { force: true })
+
+    expect(store.data.message.child).toEqual([boundary, older])
+  })
+
+  test("preserves a part update for a message being loaded from history", async () => {
+    const pending = deferredResponse()
+    const latest = userMessage("message-2", { time: { created: 2 } })
+    const older = userMessage("message-1")
+    const stale = textPart(older.id, { text: "stale" })
+    const live = { ...stale, text: "live" }
+    const store = createServerSession(messageClient(response([{ info: latest, parts: [] }], "older"), pending.promise))
+    await store.sync("child")
+    const loading = store.history.loadMore("child")
+
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part: live, time: 2 } })
+    pending.resolve(response([{ info: older, parts: [stale] }]))
+    await loading
+
+    expect(store.data.part[older.id]).toEqual([live])
+  })
+
+  test("does not clear newer orphan parts after terminal history prepend", async () => {
+    const pending = deferredResponse()
+    const latest = userMessage("message-2", { time: { created: 2 } })
+    const older = userMessage("message-1")
+    const newer = userMessage("message-3", { time: { created: 3 } })
+    const part = textPart(newer.id, { text: "live" })
+    const store = createServerSession(messageClient(response([{ info: latest, parts: [] }], "older"), pending.promise))
+    await store.sync("child")
+    const loading = store.history.loadMore("child")
+
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part, time: 3 } })
+    pending.resolve(response([{ info: older, parts: [] }]))
+    await loading
+    store.apply({ type: "message.updated", properties: { sessionID: "child", info: newer } })
+
+    expect(store.data.part[newer.id]).toEqual([part])
+  })
+
+  test("accepts an authoritative history part after an earlier unknown-parent update", async () => {
+    const pending = deferredResponse()
+    const history = deferredResponse()
+    const latest = userMessage("message-2", { time: { created: 2 } })
+    const older = userMessage("message-1")
+    const part = textPart(older.id, { text: "live" })
+    const store = createServerSession(messageClient(pending.promise, history.promise))
+    const loading = store.sync("child")
+
+    store.apply({ type: "message.part.updated", properties: { sessionID: "child", part, time: 2 } })
+    pending.resolve(response([{ info: latest, parts: [] }], "older"))
+    await loading
+
+    expect(store.data.part[older.id]).toEqual([part])
+
+    const loadingHistory = store.history.loadMore("child")
+    history.resolve(response([{ info: older, parts: [{ ...part, text: "stale" }] }]))
+    await loadingHistory
+
+    expect(store.data.part[older.id]).toEqual([{ ...part, text: "stale" }])
+  })
+
+  test("preserves an unknown-parent part removal across pages", async () => {
+    const initial = deferredResponse()
+    const history = deferredResponse()
+    const latest = userMessage("message-2", { time: { created: 2 } })
+    const older = userMessage("message-1")
+    const part = textPart(older.id)
+    const store = createServerSession(messageClient(initial.promise, history.promise))
+    const loading = store.sync("child")
+
+    store.apply({
+      type: "message.part.removed",
+      properties: { sessionID: "child", messageID: older.id, partID: part.id },
+    })
+    initial.resolve(response([{ info: latest, parts: [] }], "older"))
+    await loading
+    const loadingHistory = store.history.loadMore("child")
+    history.resolve(response([{ info: older, parts: [part] }]))
+    await loadingHistory
+
+    expect(store.data.part[older.id]).toBeUndefined()
+  })
+
+  test("clears orphaned parts when a refresh drops a message", async () => {
+    const message = userMessage("message")
+    const part = textPart(message.id, { text: "stale" })
+    const store = createServerSession(messageClient(response([{ info: message, parts: [part] }]), response()))
+    await store.sync("child")
+    store.apply({
+      type: "message.part.delta",
+      properties: { sessionID: "child", messageID: message.id, partID: part.id, field: "text", delta: " delta" },
+    })
+    await store.sync("child", { force: true })
+
+    expect(store.data.message.child).toEqual([])
+    expect(store.data.part[message.id]).toBeUndefined()
+    expect(store.data.part_text_accum_delta[part.id]).toBeUndefined()
+  })
+
  test("applies events without a directory store", () => {
    const ctx = setup({})
-    ctx.store.apply({ type: "session.created", properties: { info: session("root") } })
+    ctx.store.apply({ type: "session.created", properties: { sessionID: "root", info: session("root") } })
    ctx.store.apply({ type: "session.status", properties: { sessionID: "root", status: { type: "busy" } } })

    expect(ctx.store.get("root")?.directory).toBe("/repo")
    expect(ctx.store.data.session_working("root")).toBe(true)
+    expect(ctx.get).toEqual([])
  })

  test("preserves pinned session content under server-wide cache pressure", () => {
@@ -87,12 +1114,14 @@ describe("server session", () => {
    })

    for (let index = 0; index < 50; index++) {
+      ctx.store.remember(session(`session-${index}`))
      ctx.store.apply({
        type: "session.status",
-        properties: { sessionID: `session-${index}`, status: { type: "busy" } },
+        properties: { sessionID: `session-${index}`, status: { type: "idle" } },
      })
    }

    expect(ctx.store.data.message.active?.map((message) => message.id)).toEqual(["message"])
+    expect(ctx.store.data.session_status["session-0"]).toBeUndefined()
  })
 })
@@ -18,44 +18,67 @@ import { rootSession } from "@/utils/session-route"
 import { dropSessionCaches, pickSessionCacheEvictions, SESSION_CACHE_LIMIT } from "./global-sync/session-cache"

 const cmp = (a: string, b: string) => (a < b ? -1 : a > b ? 1 : 0)
+const cmpMessage = (a: Message, b: Message) => a.time.created - b.time.created || cmp(a.id, b.id)
 const SKIP_PARTS = new Set(["patch", "step-start", "step-finish"])
 const initialMessagePageSize = 2
 const historyMessagePageSize = 200
 const sessionInfoLimit = 2_048
+const emptyIDs: ReadonlySet<string> = new Set()

 type OptimisticItem = {
  message: Message
  parts: Part[]
+  confirmedParts?: Part[]
+  confirmedMessage?: boolean
 }

-const hasParts = (parts: Part[] | undefined, want: Part[]) => {
-  if (!parts) return want.length === 0
-  return want.every((part) => Binary.search(parts, part.id, (item) => item.id).found)
+type MessagePage = {
+  session: Message[]
+  part: { id: string; part: Part[] }[]
+  cursor?: string
+  complete: boolean
 }

-function mergeOptimisticPage(
-  page: { session: Message[]; part: { id: string; part: Part[] }[]; cursor?: string; complete: boolean },
-  items: OptimisticItem[],
-) {
-  if (items.length === 0) return { ...page, confirmed: [] as string[] }
+// Most markers describe the current HTTP attempt; deltaParts persists non-durable stream state across retries.
+type MessageLoadState = {
+  touchedMessages: Set<string>
+  removedMessages: Set<string>
+  retainedMessages: Set<string>
+  touchedParts: Map<string, Set<string>>
+  deltaParts: Map<string, Set<string>>
+  carriedDeltaParts: Map<string, Set<string>>
+  removedParts: Map<string, Set<string>>
+  optimisticParts: Map<string, Set<string>>
+  orphanParents: Set<string>
+  clearedMessageParts: Set<string>
+}
+
+function mergeOptimisticPage(page: MessagePage, items: OptimisticItem[]) {
+  if (items.length === 0) return { ...page, observed: [] as { messageID: string; parts: Part[] }[] }
  const session = [...page.session]
  const part = new Map(page.part.map((item) => [item.id, item.part]))
-  const confirmed: string[] = []
+  const observed: { messageID: string; parts: Part[] }[] = []
  for (const item of items) {
    const result = Binary.search(session, item.message.id, (message) => message.id)
    if (!result.found) session.splice(result.index, 0, item.message)
    const current = part.get(item.message.id)
-    if (result.found && hasParts(current, item.parts)) {
-      confirmed.push(item.message.id)
-      continue
-    }
-    part.set(item.message.id, merge(current ?? [], item.parts))
+    const confirmed = result.found
+      ? item.parts.filter((part) => Binary.search(current ?? [], part.id, (value) => value.id).found)
+      : []
+    if (result.found) observed.push({ messageID: item.message.id, parts: confirmed })
+    part.set(
+      item.message.id,
+      merge(
+        result.found ? (current ?? []) : merge(item.confirmedParts ?? [], current ?? []),
+        item.parts.filter((part) => !confirmed.includes(part)),
+      ),
+    )
  }
  return {
    ...page,
    session,
    part: [...part.entries()].sort((a, b) => cmp(a[0], b[0])).map(([id, parts]) => ({ id, part: parts })),
-    confirmed,
+    observed,
  }
 }

@@ -75,7 +98,38 @@ function merge<T extends { id: string }>(a: readonly T[], b: readonly T[]) {
  return [...items.values()].sort((x, y) => cmp(x.id, y.id))
 }

-export function createServerSession(client: OpencodeClient) {
+function reconcileFetched<T extends { id: string }>(
+  fetched: T[],
+  current: readonly T[],
+  options: {
+    touched?: ReadonlySet<string>
+    retained?: ReadonlySet<string>
+    preserveUnfetched?: boolean | ((item: T) => boolean)
+  } = {},
+) {
+  const result = new Map(fetched.map((item) => [item.id, item]))
+  const live = new Map(current.map((item) => [item.id, item]))
+  if (options.preserveUnfetched) {
+    for (const item of current) {
+      if (!result.has(item.id) && (options.preserveUnfetched === true || options.preserveUnfetched(item)))
+        result.set(item.id, item)
+    }
+  }
+  for (const id of options.retained ?? emptyIDs) {
+    if (result.has(id)) continue
+    const item = live.get(id)
+    if (item) result.set(id, item)
+  }
+  // Events observed while the request is pending are the freshest client state for those identities.
+  for (const id of options.touched ?? emptyIDs) {
+    const item = live.get(id)
+    if (item) result.set(id, item)
+    if (!item) result.delete(id)
+  }
+  return [...result.values()].sort((a, b) => cmp(a.id, b.id))
+}
+
+export function createServerSession(client: OpencodeClient, options?: { retry?: typeof retry }) {
  const [data, setData] = createStore({
    info: {} as Record<string, Session | undefined>,
    session_status: {} as Record<string, SessionStatus>,
@@ -95,10 +149,32 @@ export function createServerSession(client: OpencodeClient) {
  const inflightDiff = new Map<string, Promise<void>>()
  const inflightTodo = new Map<string, Promise<void>>()
  const optimistic = new Map<string, Map<string, OptimisticItem>>()
+  const messageLoads = new Map<string, MessageLoadState>()
+  const pendingParts = new Map<string, Map<string, Set<string>>>()
+  const orphanParts = new Map<string, Set<string>>()
+  const removedMessages = new Map<string, Set<string>>()
+  const deltaBases = new Map<string, { base: string; sessionID: string }>()
+  const deleteMessageParts = (
+    cache: { part: Record<string, Part[] | undefined>; part_text_accum_delta: Record<string, string | undefined> },
+    messageID: string,
+  ) => {
+    for (const part of cache.part[messageID] ?? []) {
+      delete cache.part_text_accum_delta[part.id]
+      deltaBases.delete(part.id)
+    }
+    delete cache.part[messageID]
+  }
  const seen = new Set<string>()
  const infoSeen = new Set<string>()
  const pinned = new Map<string, number>()
-  const generations = new Map<string, number>()
+  const generations = new Map<string, object>()
+  const generation = (sessionID: string) => {
+    const current = generations.get(sessionID)
+    if (current) return current
+    const created = {}
+    generations.set(sessionID, created)
+    return created
+  }
  const [meta, setMeta] = createStore({
    limit: {} as Record<string, number | undefined>,
    cursor: {} as Record<string, string | undefined>,
@@ -115,6 +191,11 @@ export function createServerSession(client: OpencodeClient) {
      const preserve = new Set([
        ...pinned.keys(),
        ...requests.keys(),
+        ...inflight.keys(),
+        ...inflightDiff.keys(),
+        ...inflightTodo.keys(),
+        ...messageLoads.keys(),
+        ...optimistic.keys(),
        ...Object.entries(data.permission)
          .filter(([, items]) => items.length > 0)
          .map(([sessionID]) => sessionID),
@@ -138,6 +219,7 @@ export function createServerSession(client: OpencodeClient) {
        if (!preserve.has(sessionID)) stale.push(sessionID)
      }
      stale.forEach((sessionID) => infoSeen.delete(sessionID))
+      stale.forEach((sessionID) => generations.delete(sessionID))
      setData(
        "info",
        produce((draft) => stale.forEach((sessionID) => delete draft[sessionID])),
@@ -151,21 +233,27 @@ export function createServerSession(client: OpencodeClient) {
    if (cached && !options?.force) return Promise.resolve(cached)
    const pending = requests.get(sessionID)
    if (pending) return pending
-    const generation = generations.get(sessionID) ?? 0
+    const active = generation(sessionID)
    const request = client.session.get({ sessionID }).then((result) => {
      if (!result.data) throw new Error(`Session not found: ${sessionID}`)
-      if ((generations.get(sessionID) ?? 0) !== generation) return result.data
+      if (generations.get(sessionID) !== active) return result.data
      return remember(result.data)
    })
    requests.set(sessionID, request)
-    void request.then(
-      () => {
-        if (requests.get(sessionID) === request) requests.delete(sessionID)
-      },
-      () => {
-        if (requests.get(sessionID) === request) requests.delete(sessionID)
-      },
-    )
+    const cleanup = () => {
+      if (requests.get(sessionID) === request) requests.delete(sessionID)
+      if (
+        generations.get(sessionID) === active &&
+        !data.info[sessionID] &&
+        !requests.has(sessionID) &&
+        !messageLoads.has(sessionID) &&
+        !inflight.has(sessionID) &&
+        !inflightDiff.has(sessionID) &&
+        !inflightTodo.has(sessionID)
+      )
+        generations.delete(sessionID)
+    }
+    void request.then(cleanup, cleanup)
    return request
  }

@@ -195,15 +283,121 @@ export function createServerSession(client: OpencodeClient) {
    if (items.size === 0) optimistic.delete(sessionID)
  }

+  const clearOptimisticPart = (sessionID: string, messageID: string, partID: string) => {
+    const items = optimistic.get(sessionID)
+    const item = items?.get(messageID)
+    if (!items || !item) return
+    const parts = item.parts.filter((part) => part.id !== partID)
+    const confirmedParts = item.confirmedParts?.filter((part) => part.id !== partID)
+    if (parts.length === 0) {
+      clearOptimistic(sessionID, messageID)
+      return
+    }
+    items.set(messageID, { ...item, parts, confirmedParts, confirmedMessage: true })
+  }
+
+  const confirmOptimisticPart = (sessionID: string, messageID: string, part: Part) => {
+    const items = optimistic.get(sessionID)
+    const item = items?.get(messageID)
+    if (!items || !item) return
+    const parts = item.parts.filter((value) => value.id !== part.id)
+    if (parts.length === 0) {
+      clearOptimistic(sessionID, messageID)
+      return
+    }
+    items.set(messageID, {
+      ...item,
+      parts,
+      confirmedParts: merge(item.confirmedParts ?? [], [part]),
+      confirmedMessage: true,
+    })
+  }
+
+  const confirmOptimistic = (sessionID: string, messageID: string, confirmedParts: Part[]) => {
+    const items = optimistic.get(sessionID)
+    const item = items?.get(messageID)
+    if (!items || !item) return
+    const confirmed = new Set(confirmedParts.map((part) => part.id))
+    const parts = item.parts.filter((part) => !confirmed.has(part.id))
+    if (parts.length === 0) {
+      clearOptimistic(sessionID, messageID)
+      return
+    }
+    items.set(messageID, {
+      ...item,
+      parts,
+      confirmedParts: merge(item.confirmedParts ?? [], confirmedParts),
+      confirmedMessage: true,
+    })
+  }
+
+  const trackPartChange = (sessionID: string, messageID: string, partID: string) => {
+    const load = messageLoads.get(sessionID)
+    if (!load) return
+    // A part event keeps an existing parent when the fetched page omits it without overriding fetched metadata.
+    const messages = data.message[sessionID]
+    if (messages && Binary.search(messages, messageID, (message) => message.id).found)
+      load.retainedMessages.add(messageID)
+    const parts = load.touchedParts.get(messageID)
+    if (parts) {
+      parts.add(partID)
+      return
+    }
+    load.touchedParts.set(messageID, new Set([partID]))
+  }
+
+  const resetMessageLoad = (sessionID: string, load: MessageLoadState) => {
+    load.touchedMessages.clear()
+    load.retainedMessages.clear()
+    load.touchedParts.clear()
+    load.carriedDeltaParts.clear()
+    load.clearedMessageParts.clear()
+    for (const messageID of load.removedMessages) {
+      load.touchedMessages.add(messageID)
+      load.clearedMessageParts.add(messageID)
+    }
+    for (const [messageID, parts] of load.deltaParts) {
+      load.touchedParts.set(messageID, new Set(parts))
+      load.carriedDeltaParts.set(messageID, new Set(parts))
+      const messages = data.message[sessionID]
+      if (messages && Binary.search(messages, messageID, (message) => message.id).found)
+        load.retainedMessages.add(messageID)
+    }
+    for (const [messageID, parts] of load.removedParts) {
+      const touched = load.touchedParts.get(messageID) ?? new Set<string>()
+      parts.forEach((partID) => touched.add(partID))
+      load.touchedParts.set(messageID, touched)
+      const messages = data.message[sessionID]
+      if (messages && Binary.search(messages, messageID, (message) => message.id).found)
+        load.retainedMessages.add(messageID)
+    }
+    for (const [messageID, parts] of load.optimisticParts) {
+      load.removedMessages.delete(messageID)
+      load.clearedMessageParts.add(messageID)
+      load.touchedMessages.add(messageID)
+      const touched = load.touchedParts.get(messageID) ?? new Set<string>()
+      parts.forEach((partID) => touched.add(partID))
+      load.touchedParts.set(messageID, touched)
+    }
+  }
+
  const evict = (sessionIDs: string[]) => {
    if (sessionIDs.length === 0) return
+    const evicted = new Set(sessionIDs)
+    for (const [partID, item] of deltaBases) {
+      if (evicted.has(item.sessionID)) deltaBases.delete(partID)
+    }
    sessionIDs.forEach((sessionID) => {
-      generations.set(sessionID, (generations.get(sessionID) ?? 0) + 1)
+      generations.delete(sessionID)
      clearOptimistic(sessionID)
      requests.delete(sessionID)
      inflight.delete(sessionID)
      inflightDiff.delete(sessionID)
      inflightTodo.delete(sessionID)
+      messageLoads.delete(sessionID)
+      pendingParts.delete(sessionID)
+      orphanParts.delete(sessionID)
+      removedMessages.delete(sessionID)
    })
    setData(
      produce((draft) => {
@@ -230,6 +424,7 @@ export function createServerSession(client: OpencodeClient) {
      ...inflight.keys(),
      ...inflightDiff.keys(),
      ...inflightTodo.keys(),
+      ...messageLoads.keys(),
      ...optimistic.keys(),
      ...Object.entries(data.permission)
        .filter(([, items]) => items.length > 0)
@@ -247,8 +442,11 @@ export function createServerSession(client: OpencodeClient) {
      pickSessionCacheEvictions({ seen, keep: sessionID, limit: SESSION_CACHE_LIMIT, preserve: protectedSessions() }),
    )

-  const fetchMessages = async (sessionID: string, limit: number, before?: string) => {
-    const response = await retry(() => client.session.messages({ sessionID, limit, before }))
+  const fetchMessages = async (sessionID: string, limit: number, before?: string, onAttempt?: () => void) => {
+    const response = await (options?.retry ?? retry)(() => {
+      onAttempt?.()
+      return client.session.messages({ sessionID, limit, before })
+    })
    const items = (response.data ?? []).filter((item) => !!item?.info?.id)
    return {
      session: items.map((item) => cleanMessage(item.info)).sort((a, b) => cmp(a.id, b.id)),
@@ -261,30 +459,153 @@ export function createServerSession(client: OpencodeClient) {
    }
  }

+  const replaceMessages = (sessionID: string, messages: Message[]) => {
+    const messageIDs = new Set(messages.map((message) => message.id))
+    const dropped = (data.message[sessionID] ?? []).filter((message) => !messageIDs.has(message.id))
+    setData("message", sessionID, reconcile(messages, { key: "id" }))
+    setData(
+      produce((draft) => {
+        for (const message of dropped) deleteMessageParts(draft, message.id)
+      }),
+    )
+    return messageIDs
+  }
+
+  const replaceParts = (
+    sessionID: string,
+    items: MessagePage["part"],
+    messageIDs: Set<string>,
+    load?: MessageLoadState,
+  ) => {
+    for (const item of items) {
+      if (!messageIDs.has(item.id)) continue
+      const fetched = load?.clearedMessageParts.has(item.id)
+        ? []
+        : item.part.filter((part) => !SKIP_PARTS.has(part.type))
+      const fetchedIDs = new Set(fetched.map((part) => part.id))
+      const pending = pendingParts.get(sessionID)?.get(item.id)
+      const touched = new Set([...(load?.touchedParts.get(item.id) ?? []), ...(pending ?? [])])
+      for (const part of fetched) {
+        const accumulated = data.part_text_accum_delta[part.id]
+        const base = deltaBases.get(part.id)?.base
+        const preserveDelta =
+          base !== undefined &&
+          accumulated !== undefined &&
+          "text" in part &&
+          typeof part.text === "string" &&
+          part.text.startsWith(base) &&
+          accumulated.startsWith(part.text) &&
+          accumulated !== part.text
+        if (preserveDelta) touched.add(part.id)
+        if (load?.carriedDeltaParts.get(item.id)?.has(part.id) && !preserveDelta) touched.delete(part.id)
+      }
+      for (const partID of load?.carriedDeltaParts.get(item.id) ?? []) {
+        if (!fetchedIDs.has(partID)) touched.delete(partID)
+      }
+      const parts = reconcileFetched(fetched, data.part[item.id] ?? [], { touched })
+      if (!parts.length) {
+        orphanParts.get(sessionID)?.delete(item.id)
+        setData(produce((draft) => deleteMessageParts(draft, item.id)))
+        continue
+      }
+      const partIDs = new Set(parts.map((part) => part.id))
+      setData(
+        "part_text_accum_delta",
+        produce((draft) => {
+          for (const part of data.part[item.id] ?? []) {
+            if (!partIDs.has(part.id) || !touched.has(part.id)) {
+              delete draft[part.id]
+              deltaBases.delete(part.id)
+            }
+          }
+        }),
+      )
+      setData("part", item.id, reconcile(parts, { key: "id" }))
+      orphanParts.get(sessionID)?.delete(item.id)
+    }
+  }
+
+  const applyMessagePage = (
+    sessionID: string,
+    page: MessagePage,
+    load: MessageLoadState | undefined,
+    preserveUnfetched: boolean | ((message: Message) => boolean),
+    cleanupOrphans: boolean,
+  ) => {
+    const merged = mergeOptimisticPage(page, [...(optimistic.get(sessionID)?.values() ?? [])])
+    merged.observed.forEach((item) => {
+      if (!load?.clearedMessageParts.has(item.messageID)) confirmOptimistic(sessionID, item.messageID, item.parts)
+    })
+    const touchedMessages = new Set([...(load?.touchedMessages ?? []), ...(removedMessages.get(sessionID) ?? [])])
+    const messages = reconcileFetched(merged.session, data.message[sessionID] ?? [], {
+      touched: touchedMessages,
+      retained: load?.retainedMessages,
+      preserveUnfetched,
+    })
+    batch(() => {
+      const messageIDs = replaceMessages(sessionID, messages)
+      replaceParts(sessionID, merged.part, messageIDs, load)
+      const orphans = orphanParts.get(sessionID)
+      if (cleanupOrphans && page.complete && orphans) {
+        for (const messageID of orphans) {
+          if (!messageIDs.has(messageID)) setData(produce((draft) => deleteMessageParts(draft, messageID)))
+        }
+        orphanParts.delete(sessionID)
+      }
+      setMeta("limit", sessionID, messages.length)
+      setMeta("cursor", sessionID, merged.cursor)
+      setMeta("complete", sessionID, merged.complete)
+      setMeta("at", sessionID, Date.now())
+    })
+  }
+
  const loadMessages = async (sessionID: string, limit: number, before?: string, mode?: "replace" | "prepend") => {
    if (meta.loading[sessionID]) return
-    const generation = generations.get(sessionID) ?? 0
+    const active = generation(sessionID)
+    const load: MessageLoadState = {
+      touchedMessages: new Set(),
+      removedMessages: new Set(),
+      retainedMessages: new Set(),
+      touchedParts: new Map(),
+      deltaParts: new Map(),
+      carriedDeltaParts: new Map(),
+      removedParts: new Map(),
+      optimisticParts: new Map(),
+      orphanParents: new Set(),
+      clearedMessageParts: new Set(),
+    }
+    messageLoads.set(sessionID, load)
    setMeta("loading", sessionID, true)
-    await fetchMessages(sessionID, limit, before)
+    let applied = false
+    await fetchMessages(sessionID, limit, before, () => resetMessageLoad(sessionID, load))
      .then((page) => {
-        if ((generations.get(sessionID) ?? 0) !== generation) return
-        const next = mergeOptimisticPage(page, [...(optimistic.get(sessionID)?.values() ?? [])])
-        next.confirmed.forEach((messageID) => clearOptimistic(sessionID, messageID))
-        const messages = mode === "prepend" ? merge(data.message[sessionID] ?? [], next.session) : next.session
-        batch(() => {
-          setData("message", sessionID, reconcile(messages, { key: "id" }))
-          for (const item of next.part) {
-            const parts = item.part.filter((part) => !SKIP_PARTS.has(part.type))
-            if (parts.length) setData("part", item.id, reconcile(parts, { key: "id" }))
-          }
-          setMeta("limit", sessionID, messages.length)
-          setMeta("cursor", sessionID, next.cursor)
-          setMeta("complete", sessionID, next.complete)
-          setMeta("at", sessionID, Date.now())
-        })
+        if (generations.get(sessionID) !== active) return
+        const first = page.session.reduce<Message | undefined>(
+          (oldest, message) => (!oldest || cmpMessage(message, oldest) < 0 ? message : oldest),
+          undefined,
+        )
+        const preserveUnfetched =
+          mode === "prepend" || (!page.complete && (!first || ((message: Message) => cmpMessage(message, first) < 0)))
+        applyMessagePage(
+          sessionID,
+          page,
+          messageLoads.get(sessionID) === load ? load : undefined,
+          preserveUnfetched,
+          mode !== "prepend",
+        )
+        applied = true
      })
      .finally(() => {
-        if ((generations.get(sessionID) ?? 0) === generation) setMeta("loading", sessionID, false)
+        if (!applied && generations.get(sessionID) === active && messageLoads.get(sessionID) === load) {
+          for (const messageID of load.orphanParents) {
+            if (!orphanParts.get(sessionID)?.has(messageID)) continue
+            setData(produce((draft) => deleteMessageParts(draft, messageID)))
+            orphanParts.get(sessionID)?.delete(messageID)
+          }
+          if (orphanParts.get(sessionID)?.size === 0) orphanParts.delete(sessionID)
+        }
+        if (messageLoads.get(sessionID) === load) messageLoads.delete(sessionID)
+        if (generations.get(sessionID) === active) setMeta("loading", sessionID, false)
      })
  }

@@ -339,7 +660,13 @@ export function createServerSession(client: OpencodeClient) {
    const eventID = eventSessionID(event)
    if (eventID) {
      touch(eventID)
-      if (!data.info[eventID]) void resolve(eventID).catch(() => {})
+      if (
+        !data.info[eventID] &&
+        event.type !== "session.created" &&
+        event.type !== "session.updated" &&
+        event.type !== "session.deleted"
+      )
+        void resolve(eventID).catch(() => {})
    }
    switch (event.type) {
      case "session.created":
@@ -378,6 +705,21 @@ export function createServerSession(client: OpencodeClient) {
      }
      case "message.updated": {
        const info = cleanMessage((event.properties as { info: Message }).info)
+        const load = messageLoads.get(info.sessionID)
+        load?.touchedMessages.add(info.id)
+        load?.removedMessages.delete(info.id)
+        const items = optimistic.get(info.sessionID)
+        const item = items?.get(info.id)
+        if (items && item) {
+          if (item.parts.length === 0) clearOptimistic(info.sessionID, info.id)
+          if (item.parts.length > 0) items.set(info.id, { ...item, confirmedMessage: true })
+        }
+        const orphans = orphanParts.get(info.sessionID)
+        orphans?.delete(info.id)
+        if (orphans?.size === 0) orphanParts.delete(info.sessionID)
+        const removedMessagesForSession = removedMessages.get(info.sessionID)
+        removedMessagesForSession?.delete(info.id)
+        if (removedMessagesForSession?.size === 0) removedMessages.delete(info.sessionID)
        const messages = data.message[info.sessionID]
        if (!messages) {
          setData("message", info.sessionID, [info])
@@ -395,6 +737,20 @@ export function createServerSession(client: OpencodeClient) {
      }
      case "message.removed": {
        const props = event.properties as { sessionID: string; messageID: string }
+        const load = messageLoads.get(props.sessionID)
+        load?.touchedMessages.add(props.messageID)
+        load?.removedMessages.add(props.messageID)
+        load?.clearedMessageParts.add(props.messageID)
+        load?.deltaParts.delete(props.messageID)
+        load?.carriedDeltaParts.delete(props.messageID)
+        load?.removedParts.delete(props.messageID)
+        load?.optimisticParts.delete(props.messageID)
+        pendingParts.get(props.sessionID)?.delete(props.messageID)
+        if (pendingParts.get(props.sessionID)?.size === 0) pendingParts.delete(props.sessionID)
+        const removedMessagesForSession = removedMessages.get(props.sessionID) ?? new Set<string>()
+        removedMessagesForSession.add(props.messageID)
+        removedMessages.set(props.sessionID, removedMessagesForSession)
+        clearOptimistic(props.sessionID, props.messageID)
        setData(
          produce((draft) => {
            const messages = draft.message[props.sessionID]
@@ -402,8 +758,7 @@ export function createServerSession(client: OpencodeClient) {
              const result = Binary.search(messages, props.messageID, (message) => message.id)
              if (result.found) messages.splice(result.index, 1)
            }
-            for (const part of draft.part[props.messageID] ?? []) delete draft.part_text_accum_delta[part.id]
-            delete draft.part[props.messageID]
+            deleteMessageParts(draft, props.messageID)
          }),
        )
        return
@@ -411,6 +766,42 @@ export function createServerSession(client: OpencodeClient) {
      case "message.part.updated": {
        const part = (event.properties as { part: Part }).part
        if (SKIP_PARTS.has(part.type)) return
+        const messages = data.message[part.sessionID]
+        const load = messageLoads.get(part.sessionID)
+        const missing = !messages || !Binary.search(messages, part.messageID, (message) => message.id).found
+        // Outside a page load, accepting a part without its ordered parent event would create an unbounded orphan.
+        if (
+          missing &&
+          (!load ||
+            load.clearedMessageParts.has(part.messageID) ||
+            removedMessages.get(part.sessionID)?.has(part.messageID))
+        )
+          return
+        if (missing) {
+          const orphans = orphanParts.get(part.sessionID) ?? new Set<string>()
+          orphans.add(part.messageID)
+          orphanParts.set(part.sessionID, orphans)
+          load?.orphanParents.add(part.messageID)
+        }
+        const deltas = load?.deltaParts.get(part.messageID)
+        deltas?.delete(part.id)
+        if (deltas?.size === 0) load?.deltaParts.delete(part.messageID)
+        const carried = load?.carriedDeltaParts.get(part.messageID)
+        carried?.delete(part.id)
+        if (carried?.size === 0) load?.carriedDeltaParts.delete(part.messageID)
+        const removed = load?.removedParts.get(part.messageID)
+        removed?.delete(part.id)
+        if (removed?.size === 0) load?.removedParts.delete(part.messageID)
+        const pending = pendingParts.get(part.sessionID)?.get(part.messageID)
+        pending?.delete(part.id)
+        if (pending?.size === 0) pendingParts.get(part.sessionID)?.delete(part.messageID)
+        if (pendingParts.get(part.sessionID)?.size === 0) pendingParts.delete(part.sessionID)
+        const optimistic = load?.optimisticParts.get(part.messageID)
+        optimistic?.delete(part.id)
+        if (optimistic?.size === 0) load?.optimisticParts.delete(part.messageID)
+        deltaBases.delete(part.id)
+        trackPartChange(part.sessionID, part.messageID, part.id)
+        confirmOptimisticPart(part.sessionID, part.messageID, part)
        setData(
          "part_text_accum_delta",
          produce((draft) => void delete draft[part.id]),
@@ -431,10 +822,34 @@ export function createServerSession(client: OpencodeClient) {
        return
      }
      case "message.part.removed": {
-        const props = event.properties as { messageID: string; partID: string }
+        const props = event.properties as { sessionID: string; messageID: string; partID: string }
+        // Part removal is event-only on the server, so its tombstone lasts until a later update or eviction.
+        const pending = pendingParts.get(props.sessionID) ?? new Map<string, Set<string>>()
+        const parts = pending.get(props.messageID) ?? new Set<string>()
+        parts.add(props.partID)
+        pending.set(props.messageID, parts)
+        pendingParts.set(props.sessionID, pending)
+        const deltas = messageLoads.get(props.sessionID)?.deltaParts.get(props.messageID)
+        deltas?.delete(props.partID)
+        if (deltas?.size === 0) messageLoads.get(props.sessionID)?.deltaParts.delete(props.messageID)
+        const load = messageLoads.get(props.sessionID)
+        const carried = load?.carriedDeltaParts.get(props.messageID)
+        carried?.delete(props.partID)
+        if (carried?.size === 0) load?.carriedDeltaParts.delete(props.messageID)
+        if (load) {
+          const parts = load.removedParts.get(props.messageID) ?? new Set<string>()
+          parts.add(props.partID)
+          load.removedParts.set(props.messageID, parts)
+          const optimistic = load.optimisticParts.get(props.messageID)
+          optimistic?.delete(props.partID)
+          if (optimistic?.size === 0) load.optimisticParts.delete(props.messageID)
+        }
+        trackPartChange(props.sessionID, props.messageID, props.partID)
+        clearOptimisticPart(props.sessionID, props.messageID, props.partID)
        setData(
          produce((draft) => {
            delete draft.part_text_accum_delta[props.partID]
+            deltaBases.delete(props.partID)
            const parts = draft.part[props.messageID]
            if (!parts) return
            const result = Binary.search(parts, props.partID, (part) => part.id)
@@ -445,13 +860,31 @@ export function createServerSession(client: OpencodeClient) {
        return
      }
      case "message.part.delta": {
-        const props = event.properties as { messageID: string; partID: string; field: string; delta: string }
+        const props = event.properties as {
+          sessionID: string
+          messageID: string
+          partID: string
+          field: string
+          delta: string
+        }
        const parts = data.part[props.messageID]
        if (!parts) return
        const result = Binary.search(parts, props.partID, (part) => part.id)
        if (!result.found) return
+        trackPartChange(props.sessionID, props.messageID, props.partID)
+        const load = messageLoads.get(props.sessionID)
+        if (load) {
+          const parts = load.deltaParts.get(props.messageID) ?? new Set<string>()
+          parts.add(props.partID)
+          load.deltaParts.set(props.messageID, parts)
+          const carried = load.carriedDeltaParts.get(props.messageID)
+          carried?.delete(props.partID)
+          if (carried?.size === 0) load.carriedDeltaParts.delete(props.messageID)
+        }
        const field = props.field as keyof (typeof parts)[number]
        const current = parts[result.index]?.[field]
+        if (!deltaBases.has(props.partID) && typeof current === "string")
+          deltaBases.set(props.partID, { base: current, sessionID: props.sessionID })
        setData(
          "part_text_accum_delta",
          props.partID,
@@ -559,32 +992,70 @@ export function createServerSession(client: OpencodeClient) {
    },
    optimistic: {
      add(input: { sessionID: string; message: Message; parts: Part[] }) {
+        const parts = input.parts
+          .filter((part) => !!part?.id && !SKIP_PARTS.has(part.type))
+          .sort((a, b) => cmp(a.id, b.id))
+        const load = messageLoads.get(input.sessionID)
+        if (load?.clearedMessageParts.has(input.message.id)) {
+          const touched = load.touchedParts.get(input.message.id) ?? new Set<string>()
+          parts.forEach((part) => touched.add(part.id))
+          load.touchedParts.set(input.message.id, touched)
+        }
+        if (load) {
+          load.removedMessages.delete(input.message.id)
+          load.optimisticParts.set(input.message.id, new Set(parts.map((part) => part.id)))
+        }
        const items = optimistic.get(input.sessionID)
-        if (items) items.set(input.message.id, input)
-        if (!items) optimistic.set(input.sessionID, new Map([[input.message.id, input]]))
+        const removedMessagesForSession = removedMessages.get(input.sessionID)
+        removedMessagesForSession?.delete(input.message.id)
+        if (removedMessagesForSession?.size === 0) removedMessages.delete(input.sessionID)
+        if (items) items.set(input.message.id, { ...input, parts, confirmedParts: [] })
+        if (!items)
+          optimistic.set(input.sessionID, new Map([[input.message.id, { ...input, parts, confirmedParts: [] }]]))
        setData("message", input.sessionID, (messages = []) => merge(messages, [input.message]))
        setData(
-          "part",
-          input.message.id,
-          input.parts.filter((part) => !!part?.id).sort((a, b) => cmp(a.id, b.id)),
+          "part_text_accum_delta",
+          produce((draft) => {
+            for (const part of [...(data.part[input.message.id] ?? []), ...parts]) {
+              delete draft[part.id]
+              deltaBases.delete(part.id)
+            }
+          }),
        )
+        setData("part", input.message.id, parts)
      },
      remove(input: { sessionID: string; messageID: string }) {
+        const item = optimistic.get(input.sessionID)?.get(input.messageID)
+        if (!item) return
+        messageLoads.get(input.sessionID)?.optimisticParts.delete(input.messageID)
        clearOptimistic(input.sessionID, input.messageID)
+        if (item.confirmedMessage) {
+          const partIDs = new Set(item.parts.map((part) => part.id))
+          setData(
+            produce((draft) => {
+              for (const part of item.parts) {
+                delete draft.part_text_accum_delta[part.id]
+                deltaBases.delete(part.id)
+              }
+              const parts = draft.part[input.messageID]
+              if (!parts) return
+              draft.part[input.messageID] = parts.filter((part) => !partIDs.has(part.id))
+              if (draft.part[input.messageID]?.length === 0) delete draft.part[input.messageID]
+            }),
+          )
+          return
+        }
        setData("message", input.sessionID, (messages) => messages?.filter((message) => message.id !== input.messageID))
-        setData(
-          "part",
-          produce((draft) => void delete draft[input.messageID]),
-        )
+        setData(produce((draft) => deleteMessageParts(draft, input.messageID)))
      },
    },
    diff(sessionID: string, options?: { force?: boolean }) {
      touch(sessionID)
      if (data.session_diff[sessionID] !== undefined && !options?.force) return Promise.resolve()
      return runInflight(inflightDiff, sessionID, () => {
-        const generation = generations.get(sessionID) ?? 0
+        const active = generation(sessionID)
        return retry(() => client.session.diff({ sessionID })).then((result) => {
-          if ((generations.get(sessionID) ?? 0) !== generation) return
+          if (generations.get(sessionID) !== active) return
          setData("session_diff", sessionID, reconcile(cleanDiffs(result.data), { key: "file" }))
        })
      })
@@ -593,9 +1064,9 @@ export function createServerSession(client: OpencodeClient) {
      touch(sessionID)
      if (data.todo[sessionID] !== undefined && !options?.force) return Promise.resolve()
      return runInflight(inflightTodo, sessionID, () => {
-        const generation = generations.get(sessionID) ?? 0
+        const active = generation(sessionID)
        return retry(() => client.session.todo({ sessionID })).then((result) => {
-          if ((generations.get(sessionID) ?? 0) !== generation) return
+          if (generations.get(sessionID) !== active) return
          setData("todo", sessionID, reconcile(result.data ?? [], { key: "id" }))
        })
      })
@@ -1,4 +1,11 @@
-import type { Config, OpencodeClient, Path, Project, ProviderAuthResponse } from "@opencode-ai/sdk/v2/client"
+import type {
+  Config,
+  McpResource,
+  OpencodeClient,
+  Path,
+  Project,
+  ProviderAuthResponse,
+} from "@opencode-ai/sdk/v2/client"
 import { showToast } from "@/utils/toast"
 import { getFilename } from "@opencode-ai/core/util/path"
 import { type Accessor, batch, createMemo, getOwner, onCleanup, onMount, untrack } from "solid-js"
@@ -15,6 +22,7 @@ import {
  loadPathQuery,
  loadProjectsQuery,
  loadProvidersQuery,
+  loadReferencesQuery,
 } from "./global-sync/bootstrap"
 import { createChildStoreManager } from "./global-sync/child-store"
 import { applyDirectoryEvent, applyGlobalEvent } from "./global-sync/event-reducer"
@@ -56,6 +64,13 @@ export const loadMcpQuery = (scope: ServerScope, directory: string, sdk: Opencod
    queryFn: () => sdk.mcp.status().then((r) => r.data ?? {}),
  })

+export const loadMcpResourcesQuery = (scope: ServerScope, directory: string, sdk: OpencodeClient) =>
+  queryOptions<Record<string, McpResource>>({
+    queryKey: [scope, directory, "mcpResources"] as const,
+    queryFn: () => sdk.experimental.resource.list().then((r) => r.data ?? {}),
+    placeholderData: {},
+  })
+
 export const loadLspQuery = (scope: ServerScope, directory: string, sdk: OpencodeClient) =>
  queryOptions({
    queryKey: [scope, directory, "lsp"] as const,
@@ -75,7 +90,9 @@ function makeQueryOptionsApi(
    path: (directory: PathKey | null) =>
      loadPathQuery(scope, directory, directory === null ? serverSDK() : sdkFor(directory)),
    agents: (directory: PathKey) => loadAgentsQuery(scope, directory, sdkFor(directory)),
+    references: (directory: PathKey) => loadReferencesQuery(scope, directory, sdkFor(directory)),
    mcp: (directory: PathKey) => loadMcpQuery(scope, directory, sdkFor(directory)),
+    mcpResources: (directory: PathKey) => loadMcpResourcesQuery(scope, directory, sdkFor(directory)),
    lsp: (directory: PathKey) => loadLspQuery(scope, directory, sdkFor(directory)),
    sessions: (directory: PathKey) => ({ queryKey: [scope, directory, "loadSessions"] as const }),
  }
@@ -396,6 +413,9 @@ export function createServerSyncContextInner(serverSDK: ServerSDK) {
      loadLsp: () => {
        void queryClient.fetchQuery(queryOptionsApi.lsp(key))
      },
+      loadReferences: () => {
+        void queryClient.fetchQuery(queryOptionsApi.references(key))
+      },
    })
  })

@@ -484,6 +504,7 @@ export function createServerSyncContextInner(serverSDK: ServerSDK) {
          },
          refresh: async () => {
            await queryClient.refetchQueries(queryOptionsApi.mcp(key))
+            await queryClient.refetchQueries(queryOptionsApi.mcpResources(key))
          },
        })
      },
@@ -277,7 +277,7 @@ export const { use: useServer, provider: ServerProvider } = createSimpleContext(
      })
    }

-    const isReady = createMemo(() => ready() && !!state.active)
+    const isReady = Object.assign(createMemo(() => ready() && !!state.active), { promise: ready.promise })

    const scope = (key = state.active) => ServerScope.fromServerKey(key, props.canonicalLocalServer)
    const projects = createServerProjects({ scope, store, setStore })
@@ -51,7 +51,7 @@ export const { use: useTabs, provider: TabsProvider } = createSimpleContext({
    const fallback = server.key
    const [store, setStore, _, ready] = persisted(
      {
-        ...Persist.global("tabs"),
+        ...Persist.window("tabs"),
        migrate: (value: unknown) => {
          if (!Array.isArray(value)) return value
          return value.map((tab) => {
@@ -62,7 +62,7 @@ export const { use: useTabs, provider: TabsProvider } = createSimpleContext({
      },
      createStore<Tab[]>([]),
    )
-    const [recent, setRecent, , recentReady] = persisted(Persist.global("tabs.recent"), createStore<RecentTab>({}))
+    const [recent, setRecent, , recentReady] = persisted(Persist.window("tabs.recent"), createStore<RecentTab>({}))

    const params = useParams()
    const navigate = useNavigate()
@@ -138,12 +138,14 @@ export const { use: useTabs, provider: TabsProvider } = createSimpleContext({
        const next = { type: "session" as const, ...tab }
        const existing = store.find((item) => tabKey(item) === tabKey(next))
        if (existing) return existing
-        setStore(
-          produce((tabs) => {
-            if (tabs.some((item) => tabKey(item) === tabKey(next))) return
-            tabs.push(next)
-          }),
-        )
+        void startTransition(() => {
+          setStore(
+            produce((tabs) => {
+              if (tabs.some((item) => tabKey(item) === tabKey(next))) return
+              tabs.push(next)
+            }),
+          )
+        })
        return next
      },
      reorder(keys: string[]) {
@@ -163,27 +165,29 @@ export const { use: useTabs, provider: TabsProvider } = createSimpleContext({
      },
      newDraft(draft: Omit<DraftTab, "type" | "draftID">, prompt?: string) {
        const draftID = uuid()
-        setStore(
-          produce((tabs) => {
-            tabs.push({ type: "draft", draftID, ...draft })
-          }),
-        )
-        navigate(prompt ? `${draftHref(draftID)}&prompt=${encodeURIComponent(prompt)}` : draftHref(draftID))
+        void startTransition(() => {
+          setStore(
+            produce((tabs) => {
+              tabs.push({ type: "draft", draftID, ...draft })
+            }),
+          )
+          navigate(prompt ? `${draftHref(draftID)}&prompt=${encodeURIComponent(prompt)}` : draftHref(draftID))
+        })
      },
      updateDraft(draftID: string, draft: Partial<Omit<DraftTab, "type" | "draftID">>) {
-        setStore(
-          (tab) => tab.type === "draft" && tab.draftID === draftID,
-          produce((tab) => Object.assign(tab, draft)),
-        )
+        void startTransition(() => {
+          setStore(
+            (tab) => tab.type === "draft" && tab.draftID === draftID,
+            produce((tab) => Object.assign(tab, draft)),
+          )
+        })
      },
      promoteDraft(draftID: string, session: Omit<SessionTab, "type">) {
-        // We're viewing this draft when /new-session?draftId=… points at it. Promoting
-        // replaces the draft tab with a session tab, so the draft route would stop resolving
-        // and fall back home. Navigate to the new session first so we leave /new-session
-        // before the draft is removed from the store.
+        // Keep the replacement and navigation atomic so /new-session never renders
+        // after its backing draft tab has been removed from the store.
        const active = location.pathname === "/new-session" && location.query.draftId === draftID
        const next = { type: "session" as const, ...session }
-        startTransition(() => {
+        void startTransition(() => {
          setStore(
            produce((tabs) => {
              const index = tabs.findIndex((tab) => tab.type === "draft" && tab.draftID === draftID)
@@ -0,0 +1,13 @@
+import { describe, expect, test } from "bun:test"
+import { DESKTOP_MENU } from "./desktop-menu"
+
+describe("desktop menu", () => {
+  test("exports logs through the desktop command registry", () => {
+    const items = DESKTOP_MENU.flatMap((menu) => menu.items ?? []).filter(
+      (item) => item.type === "item" && item.label === "Export Logs...",
+    )
+
+    expect(items).toHaveLength(2)
+    expect(items.every((item) => item.type === "item" && item.command === "logs.export" && !item.action)).toBe(true)
+  })
+})
@@ -388,6 +388,20 @@ export const dict = {
  "wsl.onboarding.chooseDistroFirst": "Choose a distro first.",
  "wsl.onboarding.loadFailed": "Failed to load WSL state.",
  "wsl.onboarding.loading": "Loading...",
+  "wsl.onboarding.installedDistros": "Installed distros",
+  "wsl.onboarding.checkAgain": "Check again",
+  "wsl.onboarding.distroStatus.ready": "Ready",
+  "wsl.onboarding.distroStatus.checking": "Checking...",
+  "wsl.onboarding.distroStatus.opencodeMissing": "OpenCode not installed",
+  "wsl.onboarding.distroStatus.missingTools": "Missing bash, curl",
+  "wsl.onboarding.distroStatus.unsupported": "Unsupported · Use WSL 2",
+  "wsl.onboarding.needAnotherDistro": "Need another distro?",
+  "wsl.onboarding.needAnotherDistroHint": "Install a Linux distribution from the WSL catalog",
+  "wsl.onboarding.wslNotInstalled.title": "WSL not installed",
+  "wsl.onboarding.wslNotInstalled.description":
+    "WSL (Windows Subsystem for Linux) is required before OpenCode can add a WSL server",
+  "wsl.onboarding.wslUnavailable.title": "WSL unavailable",
+  "wsl.onboarding.wslUnavailable.description": "OpenCode could not verify WSL on this machine.",
  "wsl.onboarding.installWsl": "Install WSL",
  "wsl.onboarding.windowsRestartRequired": "Restart Windows to finish installing WSL, then reopen OpenCode.",
  "wsl.onboarding.next": "Next",
@@ -397,6 +411,7 @@ export const dict = {
  "wsl.onboarding.install": "Install",
  "wsl.onboarding.installing": "Installing...",
  "wsl.onboarding.installDistro": "Install distro",
+  "wsl.onboarding.searchDistros": "Search distros",
  "wsl.onboarding.wsl2Required": "WSL 2 is required.",
  "wsl.onboarding.toolsRequired": "This distro needs bash and curl.",
  "wsl.onboarding.openTerminal": "Open terminal",
@@ -604,7 +619,12 @@ export const dict = {
  "session.tab.session": "Session",
  "session.tab.review": "Review",
  "session.tab.context": "Context",
+  "session.tab.unknown": "Unknown Session",
  "session.panel.reviewAndFiles": "Review and files",
+  "session.error.notFound": "This session cannot be found",
+  "session.error.notFound.description": "This tab points to a session that no longer exists on this server.",
+  "session.error.notFound.closeTab": "Close Tab",
+  "session.error.serverConnection": "Can't connect to this server",
  "session.review.filesChanged": "{{count}} Files Changed",
  "session.review.change.one": "Change",
  "session.review.change.other": "Changes",
@@ -637,6 +657,10 @@ export const dict = {
  "session.todo.expand": "Expand",
  "session.todo.progress": "{{done}} of {{total}} todos completed",
  "session.question.progress": "{{current}} of {{total}} questions",
+  "session.question.minimize": "Minimize question",
+  "session.question.restore": "Restore question",
+  "session.question.pending.one": "{{count}} pending question",
+  "session.question.pending.other": "{{count}} pending questions",
  "session.followupDock.summary.one": "{{count}} queued message",
  "session.followupDock.summary.other": "{{count}} queued messages",
  "session.followupDock.sendNow": "Send now",
--- a/Show More
+++ b/Show More