Merge remote-tracking branch 'origin/dev' into httpapi-codegen

# ------------------------ >8 ------------------------
# Do not modify or remove the line above.
# Everything below it will be ignored.
#
# Conflicts:
#	packages/server/src/groups/session.ts

.github/workflows/test.yml

@@ -69,6 +69,11 @@ jobs:
         env:
           OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER: ${{ runner.os == 'Windows' && 'true' || 'false' }}
 
+      - name: Check generated client
+        if: runner.os == 'Linux'
+        working-directory: packages/client
+        run: bun run check:generated
+
       - name: Run HttpApi exerciser gates
         if: runner.os == 'Linux'
         working-directory: packages/opencode

CONTEXT.md

@@ -67,6 +67,21 @@ Provider-neutral sampling and output controls, partitioned from provider semanti
 **PTY Environment**:
 The host-supplied environment overlay applied by the server when creating a PTY, observed for the request Location and resolved PTY working directory.
 
+**OpenCode Client**:
+The generated Effect API shared by networked and in-process consumers, executed through an `HttpClient` against the same `HttpApi` router and handlers.
+_Avoid_: Remote client
+
+**SDK Contract IR**:
+The runtime-neutral compiled representation of the authoritative `HttpApi`, preserving encoded and decoded type projections plus transport metadata so independent SDK emitters can choose their public value model and runtime interpreter.
+
+**Embedded OpenCode**:
+A scoped in-process host that structurally extends the **OpenCode Client**, supplies an in-memory HTTP transport, and exposes additional same-process capabilities directly.
+_Avoid_: Local implementation
+
+**Page**:
+A bounded ordered result containing `items` and opaque `previous` and `next` cursor links for navigating the same query in either direction.
+_Avoid_: Response envelope
+
 ## Relationships
 
 - A **System Context** is an opaque carrier composed from zero or more **Context Sources**.
@@ -117,6 +132,51 @@ The host-supplied environment overlay applied by the server when creating a PTY,
 - **Model Request Options** remain provider-semantic through Catalog resolution. The Session runner maps them into the LLM package's provider-option namespace; the selected protocol adapter alone owns provider wire encoding.
 - **Generation Controls**, protocol-semantic **Model Request Options**, and compatibility request body fields are separate Catalog domains. A shared ingestion adapter partitions legacy and models.dev AI-SDK-shaped options before routing.
 - The **PTY Environment** is a server concern rather than a Core PTY concern. PTY creation merges caller values, then the host overlay, then Core-forced terminal invariants such as `TERM` and `OPENCODE_TERMINAL`.
+- Networked and **Embedded OpenCode** use the same **OpenCode Client** and preserve the full HTTP encoding, routing, middleware, and decoding boundary; only the `HttpClient` transport differs.
+- The Effect-native network constructor obtains `HttpClient.HttpClient` from its environment so callers own transport selection, recording, tracing, retries, and tests. Convenience runtimes may provide a fetch transport separately.
+- Creating **Embedded OpenCode** is scoped. Closing its owning Scope releases the in-process server resources, database resources, registrations, and fibers.
+- **Embedded OpenCode** exposes shared client capabilities and embedded-only capabilities on one object; consumers do not navigate through a nested `.client` property.
+- The beta **OpenCode Client** currently uses plural consumer-facing capability groups such as `sessions`; whether the stable Session namespace should instead be singular `session` must be settled before stabilization. Internal server identifiers do not implicitly define public client names.
+- The public `HttpApi` is authoritative for shared **OpenCode Client** capabilities: the server and code generation consume the same hosted `SessionGroup`. Codegen may assign a separate consumer-facing group name without reconstructing group membership or endpoint contracts.
+- SDK generation reflects the public `HttpApi` once into an **SDK Contract IR**. Promise and Effect emitters share endpoint structure and transport metadata without being required to expose identical public values: an emitter may select encoded wire types, decoded domain types, compile-time brands, runtime validation, and its own execution abstraction independently.
+- The first Effect emitter is the rich projection: it exposes decoded Effect-native values, preserves brands and schema transformations, performs runtime schema decoding, and delegates transport interpretation to `HttpApiClient`. Lighter wire-shaped Effect output remains possible through another emitter policy rather than constraining the shared IR.
+- The rich Effect emitter regenerates private executable schemas when the **SDK Contract IR** proves that their transport semantics can be reproduced exactly. Contracts with authoritative custom transformations use the import-based Effect emitter against the canonical Protocol `HttpApi`; the Promise emitter still derives zero-Effect structural wire types from the same IR.
+- `@opencode-ai/protocol` owns the authoritative Session `HttpApi`. The server and client generator consume the exact hosted `SessionGroup`, including `compact`, `wait`, and `context`.
+- The first Promise emitter targets the same clean domain-oriented method organization rather than Hey API source compatibility. It returns unwrapped values directly, rejects declared and infrastructure failures, and begins with minimal client-level transport configuration; result wrappers, interceptors, and legacy generated signatures are outside the initial surface.
+- The first Promise emitter parses response syntax and trusts its generated structural types; it does not perform runtime structural validation. Malformed payload syntax fails, while a syntactically valid shape mismatch is not detected at the SDK boundary. Standalone validator generation remains an optional future emitter policy.
+- Declared Promise-client failures retain their tagged structural wire values and have generated type guards. Consumers do not depend on generated `Error` subclass identity, preserving discrimination across package copies and realms while remaining structurally aligned with Effect domain errors.
+- Promise-client infrastructure failures use one generated `ClientError` class with a structured reason such as transport failure, unexpected status, unsupported content type, or malformed response. Promise methods reject with either a tagged declared domain failure or `ClientError`, matching the Effect client's conceptual domain/infrastructure error division.
+- Promise methods accept a separate optional per-call transport-options argument containing `AbortSignal` and header overrides. Cancellation and transport metadata do not enter the domain input object; broader interceptor and response-mode APIs remain deferred.
+- Promise streaming methods return a lazy `AsyncIterable` directly rather than a Promise-wrapped stream object. Iteration opens the connection, `AbortSignal` cancels it, and ending iteration closes the underlying request; the Effect emitter analogously returns `Stream` directly.
+- Promise SSE connection establishment, declared HTTP failures, and infrastructure failures occur during `AsyncIterable` iteration, beginning with its first `next()` call, rather than during synchronous method construction.
+- Neither generated streaming runtime automatically reconnects after disconnection. Promise `AsyncIterable` and Effect `Stream` fail explicitly; live consumers refresh and resubscribe, while durable sequence-based resume remains explicit composition above the generated client.
+- Promise client construction is synchronous and network-free. It requires `baseUrl`, defaults to `globalThis.fetch`, accepts client-level headers, and merges them with per-call header overrides.
+- Effect client construction accepts an explicit `baseUrl` and obtains `HttpClient.HttpClient` from the Effect environment. It does not install fetch or duplicate per-call transport policy; callers transform/provide the client for headers, tracing, retries, recording, and tests, while fiber interruption owns cancellation.
+- Promise and Effect emitters each own their generated public type modules. The **SDK Contract IR**, not a physically shared generated type package, is the common source; this permits zero-Effect wire types and rich decoded Effect types to evolve independently.
+- Promise and Effect network clients ship from `@opencode-ai/client` behind isolated root and `/effect` exports. The root has no runtime path to Effect; `/effect` imports only Effect, Schema, and Protocol.
+- The Effect-native scoped host belongs to `@opencode-ai/sdk-next`, which will assume the existing `@opencode-ai/sdk` name after legacy consumers migrate. Client remains network-only and SDK depends one-way on Client.
+- SDK executes Server's assembled `HttpRouter` in memory. It opens no listener and performs no network I/O, while preserving Server routing, middleware, codecs, handlers, and errors.
+- The Effect Client and SDK re-export their decoded datatype facade from Schema so callers do not depend on internal package locations or Core's versioned names.
+- A capability intended for both networked and **Embedded OpenCode** belongs in the authoritative public `HttpApi`; embedded-only same-process capabilities extend **Embedded OpenCode** separately.
+- `sessions.events({ sessionID, after })` is a public durable Session event stream. It verifies the Session, replays durable events after the optional aggregate sequence, continues with newly committed durable events, excludes live-only fragments, and is transported as SSE in both networked and embedded modes.
+- `events.subscribe()` is a distinct public instance-wide live stream for Session and non-Session activity. It has no replay guarantee and includes connection, heartbeat, and instance-disposal lifecycle events; consumers recover from disconnection by refreshing authoritative state.
+- A Session ID is not an optional filter on `events.subscribe()`: instance-wide live events and durable Session events have different schemas, replay guarantees, cursors, lifecycle events, and failure behavior.
+- The initial common OpenCode Client does not expose server-global event aggregation. `events.subscribe()` is bounded to the connected OpenCode instance or workspace; any future cross-instance administrative stream requires a separately designed API.
+- `events.subscribe()` does not automatically reconnect after transport loss. The live-only stream fails with `ClientError`; consumers refresh authoritative state before explicitly opening a new subscription because events missed during disconnection cannot be replayed.
+- `sessions.events({ sessionID, after })` returns the generated HTTP client's cold durable event stream and does not build reconnection policy into the endpoint or client constructor. Transport loss fails the stream with `ClientError`. Callers may compose an explicit resuming stream above it by retaining the last observed durable sequence and opening a new subscription with `after`; any reusable resume helper remains a separate API design question.
+- The stable `sessions.list(...)` design returns a **Page** in both networked and **Embedded OpenCode**; embedded execution does not define a separate unbounded array-returning list operation. The beta client currently preserves the existing HTTP `{ data, cursor }` envelope until emitter-level Page projection is implemented.
+- Session list cursors are opaque branded values carrying continuation query and ordering state. Consumers pass them back unchanged and do not inspect storage anchors or encoded filter fields.
+- A Session list continuation accepts only its opaque cursor. Scope, filters, ordering, and page size are fixed by the initial query and carried by that cursor.
+- `sessions.messages(...)` returns a **Page** and uses the same cursor discipline as `sessions.list(...)`: the initial request supplies `sessionID`, ordering, and page size; continuation supplies `sessionID` plus only an opaque branded message cursor carrying ordering, page size, direction, and message anchor. Using a cursor with another Session is invalid.
+- `sessions.message({ sessionID, messageID })` is a required resource lookup. An unknown Session fails with `SessionNotFoundError`; a known Session with an absent or differently owned message fails with `SessionMessageNotFoundError` without disclosing cross-Session ownership. Absence is not represented as `undefined` across the public HTTP boundary.
+- `sessions.interrupt({ sessionID })` first verifies that the durable Session exists, failing with `SessionNotFoundError` otherwise. For a known Session, interruption is idempotent: idle, already-settled, or locally unowned execution is a no-op.
+- `sessions.context({ sessionID })` preserves the existing message-only operation. It returns projected conversational messages selected as Session context; it does not include or represent the complete provider request context, whose baseline system context and other contributions remain separate.
+- **Open question**: Should a future, separately named operation expose the complete provider request context, including baseline system context, selected source contributions, and context-epoch metadata?
+- `sessions.prompt(...)` exposes `resume?: boolean`. Omitting it preserves durable admission followed by an advisory execution wake; `resume: false` requests durable admit-only behavior.
+- The public operation remains `sessions.prompt(...)`; `SessionInput.admit` is the internal primitive, while the public `Admission` result and `resume` option express its durable admission semantics.
+- `sessions.create(...)` accepts an optional `location`. Omission resolves through the connected OpenCode instance's default or current location; an explicit value selects a known location. Networked and embedded transports use the same handler semantics.
+- `sessions.switchAgent({ sessionID, agent })` is part of the common client alongside `sessions.switchModel(...)`. It affects subsequent Session activity and fails with `SessionNotFoundError` for an unknown Session.
+- The **Embedded OpenCode** Layer delegates to the same scoped creation path; it does not define a second implementation.
 - A **PTY Environment** adapter observes plugins in the request Location while passing the resolved PTY working directory to the hook; standalone servers use an empty adapter.
 - A **Mid-Conversation System Message** lowers to the provider's native chronological instruction role when supported and to a wrapped chronological fallback otherwise.
 - When the effective aggregate instruction set changes, its **Mid-Conversation System Message** includes the complete current ordered set and supersedes the prior aggregate value; when no ambient instructions remain, the message states that previously loaded instructions no longer apply.
@@ -133,6 +193,23 @@ The host-supplied environment overlay applied by the server when creating a PTY,
 - **Managed Tool Output Files** use globally unique names in one shared flat directory. Their absolute paths are readable and searchable by ordinary tools; other absolute paths remain outside Location-scoped filesystem authority.
 - Provider-executed tool results remain provider-native transcript facts outside generic Tool Registry bounding. Their context control requires provider-aware pruning or compaction because some providers require exact structured round-trip payloads.
 
+## Client contract architecture
+
+Semantic values that mean the same thing internally and publicly live in the lightweight Schema leaf. Core consumes Schema for domain behavior; Protocol composes Schema values into paths, payloads, envelopes, errors, cursors, and streams; Server imports both, hosts Protocol's exact groups, and owns protocol/domain adaptation. The root Promise client remains zero-Effect, `/effect` depends on Effect plus Schema and Protocol, and `@opencode-ai/sdk-next` composes the scoped in-process host above Client, Core, and Server.
+
+Shared public records are plain objects declared with `Schema.Struct`. A same-name inferred interface gives object records readable TypeScript signatures without constructors, prototypes, or nominal identity; unions retain explicit type aliases.
+
+Before stabilizing the client API:
+
+- Keep additional public schemas in Schema and additional network groups in Protocol; neither package may transitively load databases, Drizzle, Session execution, providers, watchers, native modules, or WASM.
+- Replace the transitional server-internal Session location middleware tag when the remaining location-scoped groups move to Protocol or gain a narrow request-location service contract.
+- Project the existing list response envelope to the stable client **Page** shape and enforce separate initial-query and cursor-continuation inputs without changing the hosted V2 wire contract.
+- Settle the stable consumer namespace (`session` versus the current beta `sessions`) and use an explicit codegen annotation if the consumer name should differ from the server group identifier.
+- Preserve V2 route paths, operation IDs, codecs, errors, middleware behavior, and OpenAPI output while making this change.
+- Preserve browser-safe `@opencode-ai/client` and `@opencode-ai/client/effect` bundles through import-boundary tests.
+- Define embedded-host placement before supporting multiple hosts over one database. Hosts that share durable Session storage must also share process-local Session execution coordination, or each host must receive isolated storage explicitly.
+- Keep an embedded request scope alive until any streamed response body finishes. The initial non-streaming Session surface does not exercise this lifetime boundary; Session and instance event streams must do so before joining the embedded client.
+
 ## Example dialogue
 
 > **Dev:** "The date changed while the session was active. Should the **Mid-Conversation System Message** say what the old date was?"

bun.lock

@@ -109,6 +109,27 @@
         "@typescript/native-preview": "catalog:",
       },
     },
+    "packages/client": {
+      "name": "@opencode-ai/client",
+      "dependencies": {
+        "@opencode-ai/protocol": "workspace:*",
+        "@opencode-ai/schema": "workspace:*",
+      },
+      "devDependencies": {
+        "@effect/platform-node": "catalog:",
+        "@opencode-ai/httpapi-codegen": "workspace:*",
+        "@tsconfig/bun": "catalog:",
+        "@types/bun": "catalog:",
+        "@typescript/native-preview": "catalog:",
+        "effect": "catalog:",
+      },
+      "peerDependencies": {
+        "effect": "4.0.0-beta.83",
+      },
+      "optionalPeers": [
+        "effect",
+      ],
+    },
     "packages/console/app": {
       "name": "@opencode-ai/console-app",
       "version": "1.17.9",
@@ -277,6 +298,7 @@
         "@opencode-ai/effect-sqlite-node": "workspace:*",
         "@opencode-ai/llm": "workspace:*",
         "@opencode-ai/plugin": "workspace:*",
+        "@opencode-ai/schema": "workspace:*",
         "@openrouter/ai-sdk-provider": "2.9.0",
         "@opentelemetry/api": "1.9.0",
         "@opentelemetry/context-async-hooks": "2.6.1",
@@ -476,6 +498,18 @@
         "effect": "4.0.0-beta.83",
       },
     },
+    "packages/httpapi-codegen": {
+      "name": "@opencode-ai/httpapi-codegen",
+      "dependencies": {
+        "effect": "catalog:",
+        "prettier": "3.6.2",
+      },
+      "devDependencies": {
+        "@tsconfig/bun": "catalog:",
+        "@types/bun": "catalog:",
+        "@typescript/native-preview": "catalog:",
+      },
+    },
     "packages/llm": {
       "name": "@opencode-ai/llm",
       "version": "1.17.9",
@@ -651,6 +685,30 @@
         "@opentui/solid",
       ],
     },
+    "packages/protocol": {
+      "name": "@opencode-ai/protocol",
+      "dependencies": {
+        "@opencode-ai/schema": "workspace:*",
+        "effect": "catalog:",
+      },
+      "devDependencies": {
+        "@tsconfig/bun": "catalog:",
+        "@types/bun": "catalog:",
+        "@typescript/native-preview": "catalog:",
+      },
+    },
+    "packages/schema": {
+      "name": "@opencode-ai/schema",
+      "dependencies": {
+        "@noble/hashes": "catalog:",
+        "effect": "catalog:",
+      },
+      "devDependencies": {
+        "@tsconfig/bun": "catalog:",
+        "@types/bun": "catalog:",
+        "@typescript/native-preview": "catalog:",
+      },
+    },
     "packages/script": {
       "name": "@opencode-ai/script",
       "dependencies": {
@@ -661,6 +719,20 @@
         "@types/semver": "^7.5.8",
       },
     },
+    "packages/sdk-next": {
+      "name": "@opencode-ai/sdk-next",
+      "dependencies": {
+        "@opencode-ai/client": "workspace:*",
+        "@opencode-ai/core": "workspace:*",
+        "@opencode-ai/server": "workspace:*",
+        "effect": "catalog:",
+      },
+      "devDependencies": {
+        "@tsconfig/bun": "catalog:",
+        "@types/bun": "catalog:",
+        "@typescript/native-preview": "catalog:",
+      },
+    },
     "packages/sdk/js": {
       "name": "@opencode-ai/sdk",
       "version": "1.17.9",
@@ -681,6 +753,7 @@
       "version": "1.17.9",
       "dependencies": {
         "@opencode-ai/core": "workspace:*",
+        "@opencode-ai/protocol": "workspace:*",
         "drizzle-orm": "catalog:",
         "effect": "catalog:",
       },
@@ -944,6 +1017,7 @@
     "@hono/zod-validator": "0.4.2",
     "@kobalte/core": "0.13.11",
     "@lydell/node-pty": "1.2.0-beta.12",
+    "@noble/hashes": "2.2.0",
     "@npmcli/arborist": "9.4.0",
     "@octokit/rest": "22.0.0",
     "@openauthjs/openauth": "0.0.0-20250322224806",
@@ -1774,6 +1848,8 @@
 
     "@opencode-ai/cli": ["@opencode-ai/cli@workspace:packages/cli"],
 
+    "@opencode-ai/client": ["@opencode-ai/client@workspace:packages/client"],
+
     "@opencode-ai/console-app": ["@opencode-ai/console-app@workspace:packages/console/app"],
 
     "@opencode-ai/console-core": ["@opencode-ai/console-core@workspace:packages/console/core"],
@@ -1800,14 +1876,22 @@
 
     "@opencode-ai/http-recorder": ["@opencode-ai/http-recorder@workspace:packages/http-recorder"],
 
+    "@opencode-ai/httpapi-codegen": ["@opencode-ai/httpapi-codegen@workspace:packages/httpapi-codegen"],
+
     "@opencode-ai/llm": ["@opencode-ai/llm@workspace:packages/llm"],
 
     "@opencode-ai/plugin": ["@opencode-ai/plugin@workspace:packages/plugin"],
 
+    "@opencode-ai/protocol": ["@opencode-ai/protocol@workspace:packages/protocol"],
+
+    "@opencode-ai/schema": ["@opencode-ai/schema@workspace:packages/schema"],
+
     "@opencode-ai/script": ["@opencode-ai/script@workspace:packages/script"],
 
     "@opencode-ai/sdk": ["@opencode-ai/sdk@workspace:packages/sdk/js"],
 
+    "@opencode-ai/sdk-next": ["@opencode-ai/sdk-next@workspace:packages/sdk-next"],
+
     "@opencode-ai/server": ["@opencode-ai/server@workspace:packages/server"],
 
     "@opencode-ai/slack": ["@opencode-ai/slack@workspace:packages/slack"],

package.json

@@ -34,6 +34,7 @@
       "@effect/platform-node": "4.0.0-beta.83",
       "@effect/sql-sqlite-bun": "4.0.0-beta.83",
       "@npmcli/arborist": "9.4.0",
+      "@noble/hashes": "2.2.0",
       "@types/bun": "1.3.13",
       "@types/cross-spawn": "6.0.6",
       "@octokit/rest": "22.0.0",

packages/client/README.md

@@ -0,0 +1,27 @@
+# @opencode-ai/client
+
+Private generation target for clients derived directly from OpenCode's authoritative Effect `HttpApi`.
+
+## Entrypoints
+
+- `@opencode-ai/client`: zero-Effect Promise client using `fetch`.
+- `@opencode-ai/client/effect`: rich Effect network client using an environment-provided `HttpClient`.
+
+The generated surface contains `sessions.list`, `create`, `get`, `switchAgent`, `switchModel`, `prompt`, `compact`, `wait`, and `context`. The server and generator consume the exact same hosted `SessionGroup`. Run `bun run generate` after changing that contract and `bun run check:generated` to detect committed-output drift.
+
+The Effect entrypoint uses canonical decoded values such as `Session.ID`, `Location.Ref`, and `Prompt`. These datatypes come from the lightweight `@opencode-ai/schema` package and are re-exported so callers depend only on the client surface. The authoritative `SessionGroup` lives in `@opencode-ai/protocol`; Server hosts that exact group and adapts it to Core.
+
+The Promise root remains structural and has no Core or Effect runtime dependency. `/effect` depends only on Effect, Schema, and Protocol and is browser-bundle safe. Bundle-boundary tests enforce both import graphs.
+
+Effect consumers construct canonical decoded inputs:
+
+```ts
+import { AbsolutePath, Location, OpenCode, Prompt } from "@opencode-ai/client/effect"
+
+const client = yield * OpenCode.make({ baseUrl: "https://opencode.example" })
+yield *
+  client.sessions.create({
+    location: Location.Ref.make({ directory: AbsolutePath.make("/workspace") }),
+  })
+yield * client.sessions.prompt({ sessionID, prompt: Prompt.make({ text: "Hello" }) })
+```

packages/client/package.json

@@ -0,0 +1,37 @@
+{
+  "$schema": "https://json.schemastore.org/package.json",
+  "name": "@opencode-ai/client",
+  "private": true,
+  "type": "module",
+  "license": "MIT",
+  "exports": {
+    ".": "./src/index.ts",
+    "./effect": "./src/effect.ts"
+  },
+  "scripts": {
+    "generate": "bun run script/build.ts",
+    "check:generated": "bun run generate && git diff --exit-code -- src/generated src/generated-effect",
+    "test": "bun test --timeout 5000",
+    "typecheck": "tsgo --noEmit"
+  },
+  "dependencies": {
+    "@opencode-ai/schema": "workspace:*",
+    "@opencode-ai/protocol": "workspace:*"
+  },
+  "peerDependencies": {
+    "effect": "4.0.0-beta.83"
+  },
+  "peerDependenciesMeta": {
+    "effect": {
+      "optional": true
+    }
+  },
+  "devDependencies": {
+    "@effect/platform-node": "catalog:",
+    "@opencode-ai/httpapi-codegen": "workspace:*",
+    "@tsconfig/bun": "catalog:",
+    "@types/bun": "catalog:",
+    "@typescript/native-preview": "catalog:",
+    "effect": "catalog:"
+  }
+}

packages/client/script/build.ts

@@ -0,0 +1,26 @@
+import { NodeFileSystem } from "@effect/platform-node"
+import { SessionGroup } from "@opencode-ai/protocol/session"
+import { compile, emitEffectImported, emitPromise, write } from "@opencode-ai/httpapi-codegen"
+import { Effect } from "effect"
+import { HttpApi } from "effect/unstable/httpapi"
+import { fileURLToPath } from "url"
+
+const contract = compile(HttpApi.make("opencode-client").add(SessionGroup), {
+  groupNames: { "server.session": "sessions" },
+})
+
+await Effect.runPromise(
+  Effect.all(
+    [
+      write(emitPromise(contract), fileURLToPath(new URL("../src/generated", import.meta.url))),
+      write(
+        emitEffectImported(contract, {
+          module: "@opencode-ai/protocol/session",
+          group: "SessionGroup",
+        }),
+        fileURLToPath(new URL("../src/generated-effect", import.meta.url)),
+      ),
+    ],
+    { concurrency: 2, discard: true },
+  ).pipe(Effect.provide(NodeFileSystem.layer)),
+)

packages/client/src/effect.ts

@@ -0,0 +1,12 @@
+// TODO: Keep additional network capabilities inside Schema and Protocol as the client grows; /effect must never import
+// Core or Server. Preserve these datatype exports so internal model reorganizations do not require caller migrations.
+export * from "./generated-effect/index"
+export { Agent } from "@opencode-ai/schema/agent"
+export { Location } from "@opencode-ai/schema/location"
+export { Model } from "@opencode-ai/schema/model"
+export { Provider } from "@opencode-ai/schema/provider"
+export { AbsolutePath, RelativePath } from "@opencode-ai/schema/schema"
+export { Session } from "@opencode-ai/schema/session"
+export { SessionInput } from "@opencode-ai/schema/session-input"
+export { SessionMessage } from "@opencode-ai/schema/session-message"
+export { Prompt } from "@opencode-ai/schema/prompt"

packages/client/src/generated-effect/.httpapi-codegen.json

@@ -0,0 +1,5 @@
+[
+  "client-error.ts",
+  "client.ts",
+  "index.ts"
+]

packages/client/src/generated-effect/client-error.ts

@@ -0,0 +1,5 @@
+import { Schema } from "effect"
+
+export class ClientError extends Schema.TaggedErrorClass<ClientError>()("ClientError", {
+  cause: Schema.Defect(),
+}) {}

packages/client/src/generated-effect/client.ts

@@ -0,0 +1,136 @@
+// Generated by @opencode-ai/httpapi-codegen. Do not edit.
+import { Effect, Schema } from "effect"
+import { Sse } from "effect/unstable/encoding"
+import { HttpClientError } from "effect/unstable/http"
+import { HttpApi, HttpApiClient } from "effect/unstable/httpapi"
+import { SessionGroup } from "@opencode-ai/protocol/session"
+import { ClientError } from "./client-error"
+
+const Api = HttpApi.make("generated").add(SessionGroup)
+
+type RawClient = HttpApiClient.ForApi<typeof Api>
+
+const mapClientError = <E>(error: E) =>
+  HttpClientError.isHttpClientError(error) || Schema.isSchemaError(error) || Sse.Retry.is(error)
+    ? new ClientError({ cause: error })
+    : error
+
+type Endpoint0_0Request = Parameters<RawClient["server.session"]["session.list"]>[0]
+type Endpoint0_0Input = {
+  readonly workspace?: Endpoint0_0Request["query"]["workspace"]
+  readonly limit?: Endpoint0_0Request["query"]["limit"]
+  readonly order?: Endpoint0_0Request["query"]["order"]
+  readonly search?: Endpoint0_0Request["query"]["search"]
+  readonly directory?: Endpoint0_0Request["query"]["directory"]
+  readonly project?: Endpoint0_0Request["query"]["project"]
+  readonly subpath?: Endpoint0_0Request["query"]["subpath"]
+  readonly cursor?: Endpoint0_0Request["query"]["cursor"]
+}
+const Endpoint0_0 = (raw: RawClient["server.session"]) => (input?: Endpoint0_0Input) =>
+  raw["session.list"]({
+    query: {
+      workspace: input?.workspace,
+      limit: input?.limit,
+      order: input?.order,
+      search: input?.search,
+      directory: input?.directory,
+      project: input?.project,
+      subpath: input?.subpath,
+      cursor: input?.cursor,
+    },
+  }).pipe(Effect.mapError(mapClientError))
+
+type Endpoint0_1Request = Parameters<RawClient["server.session"]["session.create"]>[0]
+type Endpoint0_1Input = {
+  readonly id?: Endpoint0_1Request["payload"]["id"]
+  readonly agent?: Endpoint0_1Request["payload"]["agent"]
+  readonly model?: Endpoint0_1Request["payload"]["model"]
+  readonly location?: Endpoint0_1Request["payload"]["location"]
+}
+const Endpoint0_1 = (raw: RawClient["server.session"]) => (input?: Endpoint0_1Input) =>
+  raw["session.create"]({
+    payload: { id: input?.id, agent: input?.agent, model: input?.model, location: input?.location },
+  }).pipe(
+    Effect.mapError(mapClientError),
+    Effect.map((value) => value.data),
+  )
+
+type Endpoint0_2Request = Parameters<RawClient["server.session"]["session.get"]>[0]
+type Endpoint0_2Input = { readonly sessionID: Endpoint0_2Request["params"]["sessionID"] }
+const Endpoint0_2 = (raw: RawClient["server.session"]) => (input: Endpoint0_2Input) =>
+  raw["session.get"]({ params: { sessionID: input.sessionID } }).pipe(
+    Effect.mapError(mapClientError),
+    Effect.map((value) => value.data),
+  )
+
+type Endpoint0_3Request = Parameters<RawClient["server.session"]["session.switchAgent"]>[0]
+type Endpoint0_3Input = {
+  readonly sessionID: Endpoint0_3Request["params"]["sessionID"]
+  readonly agent: Endpoint0_3Request["payload"]["agent"]
+}
+const Endpoint0_3 = (raw: RawClient["server.session"]) => (input: Endpoint0_3Input) =>
+  raw["session.switchAgent"]({ params: { sessionID: input.sessionID }, payload: { agent: input.agent } }).pipe(
+    Effect.mapError(mapClientError),
+  )
+
+type Endpoint0_4Request = Parameters<RawClient["server.session"]["session.switchModel"]>[0]
+type Endpoint0_4Input = {
+  readonly sessionID: Endpoint0_4Request["params"]["sessionID"]
+  readonly model: Endpoint0_4Request["payload"]["model"]
+}
+const Endpoint0_4 = (raw: RawClient["server.session"]) => (input: Endpoint0_4Input) =>
+  raw["session.switchModel"]({ params: { sessionID: input.sessionID }, payload: { model: input.model } }).pipe(
+    Effect.mapError(mapClientError),
+  )
+
+type Endpoint0_5Request = Parameters<RawClient["server.session"]["session.prompt"]>[0]
+type Endpoint0_5Input = {
+  readonly sessionID: Endpoint0_5Request["params"]["sessionID"]
+  readonly id?: Endpoint0_5Request["payload"]["id"]
+  readonly prompt: Endpoint0_5Request["payload"]["prompt"]
+  readonly delivery?: Endpoint0_5Request["payload"]["delivery"]
+  readonly resume?: Endpoint0_5Request["payload"]["resume"]
+}
+const Endpoint0_5 = (raw: RawClient["server.session"]) => (input: Endpoint0_5Input) =>
+  raw["session.prompt"]({
+    params: { sessionID: input.sessionID },
+    payload: { id: input.id, prompt: input.prompt, delivery: input.delivery, resume: input.resume },
+  }).pipe(
+    Effect.mapError(mapClientError),
+    Effect.map((value) => value.data),
+  )
+
+type Endpoint0_6Request = Parameters<RawClient["server.session"]["session.compact"]>[0]
+type Endpoint0_6Input = { readonly sessionID: Endpoint0_6Request["params"]["sessionID"] }
+const Endpoint0_6 = (raw: RawClient["server.session"]) => (input: Endpoint0_6Input) =>
+  raw["session.compact"]({ params: { sessionID: input.sessionID } }).pipe(Effect.mapError(mapClientError))
+
+type Endpoint0_7Request = Parameters<RawClient["server.session"]["session.wait"]>[0]
+type Endpoint0_7Input = { readonly sessionID: Endpoint0_7Request["params"]["sessionID"] }
+const Endpoint0_7 = (raw: RawClient["server.session"]) => (input: Endpoint0_7Input) =>
+  raw["session.wait"]({ params: { sessionID: input.sessionID } }).pipe(Effect.mapError(mapClientError))
+
+type Endpoint0_8Request = Parameters<RawClient["server.session"]["session.context"]>[0]
+type Endpoint0_8Input = { readonly sessionID: Endpoint0_8Request["params"]["sessionID"] }
+const Endpoint0_8 = (raw: RawClient["server.session"]) => (input: Endpoint0_8Input) =>
+  raw["session.context"]({ params: { sessionID: input.sessionID } }).pipe(
+    Effect.mapError(mapClientError),
+    Effect.map((value) => value.data),
+  )
+
+const adaptGroup0 = (raw: RawClient["server.session"]) => ({
+  list: Endpoint0_0(raw),
+  create: Endpoint0_1(raw),
+  get: Endpoint0_2(raw),
+  switchAgent: Endpoint0_3(raw),
+  switchModel: Endpoint0_4(raw),
+  prompt: Endpoint0_5(raw),
+  compact: Endpoint0_6(raw),
+  wait: Endpoint0_7(raw),
+  context: Endpoint0_8(raw),
+})
+
+const adaptClient = (raw: RawClient) => ({ sessions: adaptGroup0(raw["server.session"]) })
+
+export const make = (options?: { readonly baseUrl?: URL | string }) =>
+  HttpApiClient.make(Api, options).pipe(Effect.map(adaptClient))

packages/client/src/generated-effect/index.ts

@@ -0,0 +1,2 @@
+export { ClientError } from "./client-error"
+export * as OpenCode from "./client"

packages/client/src/generated/.httpapi-codegen.json

@@ -0,0 +1,6 @@
+[
+  "client-error.ts",
+  "client.ts",
+  "index.ts",
+  "types.ts"
+]

packages/client/src/generated/client-error.ts

@@ -0,0 +1,11 @@
+export type ClientErrorReason = "Transport" | "UnexpectedStatus" | "UnsupportedContentType" | "MalformedResponse"
+
+export class ClientError extends Error {
+  override readonly name = "ClientError"
+  constructor(
+    readonly reason: ClientErrorReason,
+    options?: ErrorOptions,
+  ) {
+    super(reason, options)
+  }
+}

packages/client/src/generated/client.ts

@@ -0,0 +1,309 @@
+import type {
+  SessionsListInput,
+  SessionsListOutput,
+  SessionsCreateInput,
+  SessionsCreateOutput,
+  SessionsGetInput,
+  SessionsGetOutput,
+  SessionsSwitchAgentInput,
+  SessionsSwitchAgentOutput,
+  SessionsSwitchModelInput,
+  SessionsSwitchModelOutput,
+  SessionsPromptInput,
+  SessionsPromptOutput,
+  SessionsCompactInput,
+  SessionsCompactOutput,
+  SessionsWaitInput,
+  SessionsWaitOutput,
+  SessionsContextInput,
+  SessionsContextOutput,
+} from "./types"
+import { ClientError } from "./client-error"
+
+export interface ClientOptions {
+  readonly baseUrl: string
+  readonly fetch?: typeof globalThis.fetch
+  readonly headers?: HeadersInit
+}
+
+export interface RequestOptions {
+  readonly signal?: AbortSignal
+  readonly headers?: HeadersInit
+}
+
+interface RequestDescriptor {
+  readonly method: string
+  readonly path: string
+  readonly query?: Record<string, unknown>
+  readonly headers?: Record<string, unknown>
+  readonly body?: unknown
+  readonly successStatus: number
+  readonly declaredStatuses: ReadonlyArray<number>
+  readonly empty: boolean
+}
+
+export function make(options: ClientOptions) {
+  const fetch = options.fetch ?? globalThis.fetch
+
+  const prepare = (descriptor: RequestDescriptor, requestOptions?: RequestOptions) => {
+    const url = new URL(descriptor.path, options.baseUrl)
+    for (const [key, value] of Object.entries(descriptor.query ?? {})) appendQuery(url.searchParams, key, value)
+    const headers = new Headers(options.headers)
+    for (const [key, value] of Object.entries(descriptor.headers ?? {})) {
+      if (value !== undefined && value !== null) headers.set(key, String(value))
+    }
+    for (const [key, value] of new Headers(requestOptions?.headers)) headers.set(key, value)
+    if (descriptor.body !== undefined && !headers.has("content-type")) headers.set("content-type", "application/json")
+    return {
+      url,
+      init: {
+        method: descriptor.method,
+        signal: requestOptions?.signal,
+        headers,
+        body: descriptor.body === undefined ? undefined : JSON.stringify(descriptor.body),
+      } satisfies RequestInit,
+    }
+  }
+
+  const execute = async (descriptor: RequestDescriptor, requestOptions?: RequestOptions) => {
+    try {
+      const prepared = prepare(descriptor, requestOptions)
+      return await fetch(prepared.url, prepared.init)
+    } catch (cause) {
+      throw new ClientError("Transport", { cause })
+    }
+  }
+
+  const responseError = async (response: Response, descriptor: RequestDescriptor): Promise<never> => {
+    if (descriptor.declaredStatuses.includes(response.status)) throw await json(response)
+    try {
+      await response.body?.cancel()
+    } catch {}
+    throw new ClientError("UnexpectedStatus", { cause: { status: response.status } })
+  }
+
+  const request = async <A>(descriptor: RequestDescriptor, requestOptions?: RequestOptions): Promise<A> => {
+    const response = await execute(descriptor, requestOptions)
+    if (response.status !== descriptor.successStatus) return responseError(response, descriptor)
+    if (descriptor.empty) {
+      try {
+        await response.body?.cancel()
+      } catch {}
+      return undefined as A
+    }
+    return (await json(response)) as A
+  }
+
+  const sse = <A>(descriptor: RequestDescriptor, requestOptions?: RequestOptions): AsyncIterable<A> => ({
+    async *[Symbol.asyncIterator]() {
+      const response = await execute(descriptor, requestOptions)
+      if (response.status !== descriptor.successStatus) await responseError(response, descriptor)
+      if (!isContentType(response, "text/event-stream")) {
+        try {
+          await response.body?.cancel()
+        } catch {}
+        throw new ClientError("UnsupportedContentType")
+      }
+      if (response.body === null) throw new ClientError("MalformedResponse")
+      const reader = response.body.getReader()
+      const decoder = new TextDecoder()
+      let buffer = ""
+      try {
+        while (true) {
+          let next
+          try {
+            next = await reader.read()
+          } catch (cause) {
+            throw new ClientError("Transport", { cause })
+          }
+          buffer += decoder.decode(next.value, { stream: !next.done })
+          if (buffer.length > 1_048_576) throw new ClientError("MalformedResponse")
+          const trailingCarriageReturn = !next.done && buffer.endsWith("\r")
+          if (trailingCarriageReturn) buffer = buffer.slice(0, -1)
+          buffer = buffer.replaceAll("\r\n", "\n").replaceAll("\r", "\n")
+          if (trailingCarriageReturn) buffer += "\r"
+          if (next.done && buffer !== "") buffer += "\n\n"
+          let boundary = buffer.indexOf("\n\n")
+          while (boundary >= 0) {
+            const block = buffer.slice(0, boundary)
+            buffer = buffer.slice(boundary + 2)
+            const data = block
+              .split("\n")
+              .flatMap((line) => (line.startsWith("data:") ? [line.slice(5).trimStart()] : []))
+              .join("\n")
+            if (data !== "") {
+              try {
+                yield JSON.parse(data) as A
+              } catch (cause) {
+                throw new ClientError("MalformedResponse", { cause })
+              }
+            }
+            boundary = buffer.indexOf("\n\n")
+          }
+          if (next.done) return
+        }
+      } finally {
+        try {
+          await reader.cancel()
+        } catch {}
+        reader.releaseLock()
+      }
+    },
+  })
+
+  return {
+    sessions: {
+      list: (input?: SessionsListInput, requestOptions?: RequestOptions) =>
+        request<SessionsListOutput>(
+          {
+            method: "GET",
+            path: `/api/session`,
+            query: {
+              workspace: input?.workspace,
+              limit: input?.limit,
+              order: input?.order,
+              search: input?.search,
+              directory: input?.directory,
+              project: input?.project,
+              subpath: input?.subpath,
+              cursor: input?.cursor,
+            },
+            successStatus: 200,
+            declaredStatuses: [400, 401],
+            empty: false,
+          },
+          requestOptions,
+        ),
+      create: (input?: SessionsCreateInput, requestOptions?: RequestOptions) =>
+        request<{ readonly data: SessionsCreateOutput }>(
+          {
+            method: "POST",
+            path: `/api/session`,
+            body: { id: input?.id, agent: input?.agent, model: input?.model, location: input?.location },
+            successStatus: 200,
+            declaredStatuses: [400, 401],
+            empty: false,
+          },
+          requestOptions,
+        ).then((value) => value.data),
+      get: (input: SessionsGetInput, requestOptions?: RequestOptions) =>
+        request<{ readonly data: SessionsGetOutput }>(
+          {
+            method: "GET",
+            path: `/api/session/${encodeURIComponent(input.sessionID)}`,
+            successStatus: 200,
+            declaredStatuses: [400, 404, 401],
+            empty: false,
+          },
+          requestOptions,
+        ).then((value) => value.data),
+      switchAgent: (input: SessionsSwitchAgentInput, requestOptions?: RequestOptions) =>
+        request<SessionsSwitchAgentOutput>(
+          {
+            method: "POST",
+            path: `/api/session/${encodeURIComponent(input.sessionID)}/agent`,
+            body: { agent: input.agent },
+            successStatus: 204,
+            declaredStatuses: [400, 404, 401],
+            empty: true,
+          },
+          requestOptions,
+        ),
+      switchModel: (input: SessionsSwitchModelInput, requestOptions?: RequestOptions) =>
+        request<SessionsSwitchModelOutput>(
+          {
+            method: "POST",
+            path: `/api/session/${encodeURIComponent(input.sessionID)}/model`,
+            body: { model: input.model },
+            successStatus: 204,
+            declaredStatuses: [400, 404, 401],
+            empty: true,
+          },
+          requestOptions,
+        ),
+      prompt: (input: SessionsPromptInput, requestOptions?: RequestOptions) =>
+        request<{ readonly data: SessionsPromptOutput }>(
+          {
+            method: "POST",
+            path: `/api/session/${encodeURIComponent(input.sessionID)}/prompt`,
+            body: { id: input.id, prompt: input.prompt, delivery: input.delivery, resume: input.resume },
+            successStatus: 200,
+            declaredStatuses: [409, 400, 404, 401],
+            empty: false,
+          },
+          requestOptions,
+        ).then((value) => value.data),
+      compact: (input: SessionsCompactInput, requestOptions?: RequestOptions) =>
+        request<SessionsCompactOutput>(
+          {
+            method: "POST",
+            path: `/api/session/${encodeURIComponent(input.sessionID)}/compact`,
+            successStatus: 204,
+            declaredStatuses: [404, 503, 401, 400],
+            empty: true,
+          },
+          requestOptions,
+        ),
+      wait: (input: SessionsWaitInput, requestOptions?: RequestOptions) =>
+        request<SessionsWaitOutput>(
+          {
+            method: "POST",
+            path: `/api/session/${encodeURIComponent(input.sessionID)}/wait`,
+            successStatus: 204,
+            declaredStatuses: [404, 503, 401, 400],
+            empty: true,
+          },
+          requestOptions,
+        ),
+      context: (input: SessionsContextInput, requestOptions?: RequestOptions) =>
+        request<{ readonly data: SessionsContextOutput }>(
+          {
+            method: "GET",
+            path: `/api/session/${encodeURIComponent(input.sessionID)}/context`,
+            successStatus: 200,
+            declaredStatuses: [404, 401, 500, 400],
+            empty: false,
+          },
+          requestOptions,
+        ).then((value) => value.data),
+    },
+  }
+}
+
+function appendQuery(params: URLSearchParams, key: string, value: unknown): void {
+  if (value === undefined || value === null) return
+  if (Array.isArray(value)) {
+    for (const item of value) appendQuery(params, key, item)
+    return
+  }
+  if (typeof value === "object") {
+    for (const [child, item] of Object.entries(value)) appendQuery(params, `${key}[${child}]`, item)
+    return
+  }
+  params.append(key, String(value))
+}
+
+async function json(response: Response): Promise<unknown> {
+  if (!isContentType(response, "application/json") && !response.headers.get("content-type")?.includes("+json")) {
+    try {
+      await response.body?.cancel()
+    } catch {}
+    throw new ClientError("UnsupportedContentType")
+  }
+  let text: string
+  try {
+    text = await response.text()
+  } catch (cause) {
+    throw new ClientError("Transport", { cause })
+  }
+  if (text === "") throw new ClientError("MalformedResponse")
+  try {
+    return JSON.parse(text)
+  } catch (cause) {
+    throw new ClientError("MalformedResponse", { cause })
+  }
+}
+
+function isContentType(response: Response, expected: string) {
+  return response.headers.get("content-type")?.split(";", 1)[0]?.trim().toLowerCase() === expected
+}

packages/client/src/generated/index.ts

@@ -0,0 +1,3 @@
+export { ClientError, type ClientErrorReason } from "./client-error"
+export * as OpenCode from "./client"
+export * from "./types"

packages/client/src/generated/types.ts

@@ -0,0 +1,555 @@
+export type JsonValue =
+  | null
+  | boolean
+  | number
+  | string
+  | ReadonlyArray<JsonValue>
+  | { readonly [key: string]: JsonValue }
+
+export type InvalidCursorError = { readonly _tag: "InvalidCursorError"; readonly message: string }
+export const isInvalidCursorError = (value: unknown): value is InvalidCursorError =>
+  typeof value === "object" && value !== null && "_tag" in value && value._tag === "InvalidCursorError"
+
+export type InvalidRequestError = {
+  readonly _tag: "InvalidRequestError"
+  readonly message: string
+  readonly kind?: string | undefined
+  readonly field?: string | undefined
+}
+export const isInvalidRequestError = (value: unknown): value is InvalidRequestError =>
+  typeof value === "object" && value !== null && "_tag" in value && value._tag === "InvalidRequestError"
+
+export type UnauthorizedError = { readonly _tag: "UnauthorizedError"; readonly message: string }
+export const isUnauthorizedError = (value: unknown): value is UnauthorizedError =>
+  typeof value === "object" && value !== null && "_tag" in value && value._tag === "UnauthorizedError"
+
+export type SessionNotFoundError = {
+  readonly _tag: "SessionNotFoundError"
+  readonly sessionID: string
+  readonly message: string
+}
+export const isSessionNotFoundError = (value: unknown): value is SessionNotFoundError =>
+  typeof value === "object" && value !== null && "_tag" in value && value._tag === "SessionNotFoundError"
+
+export type ConflictError = {
+  readonly _tag: "ConflictError"
+  readonly message: string
+  readonly resource?: string | undefined
+}
+export const isConflictError = (value: unknown): value is ConflictError =>
+  typeof value === "object" && value !== null && "_tag" in value && value._tag === "ConflictError"
+
+export type ServiceUnavailableError = {
+  readonly _tag: "ServiceUnavailableError"
+  readonly message: string
+  readonly service?: string | undefined
+}
+export const isServiceUnavailableError = (value: unknown): value is ServiceUnavailableError =>
+  typeof value === "object" && value !== null && "_tag" in value && value._tag === "ServiceUnavailableError"
+
+export type UnknownError = {
+  readonly _tag: "UnknownError"
+  readonly message: string
+  readonly ref?: string | undefined
+}
+export const isUnknownError = (value: unknown): value is UnknownError =>
+  typeof value === "object" && value !== null && "_tag" in value && value._tag === "UnknownError"
+
+export type SessionsListInput = {
+  readonly workspace?: {
+    readonly workspace?: string | undefined
+    readonly limit?: string | undefined
+    readonly order?: "asc" | "desc" | undefined
+    readonly search?: string | undefined
+    readonly directory?: string | undefined
+    readonly project?: string | undefined
+    readonly subpath?: string | undefined
+    readonly cursor?: string | undefined
+  }["workspace"]
+  readonly limit?: {
+    readonly workspace?: string | undefined
+    readonly limit?: string | undefined
+    readonly order?: "asc" | "desc" | undefined
+    readonly search?: string | undefined
+    readonly directory?: string | undefined
+    readonly project?: string | undefined
+    readonly subpath?: string | undefined
+    readonly cursor?: string | undefined
+  }["limit"]
+  readonly order?: {
+    readonly workspace?: string | undefined
+    readonly limit?: string | undefined
+    readonly order?: "asc" | "desc" | undefined
+    readonly search?: string | undefined
+    readonly directory?: string | undefined
+    readonly project?: string | undefined
+    readonly subpath?: string | undefined
+    readonly cursor?: string | undefined
+  }["order"]
+  readonly search?: {
+    readonly workspace?: string | undefined
+    readonly limit?: string | undefined
+    readonly order?: "asc" | "desc" | undefined
+    readonly search?: string | undefined
+    readonly directory?: string | undefined
+    readonly project?: string | undefined
+    readonly subpath?: string | undefined
+    readonly cursor?: string | undefined
+  }["search"]
+  readonly directory?: {
+    readonly workspace?: string | undefined
+    readonly limit?: string | undefined
+    readonly order?: "asc" | "desc" | undefined
+    readonly search?: string | undefined
+    readonly directory?: string | undefined
+    readonly project?: string | undefined
+    readonly subpath?: string | undefined
+    readonly cursor?: string | undefined
+  }["directory"]
+  readonly project?: {
+    readonly workspace?: string | undefined
+    readonly limit?: string | undefined
+    readonly order?: "asc" | "desc" | undefined
+    readonly search?: string | undefined
+    readonly directory?: string | undefined
+    readonly project?: string | undefined
+    readonly subpath?: string | undefined
+    readonly cursor?: string | undefined
+  }["project"]
+  readonly subpath?: {
+    readonly workspace?: string | undefined
+    readonly limit?: string | undefined
+    readonly order?: "asc" | "desc" | undefined
+    readonly search?: string | undefined
+    readonly directory?: string | undefined
+    readonly project?: string | undefined
+    readonly subpath?: string | undefined
+    readonly cursor?: string | undefined
+  }["subpath"]
+  readonly cursor?: {
+    readonly workspace?: string | undefined
+    readonly limit?: string | undefined
+    readonly order?: "asc" | "desc" | undefined
+    readonly search?: string | undefined
+    readonly directory?: string | undefined
+    readonly project?: string | undefined
+    readonly subpath?: string | undefined
+    readonly cursor?: string | undefined
+  }["cursor"]
+}
+
+export type SessionsListOutput = {
+  readonly data: ReadonlyArray<{
+    readonly id: string
+    readonly parentID?: string
+    readonly projectID: string
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string | null } | null
+    readonly cost: number
+    readonly tokens: {
+      readonly input: number
+      readonly output: number
+      readonly reasoning: number
+      readonly cache: { readonly read: number; readonly write: number }
+    }
+    readonly time: { readonly created: number; readonly updated: number; readonly archived?: number | null }
+    readonly title: string
+    readonly location: { readonly directory: string; readonly workspaceID?: string | null }
+    readonly subpath?: string | null
+  }>
+  readonly cursor: { readonly previous?: string | null; readonly next?: string | null }
+}
+
+export type SessionsCreateInput = {
+  readonly id?: {
+    readonly id?: string | undefined
+    readonly agent?: string | undefined
+    readonly model?:
+      | { readonly id: string; readonly providerID: string; readonly variant?: string | undefined }
+      | undefined
+    readonly location?: { readonly directory: string; readonly workspaceID?: string | undefined } | undefined
+  }["id"]
+  readonly agent?: {
+    readonly id?: string | undefined
+    readonly agent?: string | undefined
+    readonly model?:
+      | { readonly id: string; readonly providerID: string; readonly variant?: string | undefined }
+      | undefined
+    readonly location?: { readonly directory: string; readonly workspaceID?: string | undefined } | undefined
+  }["agent"]
+  readonly model?: {
+    readonly id?: string | undefined
+    readonly agent?: string | undefined
+    readonly model?:
+      | { readonly id: string; readonly providerID: string; readonly variant?: string | undefined }
+      | undefined
+    readonly location?: { readonly directory: string; readonly workspaceID?: string | undefined } | undefined
+  }["model"]
+  readonly location?: {
+    readonly id?: string | undefined
+    readonly agent?: string | undefined
+    readonly model?:
+      | { readonly id: string; readonly providerID: string; readonly variant?: string | undefined }
+      | undefined
+    readonly location?: { readonly directory: string; readonly workspaceID?: string | undefined } | undefined
+  }["location"]
+}
+
+export type SessionsCreateOutput = {
+  readonly data: {
+    readonly id: string
+    readonly parentID?: string
+    readonly projectID: string
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string | null } | null
+    readonly cost: number
+    readonly tokens: {
+      readonly input: number
+      readonly output: number
+      readonly reasoning: number
+      readonly cache: { readonly read: number; readonly write: number }
+    }
+    readonly time: { readonly created: number; readonly updated: number; readonly archived?: number | null }
+    readonly title: string
+    readonly location: { readonly directory: string; readonly workspaceID?: string | null }
+    readonly subpath?: string | null
+  }
+}["data"]
+
+export type SessionsGetInput = { readonly sessionID: { readonly sessionID: string }["sessionID"] }
+
+export type SessionsGetOutput = {
+  readonly data: {
+    readonly id: string
+    readonly parentID?: string
+    readonly projectID: string
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string | null } | null
+    readonly cost: number
+    readonly tokens: {
+      readonly input: number
+      readonly output: number
+      readonly reasoning: number
+      readonly cache: { readonly read: number; readonly write: number }
+    }
+    readonly time: { readonly created: number; readonly updated: number; readonly archived?: number | null }
+    readonly title: string
+    readonly location: { readonly directory: string; readonly workspaceID?: string | null }
+    readonly subpath?: string | null
+  }
+}["data"]
+
+export type SessionsSwitchAgentInput = {
+  readonly sessionID: { readonly sessionID: string }["sessionID"]
+  readonly agent: { readonly agent: string }["agent"]
+}
+
+export type SessionsSwitchAgentOutput = void
+
+export type SessionsSwitchModelInput = {
+  readonly sessionID: { readonly sessionID: string }["sessionID"]
+  readonly model: {
+    readonly model: { readonly id: string; readonly providerID: string; readonly variant?: string | undefined }
+  }["model"]
+}
+
+export type SessionsSwitchModelOutput = void
+
+export type SessionsPromptInput = {
+  readonly sessionID: { readonly sessionID: string }["sessionID"]
+  readonly id?: {
+    readonly id?: string | undefined
+    readonly prompt: {
+      readonly text: string
+      readonly files?:
+        | ReadonlyArray<{
+            readonly uri: string
+            readonly mime: string
+            readonly name?: string | undefined
+            readonly description?: string | undefined
+            readonly source?: { readonly start: number; readonly end: number; readonly text: string } | undefined
+          }>
+        | undefined
+      readonly agents?:
+        | ReadonlyArray<{
+            readonly name: string
+            readonly source?: { readonly start: number; readonly end: number; readonly text: string } | undefined
+          }>
+        | undefined
+    }
+    readonly delivery?: "steer" | "queue" | undefined
+    readonly resume?: boolean | undefined
+  }["id"]
+  readonly prompt: {
+    readonly id?: string | undefined
+    readonly prompt: {
+      readonly text: string
+      readonly files?:
+        | ReadonlyArray<{
+            readonly uri: string
+            readonly mime: string
+            readonly name?: string | undefined
+            readonly description?: string | undefined
+            readonly source?: { readonly start: number; readonly end: number; readonly text: string } | undefined
+          }>
+        | undefined
+      readonly agents?:
+        | ReadonlyArray<{
+            readonly name: string
+            readonly source?: { readonly start: number; readonly end: number; readonly text: string } | undefined
+          }>
+        | undefined
+    }
+    readonly delivery?: "steer" | "queue" | undefined
+    readonly resume?: boolean | undefined
+  }["prompt"]
+  readonly delivery?: {
+    readonly id?: string | undefined
+    readonly prompt: {
+      readonly text: string
+      readonly files?:
+        | ReadonlyArray<{
+            readonly uri: string
+            readonly mime: string
+            readonly name?: string | undefined
+            readonly description?: string | undefined
+            readonly source?: { readonly start: number; readonly end: number; readonly text: string } | undefined
+          }>
+        | undefined
+      readonly agents?:
+        | ReadonlyArray<{
+            readonly name: string
+            readonly source?: { readonly start: number; readonly end: number; readonly text: string } | undefined
+          }>
+        | undefined
+    }
+    readonly delivery?: "steer" | "queue" | undefined
+    readonly resume?: boolean | undefined
+  }["delivery"]
+  readonly resume?: {
+    readonly id?: string | undefined
+    readonly prompt: {
+      readonly text: string
+      readonly files?:
+        | ReadonlyArray<{
+            readonly uri: string
+            readonly mime: string
+            readonly name?: string | undefined
+            readonly description?: string | undefined
+            readonly source?: { readonly start: number; readonly end: number; readonly text: string } | undefined
+          }>
+        | undefined
+      readonly agents?:
+        | ReadonlyArray<{
+            readonly name: string
+            readonly source?: { readonly start: number; readonly end: number; readonly text: string } | undefined
+          }>
+        | undefined
+    }
+    readonly delivery?: "steer" | "queue" | undefined
+    readonly resume?: boolean | undefined
+  }["resume"]
+}
+
+export type SessionsPromptOutput = {
+  readonly data: {
+    readonly admittedSeq: number
+    readonly id: string
+    readonly sessionID: string
+    readonly prompt: {
+      readonly text: string
+      readonly files?: ReadonlyArray<{
+        readonly uri: string
+        readonly mime: string
+        readonly name?: string | null
+        readonly description?: string | null
+        readonly source?: { readonly start: number; readonly end: number; readonly text: string } | null
+      }> | null
+      readonly agents?: ReadonlyArray<{
+        readonly name: string
+        readonly source?: { readonly start: number; readonly end: number; readonly text: string } | null
+      }> | null
+    }
+    readonly delivery: "steer" | "queue"
+    readonly timeCreated: number
+    readonly promotedSeq?: number | null
+  }
+}["data"]
+
+export type SessionsCompactInput = { readonly sessionID: { readonly sessionID: string }["sessionID"] }
+
+export type SessionsCompactOutput = void
+
+export type SessionsWaitInput = { readonly sessionID: { readonly sessionID: string }["sessionID"] }
+
+export type SessionsWaitOutput = void
+
+export type SessionsContextInput = { readonly sessionID: { readonly sessionID: string }["sessionID"] }
+
+export type SessionsContextOutput = {
+  readonly data: ReadonlyArray<
+    | {
+        readonly id: string
+        readonly metadata?: { readonly [x: string]: JsonValue } | null
+        readonly time: { readonly created: number }
+        readonly type: "agent-switched"
+        readonly agent: string
+      }
+    | {
+        readonly id: string
+        readonly metadata?: { readonly [x: string]: JsonValue } | null
+        readonly time: { readonly created: number }
+        readonly type: "model-switched"
+        readonly model: { readonly id: string; readonly providerID: string; readonly variant?: string | null }
+      }
+    | {
+        readonly id: string
+        readonly metadata?: { readonly [x: string]: JsonValue } | null
+        readonly time: { readonly created: number }
+        readonly text: string
+        readonly files?: ReadonlyArray<{
+          readonly uri: string
+          readonly mime: string
+          readonly name?: string | null
+          readonly description?: string | null
+          readonly source?: { readonly start: number; readonly end: number; readonly text: string } | null
+        }> | null
+        readonly agents?: ReadonlyArray<{
+          readonly name: string
+          readonly source?: { readonly start: number; readonly end: number; readonly text: string } | null
+        }> | null
+        readonly type: "user"
+      }
+    | {
+        readonly id: string
+        readonly metadata?: { readonly [x: string]: JsonValue } | null
+        readonly time: { readonly created: number }
+        readonly sessionID: string
+        readonly text: string
+        readonly type: "synthetic"
+      }
+    | {
+        readonly id: string
+        readonly metadata?: { readonly [x: string]: JsonValue } | null
+        readonly time: { readonly created: number }
+        readonly type: "system"
+        readonly text: string
+      }
+    | {
+        readonly id: string
+        readonly metadata?: { readonly [x: string]: JsonValue } | null
+        readonly time: { readonly created: number; readonly completed?: number | null }
+        readonly type: "shell"
+        readonly callID: string
+        readonly command: string
+        readonly output: string
+      }
+    | {
+        readonly id: string
+        readonly metadata?: { readonly [x: string]: JsonValue } | null
+        readonly time: { readonly created: number; readonly completed?: number | null }
+        readonly type: "assistant"
+        readonly agent: string
+        readonly model: { readonly id: string; readonly providerID: string; readonly variant?: string | null }
+        readonly content: ReadonlyArray<
+          | { readonly type: "text"; readonly id: string; readonly text: string }
+          | {
+              readonly type: "reasoning"
+              readonly id: string
+              readonly text: string
+              readonly providerMetadata?: { readonly [x: string]: { readonly [x: string]: JsonValue } } | null
+            }
+          | {
+              readonly type: "tool"
+              readonly id: string
+              readonly name: string
+              readonly provider?: {
+                readonly executed: boolean
+                readonly metadata?: { readonly [x: string]: { readonly [x: string]: JsonValue } } | null
+                readonly resultMetadata?: { readonly [x: string]: { readonly [x: string]: JsonValue } } | null
+              } | null
+              readonly state:
+                | { readonly status: "pending"; readonly input: string }
+                | {
+                    readonly status: "running"
+                    readonly input: { readonly [x: string]: JsonValue }
+                    readonly structured: { readonly [x: string]: any }
+                    readonly content: ReadonlyArray<
+                      | { readonly type: "text"; readonly text: string }
+                      | {
+                          readonly type: "file"
+                          readonly uri: string
+                          readonly mime: string
+                          readonly name?: string | null
+                        }
+                    >
+                  }
+                | {
+                    readonly status: "completed"
+                    readonly input: { readonly [x: string]: JsonValue }
+                    readonly attachments?: ReadonlyArray<{
+                      readonly uri: string
+                      readonly mime: string
+                      readonly name?: string | null
+                      readonly description?: string | null
+                      readonly source?: { readonly start: number; readonly end: number; readonly text: string } | null
+                    }> | null
+                    readonly content: ReadonlyArray<
+                      | { readonly type: "text"; readonly text: string }
+                      | {
+                          readonly type: "file"
+                          readonly uri: string
+                          readonly mime: string
+                          readonly name?: string | null
+                        }
+                    >
+                    readonly outputPaths?: ReadonlyArray<string> | null
+                    readonly structured: { readonly [x: string]: any }
+                    readonly result?: JsonValue | null
+                  }
+                | {
+                    readonly status: "error"
+                    readonly input: { readonly [x: string]: JsonValue }
+                    readonly content: ReadonlyArray<
+                      | { readonly type: "text"; readonly text: string }
+                      | {
+                          readonly type: "file"
+                          readonly uri: string
+                          readonly mime: string
+                          readonly name?: string | null
+                        }
+                    >
+                    readonly structured: { readonly [x: string]: any }
+                    readonly error: { readonly type: "unknown"; readonly message: string }
+                    readonly result?: JsonValue | null
+                  }
+              readonly time: {
+                readonly created: number
+                readonly ran?: number | null
+                readonly completed?: number | null
+                readonly pruned?: number | null
+              }
+            }
+        >
+        readonly snapshot?: { readonly start?: string | null; readonly end?: string | null } | null
+        readonly finish?: string | null
+        readonly cost?: number | null
+        readonly tokens?: {
+          readonly input: number
+          readonly output: number
+          readonly reasoning: number
+          readonly cache: { readonly read: number; readonly write: number }
+        } | null
+        readonly error?: { readonly type: "unknown"; readonly message: string } | null
+      }
+    | {
+        readonly type: "compaction"
+        readonly reason: "auto" | "manual"
+        readonly summary: string
+        readonly recent: string
+        readonly id: string
+        readonly metadata?: { readonly [x: string]: JsonValue } | null
+        readonly time: { readonly created: number }
+      }
+  >
+}["data"]

packages/client/src/index.ts

@@ -0,0 +1 @@
+export * from "./generated/index"

packages/client/test/contract-identity.test.ts

@@ -0,0 +1,50 @@
+import { expect, test } from "bun:test"
+import { Schema } from "effect"
+import { AgentV2 } from "@opencode-ai/core/agent"
+import { Location as CoreLocation } from "@opencode-ai/core/location"
+import { ModelV2 } from "@opencode-ai/core/model"
+import { SessionV2 } from "@opencode-ai/core/session"
+import { SessionInput as CoreSessionInput } from "@opencode-ai/core/session/input"
+import { SessionMessage as CoreSessionMessage } from "@opencode-ai/core/session/message"
+import { Prompt as CorePrompt } from "@opencode-ai/core/session/prompt"
+import { Agent } from "@opencode-ai/schema/agent"
+import { Location } from "@opencode-ai/schema/location"
+import { Model } from "@opencode-ai/schema/model"
+import { Project } from "@opencode-ai/schema/project"
+import { Provider } from "@opencode-ai/schema/provider"
+import { Prompt } from "@opencode-ai/schema/prompt"
+import { Session } from "@opencode-ai/schema/session"
+import { SessionInput } from "@opencode-ai/schema/session-input"
+import { SessionMessage } from "@opencode-ai/schema/session-message"
+import { Workspace } from "@opencode-ai/schema/workspace"
+import { SessionGroup } from "@opencode-ai/protocol/session"
+import { SessionGroup as ServerSessionGroup } from "@opencode-ai/server/groups/session"
+
+test("Core and Server reuse the authoritative Schema and Protocol values", () => {
+  expect(AgentV2.ID).toBe(Agent.ID)
+  expect(CoreLocation.Ref).toBe(Location.Ref)
+  expect(ModelV2.Ref).toBe(Model.Ref)
+  expect(SessionV2.Info).toBe(Session.Info)
+  expect(CoreSessionInput.Admitted).toBe(SessionInput.Admitted)
+  expect(CoreSessionMessage.Message).toBe(SessionMessage.Message)
+  expect(CorePrompt).toBe(Prompt)
+  expect(ServerSessionGroup).toBe(SessionGroup)
+  expect(Session.ID.create()).toStartWith("ses_")
+  expect(Session.ID.fromExternal({ namespace: "opencord.agent-thread", key: "thread-1" })).toMatch(/^ses_[a-f0-9]{64}$/)
+  expect(Project.ID.global).toBe("global")
+  expect(Provider.ID.anthropic).toBe("anthropic")
+  expect(Workspace.ID.create()).toStartWith("wrk_")
+})
+
+test("shared DTO schemas construct and decode plain objects", () => {
+  const made = Prompt.make({ text: "hello" })
+  const decoded = Schema.decodeUnknownSync(Prompt)({ text: "hello" })
+  const content = Schema.decodeUnknownSync(SessionMessage.AssistantText)({ type: "text", id: "part_1", text: "hi" })
+
+  expect(Object.getPrototypeOf(made)).toBe(Object.prototype)
+  expect(Object.getPrototypeOf(decoded)).toBe(Object.prototype)
+  expect(Object.getPrototypeOf(content)).toBe(Object.prototype)
+  expect(Prompt.ast.annotations?.identifier).toBe("Prompt")
+  expect(SessionMessage.AssistantText.ast.annotations?.identifier).toBe("Session.Message.Assistant.Text")
+  expect(CoreSessionMessage.AssistantText).toBe(SessionMessage.AssistantText)
+})

packages/client/test/effect.test.ts

@@ -0,0 +1,98 @@
+import { expect, test } from "bun:test"
+import { DateTime, Effect } from "effect"
+import { HttpClient, HttpClientResponse } from "effect/unstable/http"
+import { AbsolutePath, Agent, Location, Model, OpenCode, Prompt, Session } from "../src/effect"
+
+test("sessions.get returns the decoded Effect projection", async () => {
+  const httpClient = HttpClient.make((request) =>
+    Effect.succeed(HttpClientResponse.fromWeb(request, Response.json(session))),
+  )
+  const result = await Effect.gen(function* () {
+    const client = yield* OpenCode.make({ baseUrl: "http://localhost:3000" })
+    return yield* client.sessions.get({ sessionID: Session.ID.make("ses_test") })
+  }).pipe(Effect.provideService(HttpClient.HttpClient, httpClient), Effect.runPromise)
+
+  expect(DateTime.toEpochMillis(result.time.created)).toBe(1_717_171_717_000)
+})
+
+test("session methods retain decoded Effect inputs and outputs", async () => {
+  const httpClient = HttpClient.make((request) => {
+    const url = request.url
+    if (url.includes("/prompt")) {
+      return Effect.succeed(HttpClientResponse.fromWeb(request, Response.json(admission)))
+    }
+    if (url.includes("/context")) {
+      return Effect.succeed(HttpClientResponse.fromWeb(request, Response.json({ data: [] })))
+    }
+    if (request.method === "POST" && url.endsWith("/api/session")) {
+      return Effect.succeed(HttpClientResponse.fromWeb(request, Response.json(session)))
+    }
+    if (request.method === "POST") {
+      return Effect.succeed(HttpClientResponse.fromWeb(request, new Response(null, { status: 204 })))
+    }
+    return Effect.succeed(
+      HttpClientResponse.fromWeb(request, Response.json({ data: [session.data], cursor: { next: "next" } })),
+    )
+  })
+  const result = await Effect.gen(function* () {
+    const client = yield* OpenCode.make({ baseUrl: "http://localhost:3000" })
+    const page = yield* client.sessions.list({ limit: 10 })
+    const created = yield* client.sessions.create({
+      location: Location.Ref.make({ directory: AbsolutePath.make("/tmp/project") }),
+    })
+    yield* client.sessions.switchAgent({ sessionID: Session.ID.make("ses_test"), agent: Agent.ID.make("build") })
+    yield* client.sessions.switchModel({
+      sessionID: Session.ID.make("ses_test"),
+      model: Model.Ref.make({ id: "claude", providerID: "anthropic" }),
+    })
+    const admitted = yield* client.sessions.prompt({
+      sessionID: Session.ID.make("ses_test"),
+      prompt: Prompt.make({ text: "Hello" }),
+      resume: false,
+    })
+    yield* client.sessions.compact({ sessionID: Session.ID.make("ses_test") })
+    yield* client.sessions.wait({ sessionID: Session.ID.make("ses_test") })
+    const context = yield* client.sessions.context({ sessionID: Session.ID.make("ses_test") })
+    return { page, created, admitted, context }
+  }).pipe(Effect.provideService(HttpClient.HttpClient, httpClient), Effect.runPromise)
+
+  expect(DateTime.toEpochMillis(result.page.data[0].time.created)).toBe(1_717_171_717_000)
+  expect(Object.getPrototypeOf(result.page.data[0])).toBe(Object.prototype)
+  expect(Object.getPrototypeOf(result.created)).toBe(Object.prototype)
+  expect(result.created.id).toBe("ses_test")
+  expect(Object.getPrototypeOf(result.admitted)).toBe(Object.prototype)
+  expect(Object.getPrototypeOf(result.admitted.prompt)).toBe(Object.prototype)
+  expect(DateTime.toEpochMillis(result.admitted.timeCreated)).toBe(1_717_171_717_000)
+  expect(result.context).toEqual([])
+})
+
+const session = {
+  data: {
+    id: "ses_test",
+    projectID: "project",
+    cost: 0,
+    tokens: {
+      input: 1,
+      output: 2,
+      reasoning: 3,
+      cache: { read: 4, write: 5 },
+    },
+    time: {
+      created: 1_717_171_717_000,
+      updated: 1_717_171_717_000,
+    },
+    title: "Test",
+    location: { directory: "/tmp/project" },
+  },
+}
+
+const admission = {
+  data: {
+    admittedSeq: 0,
+    id: "msg_test",
+    sessionID: "ses_test",
+    prompt: { text: "Hello" },
+    delivery: "steer",
+    timeCreated: 1_717_171_717_000,
+  },
+}

packages/client/test/import-boundaries.test.ts

@@ -0,0 +1,68 @@
+import { describe, expect, test } from "bun:test"
+import { realpathSync } from "node:fs"
+import { mkdtemp, rm } from "node:fs/promises"
+import { join, resolve, sep } from "node:path"
+
+const directory = resolve(import.meta.dir, "..")
+const effect = realpathSync(resolve(import.meta.dir, "../node_modules/effect"))
+const schema = resolve(import.meta.dir, "../../schema")
+const protocol = resolve(import.meta.dir, "../../protocol")
+const core = resolve(import.meta.dir, "../../core")
+const server = resolve(import.meta.dir, "../../server")
+
+describe("public import boundaries", () => {
+  test("isolates each public entrypoint", async () => {
+    const root = await bundleInputs("@opencode-ai/client", "browser")
+
+    expect(within(root, effect)).toEqual([])
+    expect(within(root, schema)).toEqual([])
+    expect(within(root, protocol)).toEqual([])
+    expect(within(root, core)).toEqual([])
+    expect(within(root, server)).toEqual([])
+
+    const network = await bundleInputs("@opencode-ai/client/effect", "browser")
+
+    expect(within(network, effect).length).toBeGreaterThan(0)
+    expect(within(network, schema).length).toBeGreaterThan(0)
+    expect(within(network, protocol).length).toBeGreaterThan(0)
+    expect(within(network, core)).toEqual([])
+    expect(within(network, server)).toEqual([])
+  })
+})
+
+async function bundleInputs(specifier: string, target: "browser" | "bun") {
+  const temporary = await mkdtemp(join(import.meta.dir, ".import-boundary-"))
+  const entrypoint = join(temporary, "index.ts")
+  const metafile = join(temporary, "meta.json")
+  try {
+    await Bun.write(entrypoint, `export * from ${JSON.stringify(specifier)}`)
+    const child = Bun.spawn(
+      [
+        process.execPath,
+        "build",
+        entrypoint,
+        `--target=${target}`,
+        "--format=esm",
+        "--packages=bundle",
+        `--metafile=${metafile}`,
+        `--outdir=${join(temporary, "out")}`,
+      ],
+      { cwd: directory, stdout: "pipe", stderr: "pipe" },
+    )
+    const [exitCode, stdout, stderr] = await Promise.all([
+      child.exited,
+      new Response(child.stdout).text(),
+      new Response(child.stderr).text(),
+    ])
+    if (exitCode !== 0) throw new Error(stdout + stderr)
+    const metadata = await Bun.file(metafile).json()
+    return Object.keys(metadata.inputs).map((input) => resolve(directory, input))
+  } finally {
+    await rm(temporary, { recursive: true, force: true })
+  }
+}
+
+function within(inputs: ReadonlyArray<string>, directory: string) {
+  const prefix = directory.endsWith(sep) ? directory : directory + sep
+  return inputs.filter((input) => input === directory || input.startsWith(prefix))
+}

packages/client/test/promise.test.ts

@@ -0,0 +1,117 @@
+import { expect, test } from "bun:test"
+import { isUnauthorizedError, OpenCode } from "../src"
+
+test("sessions.get returns the wire projection", async () => {
+  const client = OpenCode.make({
+    baseUrl: "http://localhost:3000",
+    fetch: async (input) => {
+      expect(typeof input === "string" ? input : input instanceof URL ? input.href : input.url).toBe(
+        "http://localhost:3000/api/session/ses_test",
+      )
+      return Response.json(session)
+    },
+  })
+
+  const result = await client.sessions.get({ sessionID: "ses_test" })
+
+  expect(result.time.created).toBe(1_717_171_717_000)
+})
+
+test("session methods use the public HTTP contract", async () => {
+  const requests: Array<{ url: string; init?: RequestInit }> = []
+  const client = OpenCode.make({
+    baseUrl: "http://localhost:3000",
+    fetch: async (input, init) => {
+      const url = typeof input === "string" ? input : input instanceof URL ? input.href : input.url
+      requests.push({ url, init })
+      if (url.includes("/prompt")) return Response.json(admission)
+      if (url.includes("/context")) return Response.json({ data: [] })
+      if (init?.method === "POST" && url.endsWith("/api/session")) return Response.json(session)
+      if (init?.method === "POST") return new Response(null, { status: 204 })
+      return Response.json({ data: [session.data], cursor: { next: "next" } })
+    },
+  })
+
+  const page = await client.sessions.list({ limit: "10", order: "desc" })
+  const created = await client.sessions.create({ location: { directory: "/tmp/project" } })
+  await client.sessions.switchAgent({ sessionID: "ses_test", agent: "build" })
+  await client.sessions.switchModel({
+    sessionID: "ses_test",
+    model: { id: "claude", providerID: "anthropic" },
+  })
+  const admitted = await client.sessions.prompt({
+    sessionID: "ses_test",
+    prompt: { text: "Hello" },
+    resume: false,
+  })
+  await client.sessions.compact({ sessionID: "ses_test" })
+  await client.sessions.wait({ sessionID: "ses_test" })
+  const context = await client.sessions.context({ sessionID: "ses_test" })
+
+  expect(page.cursor.next).toBe("next")
+  expect(created.id).toBe("ses_test")
+  expect(admitted.id).toBe("msg_test")
+  expect(context).toEqual([])
+  expect(requests.map((request) => [request.init?.method, request.url])).toEqual([
+    ["GET", "http://localhost:3000/api/session?limit=10&order=desc"],
+    ["POST", "http://localhost:3000/api/session"],
+    ["POST", "http://localhost:3000/api/session/ses_test/agent"],
+    ["POST", "http://localhost:3000/api/session/ses_test/model"],
+    ["POST", "http://localhost:3000/api/session/ses_test/prompt"],
+    ["POST", "http://localhost:3000/api/session/ses_test/compact"],
+    ["POST", "http://localhost:3000/api/session/ses_test/wait"],
+    ["GET", "http://localhost:3000/api/session/ses_test/context"],
+  ])
+  const body = requests[4]?.init?.body
+  if (typeof body !== "string") throw new Error("Expected JSON request body")
+  expect(JSON.parse(body)).toEqual({
+    prompt: { text: "Hello" },
+    resume: false,
+  })
+})
+
+test("middleware errors remain declared client errors", async () => {
+  const client = OpenCode.make({
+    baseUrl: "http://localhost:3000",
+    fetch: async () =>
+      Response.json({ _tag: "UnauthorizedError", message: "Authentication required" }, { status: 401 }),
+  })
+
+  try {
+    await client.sessions.create({})
+    throw new Error("Expected request to fail")
+  } catch (error) {
+    expect(isUnauthorizedError(error)).toBe(true)
+  }
+})
+
+const session = {
+  data: {
+    id: "ses_test",
+    projectID: "project",
+    cost: 0,
+    tokens: {
+      input: 1,
+      output: 2,
+      reasoning: 3,
+      cache: { read: 4, write: 5 },
+    },
+    time: {
+      created: 1_717_171_717_000,
+      updated: 1_717_171_717_000,
+    },
+    title: "Test",
+    location: { directory: "/tmp/project" },
+  },
+}
+
+const admission = {
+  data: {
+    admittedSeq: 0,
+    id: "msg_test",
+    sessionID: "ses_test",
+    prompt: { text: "Hello" },
+    delivery: "steer",
+    timeCreated: 1_717_171_717_000,
+  },
+}

packages/client/tsconfig.json

@@ -0,0 +1,9 @@
+{
+  "$schema": "https://json.schemastore.org/tsconfig",
+  "extends": "@tsconfig/bun/tsconfig.json",
+  "compilerOptions": {
+    "lib": ["ESNext", "DOM", "DOM.Iterable"],
+    "noUncheckedIndexedAccess": false
+  },
+  "include": ["src"]
+}

packages/core/package.json

@@ -91,6 +91,7 @@
     "@opencode-ai/effect-drizzle-sqlite": "workspace:*",
     "@opencode-ai/effect-sqlite-node": "workspace:*",
     "@opencode-ai/llm": "workspace:*",
+    "@opencode-ai/schema": "workspace:*",
     "@opencode-ai/plugin": "workspace:*",
     "@opentelemetry/api": "1.9.0",
     "@opentelemetry/context-async-hooks": "2.6.1",

packages/core/src/agent.ts

@@ -1,13 +1,14 @@
 export * as AgentV2 from "./agent"
 
-import { Array, Context, Effect, Layer, Schema, Scope, Types } from "effect"
+import { Array, Context, Effect, Layer, Schema, Types } from "effect"
+import { Agent } from "@opencode-ai/schema/agent"
 import { ModelV2 } from "./model"
 import { PermissionSchema } from "./permission/schema"
 import { ProviderV2 } from "./provider"
 import { PositiveInt } from "./schema"
 import { State } from "./state"
 
-export const ID = Schema.String.pipe(Schema.brand("AgentV2.ID"))
+export const ID = Agent.ID
 export type ID = typeof ID.Type
 export const defaultID = ID.make("build")
 

packages/core/src/location-layer.ts

@@ -1,4 +1,4 @@
-import { Effect, Layer, LayerMap } from "effect"
+import { Context, Data, Effect, Layer, LayerMap, Scope } from "effect"
 import { Location } from "./location"
 import { Policy } from "./policy"
 import { Config } from "./config"
@@ -48,12 +48,48 @@ import { SessionRunnerModel } from "./session/runner/model"
 import { SystemContextBuiltIns } from "./system-context/builtins"
 import { FetchHttpClient } from "effect/unstable/http"
 
-export class LocationServiceMap extends LayerMap.Service<LocationServiceMap>()("@opencode/example/LocationServiceMap", {
-  lookup: (ref: Location.Ref) => {
+class LocationRefKey extends Data.Class<{
+  readonly directory: Location.Ref["directory"]
+  readonly workspaceID: Location.Ref["workspaceID"] | null
+}> {}
+
+const locationRefKey = (ref: Location.Ref) =>
+  new LocationRefKey({ directory: ref.directory, workspaceID: ref.workspaceID ?? null })
+
+const locationServiceDependencies = [
+  Project.defaultLayer,
+  EventV2.defaultLayer,
+  Credential.defaultLayer,
+  Npm.defaultLayer,
+  ModelsDev.defaultLayer,
+  FSUtil.defaultLayer,
+  Git.defaultLayer,
+  AppProcess.defaultLayer,
+  Global.defaultLayer,
+  Ripgrep.defaultLayer,
+  Database.defaultLayer,
+  ProjectDirectories.defaultLayer,
+  SessionStore.layer.pipe(Layer.provide(Database.defaultLayer)),
+  PermissionSaved.defaultLayer,
+  RepositoryCache.defaultLayer,
+  LLMClient.layer.pipe(Layer.provide(RequestExecutor.defaultLayer)),
+  FetchHttpClient.layer,
+  ToolOutputStore.defaultCleanupLayer,
+] as const
+
+class LocationServiceCache extends LayerMap.Service<LocationServiceCache>()("@opencode/example/LocationServiceCache", {
+  lookup: (ref: ReturnType<typeof locationRefKey>) => {
+    const locationRef = Location.Ref.make({
+      directory: ref.directory,
+      ...(ref.workspaceID === null ? {} : { workspaceID: ref.workspaceID }),
+    })
     const boot = Layer.effectDiscard(
-      Effect.logInfo("booting location services", { directory: ref.directory, workspaceID: ref.workspaceID }),
+      Effect.logInfo("booting location services", {
+        directory: locationRef.directory,
+        workspaceID: locationRef.workspaceID,
+      }),
     )
-    const location = Location.layer(ref)
+    const location = Location.layer(locationRef)
     const systemContext = SystemContextBuiltIns.locationLayer
     const base = Layer.mergeAll(
       location,
@@ -123,25 +159,45 @@ export class LocationServiceMap extends LayerMap.Service<LocationServiceMap>()("
     ).pipe(Layer.fresh)
   },
   idleTimeToLive: "60 minutes",
-  dependencies: [
-    Project.defaultLayer,
-    EventV2.defaultLayer,
-    Credential.defaultLayer,
-    Npm.defaultLayer,
-    ModelsDev.defaultLayer,
-    FSUtil.defaultLayer,
-    Git.defaultLayer,
-    AppProcess.defaultLayer,
-    Global.defaultLayer,
-    Ripgrep.defaultLayer,
-    Database.defaultLayer,
-    ProjectDirectories.defaultLayer,
-    SessionStore.layer.pipe(Layer.provide(Database.defaultLayer)),
-    PermissionSaved.defaultLayer,
-    RepositoryCache.defaultLayer,
-    LLMClient.layer.pipe(Layer.provide(RequestExecutor.defaultLayer)),
-    FetchHttpClient.layer,
-    ToolOutputStore.defaultCleanupLayer,
-    ApplicationTools.layer,
-  ],
+  dependencies: [...locationServiceDependencies, ApplicationTools.layer],
 }) {}
+
+type LocationServices = Layer.Success<ReturnType<typeof LocationServiceCache.get>>
+
+export interface LocationServiceMapService {
+  readonly get: (ref: Location.Ref) => Layer.Layer<LocationServices>
+  readonly contextEffect: (ref: Location.Ref) => Effect.Effect<Context.Context<LocationServices>, never, Scope.Scope>
+  readonly invalidate: (ref: Location.Ref) => Effect.Effect<void>
+}
+
+const locationServiceMapLayer = <E, R>(
+  service: Context.Service<LocationServiceMap, LocationServiceMapService>,
+  cache: Layer.Layer<LocationServiceCache, E, R>,
+) =>
+  Layer.effect(
+    service,
+    Effect.map(LocationServiceCache, (locations) =>
+      service.of({
+        get: (ref) => locations.get(locationRefKey(ref)),
+        contextEffect: (ref) => locations.contextEffect(locationRefKey(ref)),
+        invalidate: (ref) => locations.invalidate(locationRefKey(ref)),
+      }),
+    ),
+  ).pipe(Layer.provide(cache))
+
+export class LocationServiceMap extends Context.Service<LocationServiceMap, LocationServiceMapService>()(
+  "@opencode/example/LocationServiceMap",
+) {
+  static readonly get = (ref: Location.Ref) =>
+    Layer.unwrap(Effect.map(LocationServiceMap, (locations) => locations.get(ref)))
+  static readonly contextEffect = (ref: Location.Ref) =>
+    Effect.flatMap(LocationServiceMap, (locations) => locations.contextEffect(ref))
+  static readonly invalidate = (ref: Location.Ref) =>
+    Effect.flatMap(LocationServiceMap, (locations) => locations.invalidate(ref))
+  static readonly layer: Layer.Layer<LocationServiceMap> = locationServiceMapLayer(this, LocationServiceCache.layer)
+  static readonly layerWithApplicationTools: Layer.Layer<LocationServiceMap, never, ApplicationTools.Service> =
+    locationServiceMapLayer(
+      this,
+      LocationServiceCache.layerNoDeps.pipe(Layer.provide(Layer.mergeAll(...locationServiceDependencies))),
+    )
+}

packages/core/src/location.ts

@@ -1,14 +1,13 @@
 import { Context, Effect, Layer, Schema } from "effect"
+import { Location as SchemaLocation } from "@opencode-ai/schema/location"
 import { Project } from "./project"
 import { AbsolutePath, optionalOmitUndefined } from "./schema"
 import { WorkspaceV2 } from "./workspace"
 
 export * as Location from "./location"
 
-export class Ref extends Schema.Class<Ref>("Location.Ref")({
-  directory: AbsolutePath,
-  workspaceID: Schema.optional(WorkspaceV2.ID).pipe(Schema.withConstructorDefault(Effect.succeed(undefined))),
-}) {}
+export const Ref = SchemaLocation.Ref
+export type Ref = SchemaLocation.Ref
 
 export class Info extends Schema.Class<Info>("Location.Info")({
   directory: AbsolutePath,

packages/core/src/model.ts

@@ -1,11 +1,12 @@
 import { Schema, Types } from "effect"
+import { Model } from "@opencode-ai/schema/model"
 import { ProviderV2 } from "./provider"
 import { ModelRequest } from "./model-request"
 
-export const ID = Schema.String.pipe(Schema.brand("ModelV2.ID"))
+export const ID = Model.ID
 export type ID = typeof ID.Type
 
-export const VariantID = Schema.String.pipe(Schema.brand("VariantID"))
+export const VariantID = Model.VariantID
 export type VariantID = typeof VariantID.Type
 
 // Grouping of models, eg claude opus, claude sonnet
@@ -33,11 +34,7 @@ export const Cost = Schema.Struct({
   }),
 })
 
-export const Ref = Schema.Struct({
-  id: ID,
-  providerID: ProviderV2.ID,
-  variant: VariantID.pipe(Schema.optional),
-})
+export const Ref = Model.Ref
 export type Ref = typeof Ref.Type
 
 export const Api = Schema.Union([

packages/core/src/project/schema.ts

@@ -1,14 +1,10 @@
 export * as ProjectSchema from "./schema"
 
 import { Schema } from "effect"
-import { AbsolutePath, withStatics } from "../schema"
+import { Project } from "@opencode-ai/schema/project"
+import { AbsolutePath } from "../schema"
 
-export const ID = Schema.String.pipe(
-  Schema.brand("Project.ID"),
-  withStatics((schema) => ({
-    global: schema.make("global"),
-  })),
-)
+export const ID = Project.ID
 export type ID = typeof ID.Type
 
 export const Vcs = Schema.Union([

packages/core/src/provider.ts

@@ -1,25 +1,9 @@
 export * as ProviderV2 from "./provider"
 
-import { withStatics } from "./schema"
 import { Schema, Types } from "effect"
+import { Provider } from "@opencode-ai/schema/provider"
 
-export const ID = Schema.String.pipe(
-  Schema.brand("ProviderV2.ID"),
-  withStatics((schema) => ({
-    // Well-known providers
-    opencode: schema.make("opencode"),
-    anthropic: schema.make("anthropic"),
-    openai: schema.make("openai"),
-    google: schema.make("google"),
-    googleVertex: schema.make("google-vertex"),
-    githubCopilot: schema.make("github-copilot"),
-    amazonBedrock: schema.make("amazon-bedrock"),
-    azure: schema.make("azure"),
-    openrouter: schema.make("openrouter"),
-    mistral: schema.make("mistral"),
-    gitlab: schema.make("gitlab"),
-  })),
-)
+export const ID = Provider.ID
 export type ID = typeof ID.Type
 
 export const AISDK = Schema.Struct({

packages/core/src/public/opencode.ts

@@ -28,7 +28,7 @@ const SessionsLayer = SessionV2.layer.pipe(
   Layer.provide(EventV2.layer),
   Layer.provide(Database.defaultLayer),
   Layer.provide(ProjectV2.defaultLayer),
-  Layer.provide(LocationServiceMap.layer.pipe(Layer.provide(ApplicationTools.layer))),
+  Layer.provide(LocationServiceMap.layerWithApplicationTools.pipe(Layer.provide(ApplicationTools.layer))),
   Layer.orDie,
 )
 // TODO: Accept explicit storage so tests and embeddings can select disposable or application-owned persistence.

packages/core/src/schema.ts

@@ -1,47 +1,27 @@
-import { Option, Schema, SchemaGetter } from "effect"
-import { Hash } from "./util/hash"
+import { Schema } from "effect"
+import {
+  AbsolutePath,
+  DateTimeUtcFromMillis,
+  externalID,
+  type ExternalID,
+  NonNegativeInt,
+  optionalOmitUndefined,
+  PositiveInt,
+  RelativePath,
+  withStatics,
+} from "@opencode-ai/schema/schema"
 
-export type ExternalID = {
-  readonly namespace: string
-  readonly key: string
+export {
+  AbsolutePath,
+  DateTimeUtcFromMillis,
+  externalID,
+  NonNegativeInt,
+  optionalOmitUndefined,
+  PositiveInt,
+  RelativePath,
+  withStatics,
 }
-
-export const externalID = (prefix: string, input: ExternalID) =>
-  `${prefix}_${Hash.sha256(JSON.stringify([input.namespace, input.key]))}`
-
-/**
- * Integer greater than zero.
- */
-export const PositiveInt = Schema.Int.check(Schema.isGreaterThan(0))
-
-/**
- * Integer greater than or equal to zero.
- */
-export const NonNegativeInt = Schema.Int.check(Schema.isGreaterThanOrEqualTo(0))
-
-/**
- * Relative file path (e.g., `src/components/Button.tsx`).
- */
-export const RelativePath = Schema.String.pipe(Schema.brand("RelativePath"))
-export type RelativePath = Schema.Schema.Type<typeof RelativePath>
-
-/**
- * Absolute file path (e.g., `/home/user/projects/myapp/src/main.ts`).
- */
-export const AbsolutePath = Schema.String.pipe(Schema.brand("AbsolutePath"))
-export type AbsolutePath = Schema.Schema.Type<typeof AbsolutePath>
-
-/**
- * Optional public JSON field that can hold explicit `undefined` on the type
- * side but encodes it as an omitted key, matching legacy `JSON.stringify`.
- */
-export const optionalOmitUndefined = <S extends Schema.Top>(schema: S) =>
-  Schema.optionalKey(schema).pipe(
-    Schema.decodeTo(Schema.optional(schema), {
-      decode: SchemaGetter.passthrough({ strict: false }),
-      encode: SchemaGetter.transformOptional(Option.filter((value) => value !== undefined)),
-    }),
-  )
+export type { ExternalID }
 
 /**
  * Strip `readonly` from a nested type. Stand-in for `effect`'s `Types.DeepMutable`
@@ -71,22 +51,6 @@ export type DeepMutable<T> = T extends string | number | boolean | bigint | symb
         ? { -readonly [K in keyof T]: DeepMutable<T[K]> }
         : T
 
-/**
- * Attach static methods to a schema object. Designed to be used with `.pipe()`:
- *
- * @example
- *   export const Foo = fooSchema.pipe(
- *     withStatics((schema) => ({
- *       zero: schema.make(0),
- *       from: Schema.decodeUnknownOption(schema),
- *     }))
- *   )
- */
-export const withStatics =
-  <S extends object, M extends Record<string, unknown>>(methods: (schema: S) => M) =>
-  (schema: S): S & M =>
-    Object.assign(schema, methods(schema))
-
 /**
  * Nominal wrapper for scalar types. The class itself is a valid schema —
  * pass it directly to `Schema.decode`, `Schema.decodeEffect`, etc.

packages/core/src/session.ts

@@ -2,6 +2,7 @@ export * as SessionV2 from "./session"
 export * from "./session/schema"
 
 import { DateTime, Effect, Layer, Schema, Context, Stream } from "effect"
+import { Session as SchemaSession } from "@opencode-ai/schema/session"
 import { and, asc, desc, eq, gt, like, lt, or, type SQL } from "drizzle-orm"
 import { ProjectV2 } from "./project"
 import { WorkspaceV2 } from "./workspace"
@@ -38,11 +39,7 @@ import { SessionInput } from "./session/input"
 //   - by subpath
 // - by workspace (home is special)
 
-export const ListAnchor = Schema.Struct({
-  id: SessionSchema.ID,
-  time: Schema.Finite,
-  direction: Schema.Literals(["previous", "next"]),
-})
+export const ListAnchor = SchemaSession.ListAnchor
 export type ListAnchor = typeof ListAnchor.Type
 
 const ListInputBase = {

packages/core/src/session/event.ts

@@ -2,12 +2,10 @@ import { Schema } from "effect"
 import { ProviderMetadata, ToolContent } from "@opencode-ai/llm"
 import { EventV2 } from "../event"
 import { ModelV2 } from "../model"
-import { NonNegativeInt } from "../schema"
-import { V2Schema } from "../v2-schema"
+import { DateTimeUtcFromMillis, NonNegativeInt, RelativePath } from "../schema"
 import { FileAttachment, Prompt } from "./prompt"
 import { SessionSchema } from "./schema"
 import { Location } from "../location"
-import { RelativePath } from "../schema"
 import { SessionMessageID } from "./message-id"
 
 export { FileAttachment }
@@ -22,7 +20,7 @@ export const Source = Schema.Struct({
 export type Source = typeof Source.Type
 
 const Base = {
-  timestamp: V2Schema.DateTimeUtcFromMillis,
+  timestamp: DateTimeUtcFromMillis,
   sessionID: SessionSchema.ID,
 }
 const PromptFields = {

packages/core/src/session/input.ts

@@ -2,10 +2,9 @@ export * as SessionInput from "./input"
 
 import { and, asc, eq, isNull, lte } from "drizzle-orm"
 import { DateTime, Effect, Schema } from "effect"
+import { SessionInput as SchemaSessionInput } from "@opencode-ai/schema/session-input"
 import type { Database } from "../database/database"
 import type { EventV2 } from "../event"
-import { NonNegativeInt } from "../schema"
-import { V2Schema } from "../v2-schema"
 import { SessionEvent } from "./event"
 import { SessionMessage } from "./message"
 import { Prompt } from "./prompt"
@@ -14,24 +13,17 @@ import { SessionInputTable, SessionMessageTable } from "./sql"
 
 type DatabaseService = Database.Interface["db"]
 
-export const Delivery = Schema.Literals(["steer", "queue"])
+export const Delivery = SchemaSessionInput.Delivery
 export type Delivery = typeof Delivery.Type
 
-export class Admitted extends Schema.Class<Admitted>("SessionInput.Admitted")({
-  admittedSeq: NonNegativeInt,
-  id: SessionMessage.ID,
-  sessionID: SessionSchema.ID,
-  prompt: Prompt,
-  delivery: Delivery,
-  timeCreated: V2Schema.DateTimeUtcFromMillis,
-  promotedSeq: NonNegativeInt.pipe(Schema.optional),
-}) {}
+export const Admitted = SchemaSessionInput.Admitted
+export type Admitted = SchemaSessionInput.Admitted
 
 const decodePrompt = Schema.decodeUnknownSync(Prompt)
 const encodePrompt = Schema.encodeSync(Prompt)
 
 const fromRow = (row: typeof SessionInputTable.$inferSelect): Admitted =>
-  new Admitted({
+  Admitted.make({
     admittedSeq: row.admitted_seq,
     id: SessionMessage.ID.make(row.id),
     sessionID: SessionSchema.ID.make(row.session_id),
@@ -76,7 +68,7 @@ export const admit = Effect.fn("SessionInput.admit")(function* (
         event.durable === undefined
           ? Effect.die("Prompt admission event is missing aggregate sequence")
           : Effect.succeed(
-              new Admitted({
+              Admitted.make({
                 admittedSeq: event.durable.seq,
                 id: input.id,
                 sessionID: input.sessionID,

packages/core/src/session/message-id.ts

@@ -1,13 +1,2 @@
 export * as SessionMessageID from "./message-id"
-
-import { Schema } from "effect"
-import { withStatics } from "../schema"
-import { Identifier } from "../util/identifier"
-
-export const ID = Schema.String.check(Schema.isStartsWith("msg_")).pipe(
-  Schema.brand("Session.Message.ID"),
-  withStatics((schema) => ({
-    create: () => schema.make("msg_" + Identifier.ascending()),
-  })),
-)
-export type ID = typeof ID.Type
+export { ID } from "@opencode-ai/schema/session-message"

packages/core/src/session/message-updater.ts

@@ -102,7 +102,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
     yield* SessionEvent.All.match(event, {
       "session.next.agent.switched": (event) => {
         return adapter.appendMessage(
-          new SessionMessage.AgentSwitched({
+          SessionMessage.AgentSwitched.make({
             id: event.data.messageID,
             type: "agent-switched",
             metadata: event.metadata,
@@ -113,7 +113,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
       },
       "session.next.model.switched": (event) => {
         return adapter.appendMessage(
-          new SessionMessage.ModelSwitched({
+          SessionMessage.ModelSwitched.make({
             id: event.data.messageID,
             type: "model-switched",
             metadata: event.metadata,
@@ -125,7 +125,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
       "session.next.moved": () => Effect.void,
       "session.next.prompted": (event) => {
         return adapter.appendMessage(
-          new SessionMessage.User({
+          SessionMessage.User.make({
             id: event.data.messageID,
             type: "user",
             metadata: event.metadata,
@@ -139,7 +139,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
       "session.next.prompt.admitted": () => Effect.void,
       "session.next.context.updated": (event) =>
         adapter.appendMessage(
-          new SessionMessage.System({
+          SessionMessage.System.make({
             id: event.data.messageID,
             type: "system",
             text: event.data.text,
@@ -148,7 +148,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
         ),
       "session.next.synthetic": (event) => {
         return adapter.appendMessage(
-          new SessionMessage.Synthetic({
+          SessionMessage.Synthetic.make({
             sessionID: event.data.sessionID,
             text: event.data.text,
             id: event.data.messageID,
@@ -159,7 +159,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
       },
       "session.next.shell.started": (event) => {
         return adapter.appendMessage(
-          new SessionMessage.Shell({
+          SessionMessage.Shell.make({
             id: event.data.messageID,
             type: "shell",
             metadata: event.metadata,
@@ -194,7 +194,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
             )
           }
           yield* adapter.appendMessage(
-            new SessionMessage.Assistant({
+            SessionMessage.Assistant.make({
               id: event.data.assistantMessageID,
               type: "assistant",
               agent: event.data.agent,
@@ -225,7 +225,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
       "session.next.text.started": (event) => {
         return updateOwnedAssistant(event.data.assistantMessageID, (draft) => {
           draft.content.push(
-            castDraft(new SessionMessage.AssistantText({ type: "text", id: event.data.textID, text: "" })),
+            castDraft(SessionMessage.AssistantText.make({ type: "text", id: event.data.textID, text: "" })),
           )
         })
       },
@@ -245,12 +245,12 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
         return updateOwnedAssistant(event.data.assistantMessageID, (draft) => {
           draft.content.push(
             castDraft(
-              new SessionMessage.AssistantTool({
+              SessionMessage.AssistantTool.make({
                 type: "tool",
                 id: event.data.callID,
                 name: event.data.name,
                 time: { created: event.data.timestamp },
-                state: new SessionMessage.ToolStatePending({ status: "pending", input: "" }),
+                state: SessionMessage.ToolStatePending.make({ status: "pending", input: "" }),
               }),
             ),
           )
@@ -270,7 +270,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
             match.provider = event.data.provider
             match.time.ran = event.data.timestamp
             match.state = castDraft(
-              new SessionMessage.ToolStateRunning({
+              SessionMessage.ToolStateRunning.make({
                 status: "running",
                 input: event.data.input,
                 structured: {},
@@ -300,7 +300,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
             }
             match.time.completed = event.data.timestamp
             match.state = castDraft(
-              new SessionMessage.ToolStateCompleted({
+              SessionMessage.ToolStateCompleted.make({
                 status: "completed",
                 input: match.state.input,
                 structured: event.data.structured,
@@ -323,7 +323,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
             }
             match.time.completed = event.data.timestamp
             match.state = castDraft(
-              new SessionMessage.ToolStateError({
+              SessionMessage.ToolStateError.make({
                 status: "error",
                 error: event.data.error,
                 input: typeof match.state.input === "string" ? {} : match.state.input,
@@ -339,7 +339,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
         return updateOwnedAssistant(event.data.assistantMessageID, (draft) => {
           draft.content.push(
             castDraft(
-              new SessionMessage.AssistantReasoning({
+              SessionMessage.AssistantReasoning.make({
                 type: "reasoning",
                 id: event.data.reasoningID,
                 text: "",
@@ -369,7 +369,7 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
       "session.next.compaction.delta": () => Effect.void,
       "session.next.compaction.ended": (event) => {
         return adapter.appendMessage(
-          new SessionMessage.Compaction({
+          SessionMessage.Compaction.make({
             id: event.data.messageID,
             type: "compaction",
             metadata: event.metadata,

packages/core/src/session/message.ts

@@ -1,193 +1,2 @@
 export * as SessionMessage from "./message"
-
-import { Schema } from "effect"
-import { ProviderMetadata, ToolContent } from "@opencode-ai/llm"
-import { ModelV2 } from "../model"
-import { V2Schema } from "../v2-schema"
-import { SessionEvent } from "./event"
-import { Prompt } from "./prompt"
-import { SessionMessageID } from "./message-id"
-
-export const ID = SessionMessageID.ID
-export type ID = typeof ID.Type
-
-const Base = {
-  id: ID,
-  metadata: Schema.Record(Schema.String, Schema.Unknown).pipe(Schema.optional),
-  time: Schema.Struct({
-    created: V2Schema.DateTimeUtcFromMillis,
-  }),
-}
-
-export class AgentSwitched extends Schema.Class<AgentSwitched>("Session.Message.AgentSwitched")({
-  ...Base,
-  type: Schema.Literal("agent-switched"),
-  agent: SessionEvent.AgentSwitched.data.fields.agent,
-}) {}
-
-export class ModelSwitched extends Schema.Class<ModelSwitched>("Session.Message.ModelSwitched")({
-  ...Base,
-  type: Schema.Literal("model-switched"),
-  model: ModelV2.Ref,
-}) {}
-
-export class User extends Schema.Class<User>("Session.Message.User")({
-  ...Base,
-  text: Prompt.fields.text,
-  files: Prompt.fields.files,
-  agents: Prompt.fields.agents,
-  type: Schema.Literal("user"),
-  time: Schema.Struct({
-    created: V2Schema.DateTimeUtcFromMillis,
-  }),
-}) {}
-
-export class Synthetic extends Schema.Class<Synthetic>("Session.Message.Synthetic")({
-  ...Base,
-  sessionID: SessionEvent.Synthetic.data.fields.sessionID,
-  text: SessionEvent.Synthetic.data.fields.text,
-  type: Schema.Literal("synthetic"),
-}) {}
-
-export class System extends Schema.Class<System>("Session.Message.System")({
-  ...Base,
-  type: Schema.Literal("system"),
-  text: SessionEvent.ContextUpdated.data.fields.text,
-}) {}
-
-export class Shell extends Schema.Class<Shell>("Session.Message.Shell")({
-  ...Base,
-  type: Schema.Literal("shell"),
-  callID: SessionEvent.Shell.Started.data.fields.callID,
-  command: SessionEvent.Shell.Started.data.fields.command,
-  output: Schema.String,
-  time: Schema.Struct({
-    created: V2Schema.DateTimeUtcFromMillis,
-    completed: V2Schema.DateTimeUtcFromMillis.pipe(Schema.optional),
-  }),
-}) {}
-
-export class ToolStatePending extends Schema.Class<ToolStatePending>("Session.Message.ToolState.Pending")({
-  status: Schema.Literal("pending"),
-  input: Schema.String,
-}) {}
-
-export class ToolStateRunning extends Schema.Class<ToolStateRunning>("Session.Message.ToolState.Running")({
-  status: Schema.Literal("running"),
-  input: Schema.Record(Schema.String, Schema.Unknown),
-  structured: Schema.Record(Schema.String, Schema.Any),
-  content: ToolContent.pipe(Schema.Array),
-}) {}
-
-export class ToolStateCompleted extends Schema.Class<ToolStateCompleted>("Session.Message.ToolState.Completed")({
-  status: Schema.Literal("completed"),
-  input: Schema.Record(Schema.String, Schema.Unknown),
-  attachments: SessionEvent.FileAttachment.pipe(Schema.Array, Schema.optional),
-  content: ToolContent.pipe(Schema.Array),
-  outputPaths: SessionEvent.Tool.Success.data.fields.outputPaths,
-  structured: Schema.Record(Schema.String, Schema.Any),
-  result: SessionEvent.Tool.Success.data.fields.result,
-}) {}
-
-export class ToolStateError extends Schema.Class<ToolStateError>("Session.Message.ToolState.Error")({
-  status: Schema.Literal("error"),
-  input: Schema.Record(Schema.String, Schema.Unknown),
-  content: ToolContent.pipe(Schema.Array),
-  structured: Schema.Record(Schema.String, Schema.Any),
-  error: SessionEvent.UnknownError,
-  result: SessionEvent.Tool.Failed.data.fields.result,
-}) {}
-
-export const ToolState = Schema.Union([ToolStatePending, ToolStateRunning, ToolStateCompleted, ToolStateError]).pipe(
-  Schema.toTaggedUnion("status"),
-)
-export type ToolState = Schema.Schema.Type<typeof ToolState>
-
-export class AssistantTool extends Schema.Class<AssistantTool>("Session.Message.Assistant.Tool")({
-  type: Schema.Literal("tool"),
-  id: Schema.String,
-  name: Schema.String,
-  provider: Schema.Struct({
-    executed: Schema.Boolean,
-    metadata: ProviderMetadata.pipe(Schema.optional),
-    resultMetadata: ProviderMetadata.pipe(Schema.optional),
-  }).pipe(Schema.optional),
-  state: ToolState,
-  time: Schema.Struct({
-    created: V2Schema.DateTimeUtcFromMillis,
-    ran: V2Schema.DateTimeUtcFromMillis.pipe(Schema.optional),
-    completed: V2Schema.DateTimeUtcFromMillis.pipe(Schema.optional),
-    pruned: V2Schema.DateTimeUtcFromMillis.pipe(Schema.optional),
-  }),
-}) {}
-
-export class AssistantText extends Schema.Class<AssistantText>("Session.Message.Assistant.Text")({
-  type: Schema.Literal("text"),
-  id: Schema.String,
-  text: Schema.String,
-}) {}
-
-export class AssistantReasoning extends Schema.Class<AssistantReasoning>("Session.Message.Assistant.Reasoning")({
-  type: Schema.Literal("reasoning"),
-  id: Schema.String,
-  text: Schema.String,
-  providerMetadata: ProviderMetadata.pipe(Schema.optional),
-}) {}
-
-export const AssistantContent = Schema.Union([AssistantText, AssistantReasoning, AssistantTool]).pipe(
-  Schema.toTaggedUnion("type"),
-)
-export type AssistantContent = Schema.Schema.Type<typeof AssistantContent>
-
-export class Assistant extends Schema.Class<Assistant>("Session.Message.Assistant")({
-  ...Base,
-  type: Schema.Literal("assistant"),
-  agent: Schema.String,
-  model: SessionEvent.Step.Started.data.fields.model,
-  content: AssistantContent.pipe(Schema.Array),
-  snapshot: Schema.Struct({
-    start: Schema.String.pipe(Schema.optional),
-    end: Schema.String.pipe(Schema.optional),
-  }).pipe(Schema.optional),
-  finish: Schema.String.pipe(Schema.optional),
-  cost: Schema.Finite.pipe(Schema.optional),
-  tokens: Schema.Struct({
-    input: Schema.Finite,
-    output: Schema.Finite,
-    reasoning: Schema.Finite,
-    cache: Schema.Struct({
-      read: Schema.Finite,
-      write: Schema.Finite,
-    }),
-  }).pipe(Schema.optional),
-  error: SessionEvent.Step.Failed.data.fields.error.pipe(Schema.optional),
-  time: Schema.Struct({
-    created: V2Schema.DateTimeUtcFromMillis,
-    completed: V2Schema.DateTimeUtcFromMillis.pipe(Schema.optional),
-  }),
-}) {}
-
-export class Compaction extends Schema.Class<Compaction>("Session.Message.Compaction")({
-  type: Schema.Literal("compaction"),
-  reason: SessionEvent.Compaction.Started.data.fields.reason,
-  summary: Schema.String,
-  recent: Schema.String,
-  ...Base,
-}) {}
-
-export const Message = Schema.Union([
-  AgentSwitched,
-  ModelSwitched,
-  User,
-  Synthetic,
-  System,
-  Shell,
-  Assistant,
-  Compaction,
-])
-  .pipe(Schema.toTaggedUnion("type"))
-  .annotate({ identifier: "Session.Message" })
-
-export type Message = Schema.Schema.Type<typeof Message>
-
-export type Type = Message["type"]
+export * from "@opencode-ai/schema/session-message"

packages/core/src/session/prompt.ts

@@ -1,46 +1 @@
-import * as Schema from "effect/Schema"
-
-export class Source extends Schema.Class<Source>("Prompt.Source")({
-  start: Schema.Finite,
-  end: Schema.Finite,
-  text: Schema.String,
-}) {}
-
-export class FileAttachment extends Schema.Class<FileAttachment>("Prompt.FileAttachment")({
-  uri: Schema.String,
-  mime: Schema.String,
-  name: Schema.String.pipe(Schema.optional),
-  description: Schema.String.pipe(Schema.optional),
-  source: Source.pipe(Schema.optional),
-}) {
-  static create(input: FileAttachment) {
-    return new FileAttachment({
-      uri: input.uri,
-      mime: input.mime,
-      name: input.name,
-      description: input.description,
-      source: input.source,
-    })
-  }
-}
-
-export class AgentAttachment extends Schema.Class<AgentAttachment>("Prompt.AgentAttachment")({
-  name: Schema.String,
-  source: Source.pipe(Schema.optional),
-}) {}
-
-export class Prompt extends Schema.Class<Prompt>("Prompt")({
-  text: Schema.String,
-  files: Schema.Array(FileAttachment).pipe(Schema.optional),
-  agents: Schema.Array(AgentAttachment).pipe(Schema.optional),
-}) {
-  static readonly equivalence = Schema.toEquivalence(Prompt)
-
-  static fromUserMessage(input: Pick<Prompt, "text" | "files" | "agents">) {
-    return new Prompt({
-      text: input.text,
-      ...(input.files === undefined ? {} : { files: input.files }),
-      ...(input.agents === undefined ? {} : { agents: input.agents }),
-    })
-  }
-}
+export { AgentAttachment, FileAttachment, Prompt, Source } from "@opencode-ai/schema/prompt"

packages/core/src/session/schema.ts

@@ -1,49 +1,11 @@
 export * as SessionSchema from "./schema"
 
-import { Schema } from "effect"
-import { Location } from "../location"
-import { ModelV2 } from "../model"
-import { ProjectV2 } from "../project"
-import { externalID, type ExternalID, RelativePath, optionalOmitUndefined, withStatics } from "../schema"
-import { Identifier } from "../util/identifier"
-import { V2Schema } from "../v2-schema"
-import { AgentV2 } from "../agent"
+import { Session } from "@opencode-ai/schema/session"
+import type { ExternalID } from "../schema"
 
-export const ID = Schema.String.check(Schema.isStartsWith("ses")).pipe(
-  Schema.brand("SessionID"),
-  withStatics((schema) => {
-    const create = () => schema.make("ses_" + Identifier.descending())
-    return {
-      create,
-      descending: (id?: string) => (id === undefined ? create() : schema.make(id)),
-      fromExternal: (input: ExternalID) => schema.make(externalID("ses", input)),
-    }
-  }),
-)
+export const ID = Session.ID
 export type ID = typeof ID.Type
+export type { ExternalID }
 
-export class Info extends Schema.Class<Info>("SessionV2.Info")({
-  id: ID,
-  parentID: ID.pipe(optionalOmitUndefined),
-  projectID: ProjectV2.ID,
-  agent: AgentV2.ID.pipe(Schema.optional),
-  model: ModelV2.Ref.pipe(Schema.optional),
-  cost: Schema.Finite,
-  tokens: Schema.Struct({
-    input: Schema.Finite,
-    output: Schema.Finite,
-    reasoning: Schema.Finite,
-    cache: Schema.Struct({
-      read: Schema.Finite,
-      write: Schema.Finite,
-    }),
-  }),
-  time: Schema.Struct({
-    created: V2Schema.DateTimeUtcFromMillis,
-    updated: V2Schema.DateTimeUtcFromMillis,
-    archived: V2Schema.DateTimeUtcFromMillis.pipe(Schema.optional),
-  }),
-  title: Schema.String,
-  location: Location.Ref,
-  subpath: RelativePath.pipe(Schema.optional),
-}) {}
+export const Info = Session.Info
+export type Info = Session.Info

packages/core/src/v2-schema.ts

@@ -1,10 +0,0 @@
-import { DateTime, Schema, SchemaGetter } from "effect"
-
-export const DateTimeUtcFromMillis = Schema.Finite.pipe(
-  Schema.decodeTo(Schema.DateTimeUtc, {
-    decode: SchemaGetter.transform((value) => DateTime.makeUnsafe(value)),
-    encode: SchemaGetter.transform((value) => DateTime.toEpochMillis(value)),
-  }),
-)
-
-export * as V2Schema from "./v2-schema"

packages/core/src/workspace.ts

@@ -1,18 +1,6 @@
 export * as WorkspaceV2 from "./workspace"
 
-import { Schema } from "effect"
-import { withStatics } from "./schema"
-import { Identifier } from "./util/identifier"
+import { Workspace } from "@opencode-ai/schema/workspace"
 
-export const ID = Schema.String.check(Schema.isStartsWith("wrk")).pipe(
-  Schema.brand("WorkspaceV2.ID"),
-  withStatics((schema) => ({
-    ascending: (id?: string) => {
-      if (!id) return schema.make("wrk_" + Identifier.ascending())
-      if (!id.startsWith("wrk")) throw new Error(`ID ${id} does not start with wrk`)
-      return schema.make(id)
-    },
-    create: () => schema.make("wrk_" + Identifier.ascending()),
-  })),
-)
+export const ID = Workspace.ID
 export type ID = typeof ID.Type

packages/core/test/event.test.ts

@@ -4,9 +4,8 @@ import { EventV2 } from "@opencode-ai/core/event"
 import { Database } from "@opencode-ai/core/database/database"
 import { EventSequenceTable, EventTable } from "@opencode-ai/core/event/sql"
 import { Location } from "@opencode-ai/core/location"
-import { AbsolutePath } from "@opencode-ai/core/schema"
+import { AbsolutePath, DateTimeUtcFromMillis } from "@opencode-ai/core/schema"
 import { WorkspaceV2 } from "@opencode-ai/core/workspace"
-import { V2Schema } from "@opencode-ai/core/v2-schema"
 import { eq } from "drizzle-orm"
 import { location } from "./fixture/location"
 import { testEffect } from "./lib/effect"
@@ -79,7 +78,7 @@ const SyncTimestamp = EventV2.define({
   },
   schema: {
     id: Schema.String,
-    timestamp: V2Schema.DateTimeUtcFromMillis,
+    timestamp: DateTimeUtcFromMillis,
   },
 })
 

packages/core/test/location-layer.test.ts

@@ -1,7 +1,7 @@
 import fs from "fs/promises"
 import path from "path"
 import { describe, expect } from "bun:test"
-import { DateTime, Effect, Equal, Hash, Layer, Schema } from "effect"
+import { DateTime, Effect, Layer, Schema } from "effect"
 import { Tool } from "@opencode-ai/core/public"
 import { define } from "@opencode-ai/plugin/v2/effect"
 import { AgentV2 } from "@opencode-ai/core/agent"
@@ -34,7 +34,7 @@ const applicationTools = ApplicationTools.layer
 const it = testEffect(
   Layer.merge(
     Layer.mergeAll(applicationTools, Database.defaultLayer, EventV2.defaultLayer),
-    LocationServiceMap.layer.pipe(
+    LocationServiceMap.layerWithApplicationTools.pipe(
       Layer.provide(applicationTools),
       Layer.provide(
         Layer.mergeAll(
@@ -52,14 +52,24 @@ const it = testEffect(
 )
 
 describe("LocationServiceMap", () => {
-  it.effect("compares equivalent location refs by value", () =>
-    Effect.sync(() => {
-      const directory = AbsolutePath.make("/project")
-      expect(Equal.equals(Location.Ref.make({ directory }), Location.Ref.make({ directory }))).toBe(true)
-      expect(Hash.hash(Location.Ref.make({ directory }))).toBe(
-        Hash.hash(Location.Ref.make({ directory, workspaceID: undefined })),
-      )
-    }),
+  it.live("reuses cached services for equivalent location refs", () =>
+    Effect.acquireRelease(
+      Effect.promise(() => tmpdir()),
+      (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
+    ).pipe(
+      Effect.flatMap((dir) =>
+        Effect.scoped(
+          Effect.gen(function* () {
+            const locations = yield* LocationServiceMap
+            const directory = AbsolutePath.make(dir.path)
+            const first = yield* locations.contextEffect(Location.Ref.make({ directory }))
+            const second = yield* locations.contextEffect(Location.Ref.make({ directory, workspaceID: undefined }))
+
+            expect(first).toBe(second)
+          }),
+        ),
+      ),
+    ),
   )
 
   it.live("isolates location state while sharing location policy with catalog", () =>

packages/core/test/session-create.test.ts

@@ -218,7 +218,7 @@ describe("SessionV2.create", () => {
       const events = yield* EventV2.Service
       const { db } = yield* Database.Service
       const created = yield* session.create({ location })
-      yield* session.prompt({ sessionID: created.id, prompt: new Prompt({ text: "Hello" }), resume: false })
+      yield* session.prompt({ sessionID: created.id, prompt: Prompt.make({ text: "Hello" }), resume: false })
       yield* SessionInput.promoteSteers(db, events, created.id, Number.MAX_SAFE_INTEGER)
 
       expect(
@@ -238,7 +238,7 @@ describe("SessionV2.create", () => {
       const created = yield* session.create({ id: SessionV2.ID.make("ses_fresh_target_replay"), location })
       const admitted = yield* session.prompt({
         sessionID: created.id,
-        prompt: new Prompt({ text: "Replay lifecycle" }),
+        prompt: Prompt.make({ text: "Replay lifecycle" }),
         resume: false,
       })
       yield* SessionInput.promoteSteers(sourceDb, sourceEvents, created.id, Number.MAX_SAFE_INTEGER)

packages/core/test/session-projector.test.ts

@@ -36,7 +36,7 @@ const assistantRow = (
     id: _,
     type,
     ...data
-  } = encodeMessage(new SessionMessage.Assistant({ id, type: "assistant", agent: "build", model, content: [], time }))
+  } = encodeMessage(SessionMessage.Assistant.make({ id, type: "assistant", agent: "build", model, content: [], time }))
   return { id, session_id: sessionID, type, seq, time_created: DateTime.toEpochMillis(time.created), data }
 }
 
@@ -69,7 +69,7 @@ describe("SessionProjector", () => {
           sessionID,
           messageID: SessionMessage.ID.make("msg_first"),
           timestamp: created,
-          prompt: new Prompt({ text: "first" }),
+          prompt: Prompt.make({ text: "first" }),
           delivery: "steer",
         },
         { id: EventV2.ID.make("evt_z") },
@@ -80,7 +80,7 @@ describe("SessionProjector", () => {
           sessionID,
           messageID: SessionMessage.ID.make("msg_second"),
           timestamp: created,
-          prompt: new Prompt({ text: "second" }),
+          prompt: Prompt.make({ text: "second" }),
           delivery: "steer",
         },
         { id: EventV2.ID.make("evt_a") },
@@ -145,7 +145,7 @@ describe("SessionProjector", () => {
       const admitted = yield* SessionInput.admit(db, events, {
         id,
         sessionID,
-        prompt: new Prompt({ text: "promote me" }),
+        prompt: Prompt.make({ text: "promote me" }),
         delivery: "steer",
       })
       if (!admitted) return yield* Effect.die("Prompt admission failed")
@@ -154,7 +154,7 @@ describe("SessionProjector", () => {
         sessionID,
         timestamp: admitted.timeCreated,
         messageID: id,
-        prompt: new Prompt({ text: "promote me" }),
+        prompt: Prompt.make({ text: "promote me" }),
         delivery: "steer",
       })
 
@@ -334,7 +334,7 @@ describe("SessionProjector", () => {
 
   it.effect("does not revive a stale incomplete in-memory assistant projection", () =>
     Effect.gen(function* () {
-      const stale = new SessionMessage.Assistant({
+      const stale = SessionMessage.Assistant.make({
         id: SessionMessage.ID.make("msg_assistant_stale"),
         type: "assistant",
         agent: "build",
@@ -342,7 +342,7 @@ describe("SessionProjector", () => {
         content: [],
         time: { created },
       })
-      const completed = new SessionMessage.Assistant({
+      const completed = SessionMessage.Assistant.make({
         id: SessionMessage.ID.make("msg_assistant_completed"),
         type: "assistant",
         agent: "build",
@@ -466,15 +466,15 @@ describe("SessionProjector", () => {
         Schema.decodeUnknownSync(SessionMessage.Message)({ ...row.data, id: row.id, type: row.type }),
       )
       expect(messages).toEqual([
-        new SessionMessage.Assistant({
+        SessionMessage.Assistant.make({
           id: SessionMessage.ID.make("msg_assistant_completed"),
           type: "assistant",
           agent: "build",
           model,
-          content: [new SessionMessage.AssistantText({ type: "text", id: "text-stale", text: "" })],
+          content: [SessionMessage.AssistantText.make({ type: "text", id: "text-stale", text: "" })],
           time: { created: DateTime.makeUnsafe(1), completed: DateTime.makeUnsafe(2) },
         }),
-        new SessionMessage.Assistant({
+        SessionMessage.Assistant.make({
           id: SessionMessage.ID.make("msg_assistant_stale"),
           type: "assistant",
           agent: "build",

packages/core/test/session-prompt.test.ts

@@ -147,7 +147,7 @@ describe("SessionV2.prompt", () => {
 
       const message = yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Fix the failing tests" }),
+        prompt: Prompt.make({ text: "Fix the failing tests" }),
         resume: false,
       })
 
@@ -171,8 +171,8 @@ describe("SessionV2.prompt", () => {
       const fiber = yield* session.events({ sessionID }).pipe(Stream.take(4), Stream.runCollect, Effect.forkScoped)
       yield* Effect.yieldNow
 
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
       yield* SessionInput.promoteSteers(db, events, sessionID, Number.MAX_SAFE_INTEGER)
       const streamed = Array.from(yield* Fiber.join(fiber))
 
@@ -198,7 +198,7 @@ describe("SessionV2.prompt", () => {
       const session = yield* SessionV2.Service
       const message = yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Fix the failing tests" }),
+        prompt: Prompt.make({ text: "Fix the failing tests" }),
         resume: false,
       })
 
@@ -217,7 +217,7 @@ describe("SessionV2.prompt", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      const input = { sessionID, prompt: new Prompt({ text: "Fix the failing tests" }), resume: false }
+      const input = { sessionID, prompt: Prompt.make({ text: "Fix the failing tests" }), resume: false }
 
       const first = yield* session.prompt(input)
       const second = yield* session.prompt(input)
@@ -235,7 +235,7 @@ describe("SessionV2.prompt", () => {
       const input = {
         sessionID,
         id: messageID,
-        prompt: new Prompt({ text: "Fix the failing tests" }),
+        prompt: Prompt.make({ text: "Fix the failing tests" }),
         resume: false,
       }
 
@@ -255,7 +255,7 @@ describe("SessionV2.prompt", () => {
       const input = {
         sessionID,
         id: messageID,
-        prompt: new Prompt({ text: "Recover committed prompt" }),
+        prompt: Prompt.make({ text: "Recover committed prompt" }),
         resume: false,
       }
       const first = yield* session.prompt(input)
@@ -276,13 +276,13 @@ describe("SessionV2.prompt", () => {
       yield* session.prompt({
         sessionID,
         id: messageID,
-        prompt: new Prompt({ text: "Fix the failing tests" }),
+        prompt: Prompt.make({ text: "Fix the failing tests" }),
       })
       const failure = yield* session
         .prompt({
           sessionID,
           id: messageID,
-          prompt: new Prompt({ text: "Delete the failing tests" }),
+          prompt: Prompt.make({ text: "Delete the failing tests" }),
           resume: false,
         })
         .pipe(Effect.flip)
@@ -301,14 +301,14 @@ describe("SessionV2.prompt", () => {
       yield* session.prompt({
         id: messageID,
         sessionID,
-        prompt: new Prompt({ text: "Fix the failing tests" }),
+        prompt: Prompt.make({ text: "Fix the failing tests" }),
         resume: false,
       })
       const failure = yield* session
         .prompt({
           id: messageID,
           sessionID,
-          prompt: new Prompt({ text: "Fix the failing tests" }),
+          prompt: Prompt.make({ text: "Fix the failing tests" }),
           delivery: "queue",
           resume: false,
         })
@@ -325,7 +325,7 @@ describe("SessionV2.prompt", () => {
       const input = {
         sessionID,
         id: messageID,
-        prompt: new Prompt({ text: "Fix the failing tests" }),
+        prompt: Prompt.make({ text: "Fix the failing tests" }),
         resume: false,
       }
 
@@ -344,7 +344,7 @@ describe("SessionV2.prompt", () => {
       const { db } = yield* Database.Service
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
-      yield* session.prompt({ id: messageID, sessionID, prompt: new Prompt({ text: "Promote once" }), resume: false })
+      yield* session.prompt({ id: messageID, sessionID, prompt: Prompt.make({ text: "Promote once" }), resume: false })
 
       yield* Effect.all(
         [
@@ -368,9 +368,9 @@ describe("SessionV2.prompt", () => {
       const { db } = yield* Database.Service
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
-      const first = yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Before cutoff" }), resume: false })
+      const first = yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Before cutoff" }), resume: false })
       const cutoff = first.admittedSeq
-      const second = yield* session.prompt({ sessionID, prompt: new Prompt({ text: "After cutoff" }), resume: false })
+      const second = yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "After cutoff" }), resume: false })
 
       yield* SessionInput.promoteSteers(db, events, sessionID, cutoff)
 
@@ -386,7 +386,12 @@ describe("SessionV2.prompt", () => {
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
       wakeCalls.length = 0
-      yield* session.prompt({ id: messageID, sessionID, prompt: new Prompt({ text: "Replay pending" }), resume: false })
+      yield* session.prompt({
+        id: messageID,
+        sessionID,
+        prompt: Prompt.make({ text: "Replay pending" }),
+        resume: false,
+      })
       const recorded = yield* db
         .select()
         .from(EventTable)
@@ -422,7 +427,7 @@ describe("SessionV2.prompt", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
-      const prompt = new Prompt({ text: "Historical prompt" })
+      const prompt = Prompt.make({ text: "Historical prompt" })
       yield* events.publish(SessionEvent.Prompted, {
         sessionID,
         messageID,
@@ -443,7 +448,7 @@ describe("SessionV2.prompt", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
-      const prompt = new Prompt({ text: "Historical queued prompt" })
+      const prompt = Prompt.make({ text: "Historical queued prompt" })
       yield* events.publish(SessionEvent.Prompted, {
         sessionID,
         messageID,
@@ -478,7 +483,7 @@ describe("SessionV2.prompt", () => {
         .onConflictDoNothing()
         .run()
         .pipe(Effect.orDie)
-      const prompt = new Prompt({ text: "Fix the failing tests" })
+      const prompt = Prompt.make({ text: "Fix the failing tests" })
 
       yield* session.prompt({ id: messageID, sessionID, prompt, resume: false })
       const failure = yield* session
@@ -502,7 +507,7 @@ describe("SessionV2.prompt", () => {
       })
 
       const failure = yield* session
-        .prompt({ id: messageID, sessionID, prompt: new Prompt({ text: "Conflicting prompt" }), resume: false })
+        .prompt({ id: messageID, sessionID, prompt: Prompt.make({ text: "Conflicting prompt" }), resume: false })
         .pipe(Effect.flip)
 
       expect(failure).toMatchObject({ _tag: "Session.PromptConflictError", sessionID, messageID })
@@ -517,7 +522,7 @@ describe("SessionV2.prompt", () => {
       executionCalls.length = 0
       wakeCalls.length = 0
 
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Run by default" }) })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Run by default" }) })
 
       expect(executionCalls).toEqual([])
       expect(wakeCalls).toEqual([sessionID])
@@ -533,7 +538,7 @@ describe("SessionV2.prompt", () => {
 
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Run explicitly" }),
+        prompt: Prompt.make({ text: "Run explicitly" }),
         resume: true,
       })
 
@@ -549,7 +554,7 @@ describe("SessionV2.prompt", () => {
       executionCalls.length = 0
       wakeCalls.length = 0
 
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Do not run" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Do not run" }), resume: false })
 
       expect(executionCalls).toEqual([])
       expect(wakeCalls).toEqual([])

packages/core/test/session-runner-message.test.ts

@@ -16,7 +16,7 @@ const model = Model.make({ id: "model", provider: "provider", route: OpenAIChat.
 describe("toLLMMessages", () => {
   test("omits empty assistant turns", () => {
     const assistant = (value: string, content: SessionMessage.Assistant["content"]) =>
-      new SessionMessage.Assistant({
+      SessionMessage.Assistant.make({
         id: id(value),
         type: "assistant",
         agent: "build",
@@ -27,13 +27,13 @@ describe("toLLMMessages", () => {
     const messages = toLLMMessages(
       [
         assistant("empty", []),
-        assistant("empty-text", [new SessionMessage.AssistantText({ type: "text", id: "empty", text: "" })]),
+        assistant("empty-text", [SessionMessage.AssistantText.make({ type: "text", id: "empty", text: "" })]),
         assistant("empty-reasoning", [
-          new SessionMessage.AssistantReasoning({ type: "reasoning", id: "empty-reasoning", text: "" }),
+          SessionMessage.AssistantReasoning.make({ type: "reasoning", id: "empty-reasoning", text: "" }),
         ]),
-        assistant("text", [new SessionMessage.AssistantText({ type: "text", id: "text", text: "Partial" })]),
+        assistant("text", [SessionMessage.AssistantText.make({ type: "text", id: "text", text: "Partial" })]),
         assistant("reasoning", [
-          new SessionMessage.AssistantReasoning({
+          SessionMessage.AssistantReasoning.make({
             type: "reasoning",
             id: "reasoning",
             text: "",
@@ -48,43 +48,43 @@ describe("toLLMMessages", () => {
   })
 
   test("maps every top-level V2 Session message type", () => {
-    const file = new FileAttachment({ uri: "data:image/png;base64,aGVsbG8=", mime: "image/png", name: "hello.png" })
+    const file = FileAttachment.make({ uri: "data:image/png;base64,aGVsbG8=", mime: "image/png", name: "hello.png" })
     const messages = toLLMMessages(
       [
-        new SessionMessage.AgentSwitched({
+        SessionMessage.AgentSwitched.make({
           id: id("agent"),
           type: "agent-switched",
           agent: "build",
           time: { created },
         }),
-        new SessionMessage.ModelSwitched({
+        SessionMessage.ModelSwitched.make({
           id: id("model"),
           type: "model-switched",
           model: { id: ModelV2.ID.make("model"), providerID: ProviderV2.ID.make("provider") },
           time: { created },
         }),
-        new SessionMessage.System({
+        SessionMessage.System.make({
           id: id("system"),
           type: "system",
           text: "Updated context\n\nOther context",
           time: { created },
         }),
-        new SessionMessage.User({
+        SessionMessage.User.make({
           id: id("user"),
           type: "user",
           text: "Inspect this image",
           files: [file],
-          agents: [new AgentAttachment({ name: "build" })],
+          agents: [AgentAttachment.make({ name: "build" })],
           time: { created },
         }),
-        new SessionMessage.Synthetic({
+        SessionMessage.Synthetic.make({
           id: id("synthetic"),
           type: "synthetic",
           sessionID: SessionV2.ID.make("ses_translate"),
           text: "Synthetic context",
           time: { created },
         }),
-        new SessionMessage.Shell({
+        SessionMessage.Shell.make({
           id: id("shell"),
           type: "shell",
           callID: "shell-1",
@@ -92,7 +92,7 @@ describe("toLLMMessages", () => {
           output: "/project",
           time: { created, completed: created },
         }),
-        new SessionMessage.Compaction({
+        SessionMessage.Compaction.make({
           id: id("compaction"),
           type: "compaction",
           reason: "auto",
@@ -142,31 +142,31 @@ Recent work
   test("replays durable tool media into canonical tool messages without structured base64", () => {
     const messages = toLLMMessages(
       [
-        new SessionMessage.Assistant({
+        SessionMessage.Assistant.make({
           id: id("assistant"),
           type: "assistant",
           agent: "build",
           model: { id: ModelV2.ID.make("model"), providerID: ProviderV2.ID.make("provider") },
           content: [
-            new SessionMessage.AssistantText({ type: "text", id: "text-1", text: "Checking" }),
-            new SessionMessage.AssistantReasoning({
+            SessionMessage.AssistantText.make({ type: "text", id: "text-1", text: "Checking" }),
+            SessionMessage.AssistantReasoning.make({
               type: "reasoning",
               id: "reasoning-1",
               text: "Think",
               providerMetadata: { anthropic: { signature: "sig_1" } },
             }),
-            new SessionMessage.AssistantTool({
+            SessionMessage.AssistantTool.make({
               type: "tool",
               id: "pending",
               name: "read",
-              state: new SessionMessage.ToolStatePending({ status: "pending", input: '{"path":"README.md"}' }),
+              state: SessionMessage.ToolStatePending.make({ status: "pending", input: '{"path":"README.md"}' }),
               time: { created },
             }),
-            new SessionMessage.AssistantTool({
+            SessionMessage.AssistantTool.make({
               type: "tool",
               id: "running",
               name: "read",
-              state: new SessionMessage.ToolStateRunning({
+              state: SessionMessage.ToolStateRunning.make({
                 status: "running",
                 input: { path: "README.md" },
                 content: [],
@@ -174,11 +174,11 @@ Recent work
               }),
               time: { created },
             }),
-            new SessionMessage.AssistantTool({
+            SessionMessage.AssistantTool.make({
               type: "tool",
               id: "completed",
               name: "read",
-              state: new SessionMessage.ToolStateCompleted({
+              state: SessionMessage.ToolStateCompleted.make({
                 status: "completed",
                 input: { path: "README.md" },
                 content: [
@@ -194,7 +194,7 @@ Recent work
               }),
               time: { created, completed: created },
             }),
-            new SessionMessage.AssistantTool({
+            SessionMessage.AssistantTool.make({
               type: "tool",
               id: "hosted",
               name: "web_search",
@@ -203,7 +203,7 @@ Recent work
                 metadata: { fake: { continuation: "hosted-call" } },
                 resultMetadata: { fake: { continuation: "hosted-result" } },
               },
-              state: new SessionMessage.ToolStateCompleted({
+              state: SessionMessage.ToolStateCompleted.make({
                 status: "completed",
                 input: { query: "Effect" },
                 content: [{ type: "text", text: "Found it" }],
@@ -211,12 +211,12 @@ Recent work
               }),
               time: { created, completed: created },
             }),
-            new SessionMessage.AssistantTool({
+            SessionMessage.AssistantTool.make({
               type: "tool",
               id: "hosted-failed",
               name: "write",
               provider: { executed: true, metadata: { fake: { continuation: "failed" } } },
-              state: new SessionMessage.ToolStateError({
+              state: SessionMessage.ToolStateError.make({
                 status: "error",
                 input: { path: "README.md" },
                 content: [],
@@ -299,13 +299,13 @@ Recent work
   test("restores OpenAI encrypted reasoning metadata", () => {
     const messages = toLLMMessages(
       [
-        new SessionMessage.Assistant({
+        SessionMessage.Assistant.make({
           id: id("assistant-openai-reasoning"),
           type: "assistant",
           agent: "build",
           model: { id: ModelV2.ID.make("model"), providerID: ProviderV2.ID.make("provider") },
           content: [
-            new SessionMessage.AssistantReasoning({
+            SessionMessage.AssistantReasoning.make({
               type: "reasoning",
               id: "reasoning-openai",
               text: "Think",
@@ -330,19 +330,19 @@ Recent work
   test("drops provider-native continuation metadata after a model switch", () => {
     const messages = toLLMMessages(
       [
-        new SessionMessage.Assistant({
+        SessionMessage.Assistant.make({
           id: id("assistant-old-model"),
           type: "assistant",
           agent: "build",
           model: { id: ModelV2.ID.make("old-model"), providerID: ProviderV2.ID.make("provider") },
           content: [
-            new SessionMessage.AssistantReasoning({
+            SessionMessage.AssistantReasoning.make({
               type: "reasoning",
               id: "reasoning-old-model",
               text: "Visible thought",
               providerMetadata: { anthropic: { signature: "sig_old" } },
             }),
-            new SessionMessage.AssistantTool({
+            SessionMessage.AssistantTool.make({
               type: "tool",
               id: "hosted-old-model",
               name: "web_search",
@@ -351,7 +351,7 @@ Recent work
                 metadata: { openai: { itemId: "hosted-old-model" } },
                 resultMetadata: { openai: { itemId: "hosted-old-model" } },
               },
-              state: new SessionMessage.ToolStateCompleted({
+              state: SessionMessage.ToolStateCompleted.make({
                 status: "completed",
                 input: { query: "Effect" },
                 content: [],
@@ -360,7 +360,7 @@ Recent work
               }),
               time: { created, completed: created },
             }),
-            new SessionMessage.AssistantTool({
+            SessionMessage.AssistantTool.make({
               type: "tool",
               id: "local-old-model",
               name: "read",
@@ -369,7 +369,7 @@ Recent work
                 metadata: { fake: { call: "old" } },
                 resultMetadata: { fake: { result: "old" } },
               },
-              state: new SessionMessage.ToolStateCompleted({
+              state: SessionMessage.ToolStateCompleted.make({
                 status: "completed",
                 input: { path: "README.md" },
                 content: [],

packages/core/test/session-runner-recorded.test.ts

@@ -154,7 +154,7 @@ describe("SessionRunnerLLM recorded", () => {
       const session = yield* SessionV2.Service
       const prompt = yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Say hello in one short sentence." }),
+        prompt: Prompt.make({ text: "Say hello in one short sentence." }),
         resume: false,
       })
 

packages/core/test/session-runner.test.ts

@@ -26,7 +26,6 @@ import { SessionMessage } from "@opencode-ai/core/session/message"
 import { Prompt } from "@opencode-ai/core/session/prompt"
 import { SessionProjector } from "@opencode-ai/core/session/projector"
 import { SessionExecution } from "@opencode-ai/core/session/execution"
-import { SessionContextEpoch } from "@opencode-ai/core/session/context-epoch"
 import { SessionRunCoordinator } from "@opencode-ai/core/session/run-coordinator"
 import { SessionRunner } from "@opencode-ai/core/session/runner"
 import * as SessionRunnerLLM from "@opencode-ai/core/session/runner/llm"
@@ -351,7 +350,7 @@ const setupOverflowRecovery = Effect.gen(function* () {
   response = fragmentFixture("text", "text-earlier", ["Earlier answer"]).completeEvents
   yield* session.prompt({
     sessionID,
-    prompt: new Prompt({ text: "Earlier question ".repeat(700) }),
+    prompt: Prompt.make({ text: "Earlier question ".repeat(700) }),
     resume: false,
   })
   yield* session.resume(sessionID)
@@ -476,7 +475,7 @@ const verifyEphemeralDeltas = (kind: FragmentKind) =>
     const chunks = Array.from({ length: 32 }, (_, index) => `${index},`)
     const fixture = fragmentFixture(kind, fragmentID(kind, "many"), chunks)
     const expectedContext = [{ type: "user", text: prompt }, fixture.expectedAssistant]
-    yield* session.prompt({ sessionID, prompt: new Prompt({ text: prompt }), resume: false })
+    yield* session.prompt({ sessionID, prompt: Prompt.make({ text: prompt }), resume: false })
     const events = yield* EventV2.Service
     const live = yield* events.subscribe(fixture.delta).pipe(Stream.take(32), Stream.runCollect, Effect.forkScoped)
     yield* Effect.yieldNow
@@ -507,7 +506,7 @@ const verifyPartialFlushOnFailure = (kind: FragmentKind) =>
     const prompt = `Fail after ${kind}`
     const fixture = fragmentFixture(kind, fragmentID(kind, "partial"), ["Partial"])
     const failure = providerUnavailable()
-    yield* session.prompt({ sessionID, prompt: new Prompt({ text: prompt }), resume: false })
+    yield* session.prompt({ sessionID, prompt: Prompt.make({ text: prompt }), resume: false })
     responseStream = Stream.concat(Stream.fromIterable(fixture.partialEvents), Stream.fail(failure))
 
     expect(yield* session.resume(sessionID).pipe(Effect.flip)).toBe(failure)
@@ -529,7 +528,7 @@ const verifyPartialFlushOnInterruption = (kind: FragmentKind) =>
     const prompt = `Interrupt after ${kind}`
     const fixture = fragmentFixture(kind, fragmentID(kind, "interrupted"), ["Partial"])
     const streamed = yield* Deferred.make<void>()
-    yield* session.prompt({ sessionID, prompt: new Prompt({ text: prompt }), resume: false })
+    yield* session.prompt({ sessionID, prompt: Prompt.make({ text: prompt }), resume: false })
     responseStream = Stream.concat(
       Stream.fromIterable(fixture.partialEvents),
       Stream.fromEffect(Deferred.succeed(streamed, undefined)).pipe(Stream.flatMap(() => Stream.never)),
@@ -573,7 +572,7 @@ describe("SessionRunnerLLM", () => {
             }),
         }),
       })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Use application context" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Use application context" }), resume: false })
       responses = [
         [
           LLMEvent.stepStart({ index: 0 }),
@@ -621,7 +620,7 @@ describe("SessionRunnerLLM", () => {
       streamStarted = undefined
       response = []
 
-      const message = yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Run automatically" }) })
+      const message = yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Run automatically" }) })
 
       expect(requests).toHaveLength(1)
       expect(yield* session.messages({ sessionID })).toMatchObject([
@@ -634,8 +633,8 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
 
       requests.length = 0
       responses = undefined
@@ -662,7 +661,7 @@ describe("SessionRunnerLLM", () => {
       const { db } = yield* Database.Service
       const messageID = SessionMessage.ID.create()
       systemUnavailable = true
-      yield* session.prompt({ id: messageID, sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ id: messageID, sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
       requests.length = 0
 
       const exit = yield* session.resume(sessionID).pipe(Effect.exit)
@@ -680,7 +679,7 @@ describe("SessionRunnerLLM", () => {
       ).toBeUndefined()
 
       systemUnavailable = false
-      yield* session.prompt({ id: messageID, sessionID, prompt: new Prompt({ text: "First" }) })
+      yield* session.prompt({ id: messageID, sessionID, prompt: Prompt.make({ text: "First" }) })
 
       expect(requests).toHaveLength(1)
       expect(requests[0]?.messages.map((message) => message.role)).toEqual(["user"])
@@ -693,7 +692,7 @@ describe("SessionRunnerLLM", () => {
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
       const { db } = yield* Database.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
       requests.length = 0
       response = []
       yield* session.resume(sessionID)
@@ -711,7 +710,7 @@ describe("SessionRunnerLLM", () => {
           .get(),
       ).toBeUndefined()
 
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
       const exit = yield* session.resume(sessionID).pipe(Effect.exit)
 
       expect(Exit.isFailure(exit) && Cause.hasInterruptsOnly(exit.cause)).toBe(true)
@@ -725,7 +724,7 @@ describe("SessionRunnerLLM", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const { db } = yield* Database.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
       response = []
       yield* session.resume(sessionID)
       yield* db
@@ -734,7 +733,7 @@ describe("SessionRunnerLLM", () => {
         .where(eq(SessionContextEpochTable.session_id, sessionID))
         .run()
         .pipe(Effect.orDie)
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
       requests.length = 0
 
       const exit = yield* session.resume(sessionID).pipe(Effect.exit)
@@ -749,13 +748,13 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = []
       yield* session.resume(sessionID)
       systemBaseline = "Changed context"
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests.map((request) => request.system.map((part) => part.text))).toEqual([
@@ -790,7 +789,7 @@ describe("SessionRunnerLLM", () => {
         }),
       )
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = fragmentFixture("text", "text-build", ["Done"]).completeEvents
@@ -816,7 +815,7 @@ describe("SessionRunnerLLM", () => {
         editor.default(AgentV2.ID.make("reviewer"))
       })
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = fragmentFixture("text", "text-reviewer", ["Done"]).completeEvents
@@ -845,7 +844,7 @@ describe("SessionRunnerLLM", () => {
         .run()
         .pipe(Effect.orDie)
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = fragmentFixture("text", "text-selected", ["Done"]).completeEvents
@@ -862,7 +861,7 @@ describe("SessionRunnerLLM", () => {
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
       skillBaselines.set(AgentV2.ID.make("build"), "Build skills")
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = []
@@ -874,7 +873,7 @@ describe("SessionRunnerLLM", () => {
         timestamp: DateTime.makeUnsafe(1),
         agent: "reviewer",
       })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests.map((request) => request.system.map((part) => part.text))).toEqual([
@@ -905,7 +904,7 @@ describe("SessionRunnerLLM", () => {
           })
           .pipe(Effect.asVoid)
       })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = []
@@ -935,7 +934,7 @@ describe("SessionRunnerLLM", () => {
           })
           .pipe(Effect.asVoid)
       })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = []
@@ -949,13 +948,13 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = []
       yield* session.resume(sessionID)
       systemRemoved = true
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests[1]?.messages.map((message) => message.role)).toEqual(["user", "user", "system"])
@@ -971,13 +970,13 @@ describe("SessionRunnerLLM", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = []
       yield* session.resume(sessionID)
       systemBaseline = "Changed context"
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
       yield* session.resume(sessionID)
       yield* events.publish(SessionEvent.ModelSwitched, {
         sessionID,
@@ -986,7 +985,7 @@ describe("SessionRunnerLLM", () => {
         model: { id: ModelV2.ID.make("replacement"), providerID: ProviderV2.ID.make("fake") },
       })
       systemBaseline = "Replacement context"
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Third" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Third" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests.map((request) => request.system.map((part) => part.text))).toEqual([
@@ -1006,7 +1005,7 @@ describe("SessionRunnerLLM", () => {
       ])
       yield* replaySessionProjection(sessionID)
       expect(yield* session.messages({ sessionID })).toHaveLength(6)
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Fourth" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Fourth" }), resume: false })
       yield* session.resume(sessionID)
     }),
   )
@@ -1016,7 +1015,7 @@ describe("SessionRunnerLLM", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = []
@@ -1028,11 +1027,11 @@ describe("SessionRunnerLLM", () => {
         model: { id: ModelV2.ID.make("replacement"), providerID: ProviderV2.ID.make("fake") },
       })
       systemUnavailable = true
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
       yield* session.resume(sessionID)
       systemUnavailable = false
       systemBaseline = "Replacement context"
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Third" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Third" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests.map((request) => request.system.map((part) => part.text))).toEqual([
@@ -1048,7 +1047,7 @@ describe("SessionRunnerLLM", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = []
@@ -1069,7 +1068,7 @@ describe("SessionRunnerLLM", () => {
         recent: "",
       })
       systemBaseline = "Replacement context"
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests.map((request) => request.system.map((part) => part.text))).toEqual([
@@ -1077,7 +1076,7 @@ describe("SessionRunnerLLM", () => {
         ["Replacement context"],
       ])
       yield* replaySessionProjection(sessionID)
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Third" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Third" }), resume: false })
       yield* session.resume(sessionID)
     }),
   )
@@ -1089,7 +1088,7 @@ describe("SessionRunnerLLM", () => {
       response = fragmentFixture("text", "text-first", ["Earlier answer"]).completeEvents
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Earlier question ".repeat(180) }),
+        prompt: Prompt.make({ text: "Earlier question ".repeat(180) }),
         resume: false,
       })
       yield* session.resume(sessionID)
@@ -1102,7 +1101,7 @@ describe("SessionRunnerLLM", () => {
       ]
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Recent exact request ".repeat(180) }),
+        prompt: Prompt.make({ text: "Recent exact request ".repeat(180) }),
         resume: false,
       })
       yield* session.resume(sessionID)
@@ -1128,7 +1127,7 @@ describe("SessionRunnerLLM", () => {
       ]
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Newest exact request ".repeat(180) }),
+        prompt: Prompt.make({ text: "Newest exact request ".repeat(180) }),
         resume: false,
       })
       yield* session.resume(sessionID)
@@ -1156,7 +1155,7 @@ describe("SessionRunnerLLM", () => {
         fragmentFixture("text", "text-summary", ["## Goal\n- Recover overflow"]).completeEvents,
         fragmentFixture("text", "text-final", ["Recovered"]).completeEvents,
       ]
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Continue" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Continue" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests).toHaveLength(3)
@@ -1186,7 +1185,7 @@ describe("SessionRunnerLLM", () => {
         fragmentFixture("text", "text-summary", ["## Goal\n- Recover once"]).completeEvents,
         overflow(),
       ]
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Continue" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Continue" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests).toHaveLength(3)
@@ -1214,7 +1213,7 @@ describe("SessionRunnerLLM", () => {
         fragmentFixture("text", "text-summary", ["## Goal\n- Recover raw overflow"]).completeEvents,
         fragmentFixture("text", "text-final", ["Recovered"]).completeEvents,
       ]
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Continue" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Continue" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests).toHaveLength(3)
@@ -1232,7 +1231,7 @@ describe("SessionRunnerLLM", () => {
         [LLMEvent.providerError({ message: "prompt too long", classification: "context-overflow" })],
         [LLMEvent.providerError({ message: "summary unavailable" })],
       ]
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Continue" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Continue" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests).toHaveLength(2)
@@ -1255,7 +1254,7 @@ describe("SessionRunnerLLM", () => {
       const firstGate = yield* Deferred.make<void>()
       const summaryGate = yield* Deferred.make<void>()
       streamGate = firstGate
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Continue" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Continue" }), resume: false })
       const run = yield* session.resume(sessionID).pipe(Effect.forkChild)
       while (requests.length < 1) yield* Effect.yieldNow
       streamGate = summaryGate
@@ -1275,13 +1274,13 @@ describe("SessionRunnerLLM", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First" }), resume: false })
 
       requests.length = 0
       response = []
       yield* session.resume(sessionID)
       systemBaseline = "Changed context"
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second" }), resume: false })
       yield* session.resume(sessionID)
       const compactionID = SessionMessage.ID.create()
       yield* events.publish(SessionEvent.Compaction.Started, {
@@ -1299,7 +1298,7 @@ describe("SessionRunnerLLM", () => {
         recent: "",
       })
       systemUnavailable = true
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Third" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Third" }), resume: false })
       yield* session.resume(sessionID)
 
       expect(requests.at(-1)?.system.map((part) => part.text)).toEqual(["Initial context"])
@@ -1311,7 +1310,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Use tools" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Use tools" }), resume: false })
 
       requests.length = 0
       responses = undefined
@@ -1409,7 +1408,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Echo this" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Echo this" }), resume: false })
 
       requests.length = 0
       authorizations.length = 0
@@ -1468,7 +1467,7 @@ describe("SessionRunnerLLM", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Echo this" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Echo this" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -1512,7 +1511,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Think first" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Think first" }), resume: false })
 
       requests.length = 0
       response = [
@@ -1550,7 +1549,7 @@ describe("SessionRunnerLLM", () => {
         },
       ])
 
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Continue" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Continue" }), resume: false })
       response = []
       yield* session.resume(sessionID)
 
@@ -1569,7 +1568,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Search first" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Search first" }), resume: false })
 
       requests.length = 0
       response = [
@@ -1594,7 +1593,7 @@ describe("SessionRunnerLLM", () => {
       yield* session.resume(sessionID)
       yield* replaySessionProjection(sessionID)
 
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Continue" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Continue" }), resume: false })
       response = []
       yield* session.resume(sessionID)
 
@@ -1624,7 +1623,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Echo five times" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Echo five times" }), resume: false })
 
       requests.length = 0
       executions.length = 0
@@ -1685,7 +1684,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Echo twice" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Echo twice" }), resume: false })
 
       requests.length = 0
       executions.length = 0
@@ -1773,7 +1772,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Run once" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Run once" }), resume: false })
 
       requests.length = 0
       responses = undefined
@@ -1812,7 +1811,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Start working" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Start working" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -1832,7 +1831,7 @@ describe("SessionRunnerLLM", () => {
 
       const first = yield* session.resume(sessionID).pipe(Effect.forkChild)
       yield* Deferred.await(streamStarted)
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Change direction" }) })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Change direction" }) })
       yield* Deferred.succeed(streamGate, undefined)
       yield* Fiber.join(first)
       streamGate = undefined
@@ -1855,7 +1854,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Start working" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Start working" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -1883,7 +1882,7 @@ describe("SessionRunnerLLM", () => {
       yield* Deferred.await(streamStarted)
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Wait until continuation ends" }),
+        prompt: Prompt.make({ text: "Wait until continuation ends" }),
         delivery: "queue",
       })
       yield* Deferred.succeed(streamGate, undefined)
@@ -1903,7 +1902,7 @@ describe("SessionRunnerLLM", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const { db } = yield* Database.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Interrupt current work" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Interrupt current work" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -1921,7 +1920,7 @@ describe("SessionRunnerLLM", () => {
       yield* Deferred.await(streamStarted)
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Run after interrupt" }),
+        prompt: Prompt.make({ text: "Run after interrupt" }),
         delivery: "queue",
       })
       yield* session.interrupt(sessionID)
@@ -1946,7 +1945,7 @@ describe("SessionRunnerLLM", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const { db } = yield* Database.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Interrupt current work" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Interrupt current work" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -1964,7 +1963,7 @@ describe("SessionRunnerLLM", () => {
       yield* Deferred.await(streamStarted)
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Steer after interrupt" }),
+        prompt: Prompt.make({ text: "Steer after interrupt" }),
       })
       yield* session.interrupt(sessionID)
       expect(yield* Fiber.await(run)).toMatchObject({ _tag: "Failure" })
@@ -1988,7 +1987,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Start working" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Start working" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -2013,8 +2012,8 @@ describe("SessionRunnerLLM", () => {
 
       const first = yield* session.resume(sessionID).pipe(Effect.forkChild)
       yield* Deferred.await(streamStarted)
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Queue first" }), delivery: "queue" })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Queue second" }), delivery: "queue" })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Queue first" }), delivery: "queue" })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Queue second" }), delivery: "queue" })
       yield* Deferred.succeed(streamGate, undefined)
       yield* Fiber.join(first)
       streamGate = undefined
@@ -2031,10 +2030,10 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Start steering" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Start steering" }), resume: false })
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Queue for later" }),
+        prompt: Prompt.make({ text: "Queue for later" }),
         delivery: "queue",
         resume: false,
       })
@@ -2065,7 +2064,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Start working" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Start working" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -2096,13 +2095,13 @@ describe("SessionRunnerLLM", () => {
 
       const first = yield* session.resume(sessionID).pipe(Effect.forkChild)
       while (requests.length < 1) yield* Effect.yieldNow
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Queue first" }), delivery: "queue" })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Queue second" }), delivery: "queue" })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Queue first" }), delivery: "queue" })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Queue second" }), delivery: "queue" })
       streamGate = secondGate
       yield* Deferred.succeed(firstGate, undefined)
       while (requests.length < 2) yield* Effect.yieldNow
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Steer before next queued input" }) })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Also steer before next queued input" }) })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Steer before next queued input" }) })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Also steer before next queued input" }) })
       yield* Deferred.succeed(secondGate, undefined)
       yield* Fiber.join(first)
       streamGate = undefined
@@ -2130,7 +2129,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Start working" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Start working" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -2150,8 +2149,8 @@ describe("SessionRunnerLLM", () => {
 
       const first = yield* session.resume(sessionID).pipe(Effect.forkChild)
       yield* Deferred.await(streamStarted)
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "First steer" }) })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Second steer" }) })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "First steer" }) })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Second steer" }) })
       yield* Deferred.succeed(streamGate, undefined)
       yield* Fiber.join(first)
       streamGate = undefined
@@ -2170,7 +2169,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Start working" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Start working" }), resume: false })
 
       requests.length = 0
       responses = undefined
@@ -2181,7 +2180,7 @@ describe("SessionRunnerLLM", () => {
 
       const first = yield* session.resume(sessionID).pipe(Effect.forkChild)
       yield* Deferred.await(streamStarted)
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Recover with this" }) })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Recover with this" }) })
       yield* Deferred.succeed(streamGate, undefined)
       expect(yield* Fiber.join(first).pipe(Effect.flip)).toBe(streamFailure)
 
@@ -2200,7 +2199,7 @@ describe("SessionRunnerLLM", () => {
       yield* setup
       const session = yield* SessionV2.Service
       const events = yield* EventV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Recover interrupted tool" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Recover interrupted tool" }), resume: false })
       yield* SessionInput.promoteSteers((yield* Database.Service).db, events, sessionID, Number.MAX_SAFE_INTEGER)
       const assistantMessageID = SessionMessage.ID.create()
       yield* events.publish(SessionEvent.Step.Started, {
@@ -2262,7 +2261,7 @@ describe("SessionRunnerLLM", () => {
       const events = yield* EventV2.Service
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Recover interrupted hosted tool" }),
+        prompt: Prompt.make({ text: "Recover interrupted hosted tool" }),
         resume: false,
       })
       yield* SessionInput.promoteSteers((yield* Database.Service).db, events, sessionID, Number.MAX_SAFE_INTEGER)
@@ -2322,7 +2321,7 @@ describe("SessionRunnerLLM", () => {
       const events = yield* EventV2.Service
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Recover interrupted tool input" }),
+        prompt: Prompt.make({ text: "Recover interrupted tool input" }),
         resume: false,
       })
       yield* SessionInput.promoteSteers((yield* Database.Service).db, events, sessionID, Number.MAX_SAFE_INTEGER)
@@ -2360,7 +2359,7 @@ describe("SessionRunnerLLM", () => {
       const session = yield* SessionV2.Service
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Wait in queue" }),
+        prompt: Prompt.make({ text: "Wait in queue" }),
         delivery: "queue",
         resume: false,
       })
@@ -2382,7 +2381,7 @@ describe("SessionRunnerLLM", () => {
       const defect = new Error("fail after prompt promotion")
       let fail = true
       yield* events.project(SessionEvent.Prompted, () => (fail ? Effect.die(defect) : Effect.void))
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Recover promoted input" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Recover promoted input" }), resume: false })
 
       expect(yield* session.resume(sessionID).pipe(Effect.catchDefect(Effect.succeed))).toBe(defect)
       fail = false
@@ -2410,7 +2409,7 @@ describe("SessionRunnerLLM", () => {
       )
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Run committed promotion" }),
+        prompt: Prompt.make({ text: "Run committed promotion" }),
         resume: false,
       })
 
@@ -2427,8 +2426,8 @@ describe("SessionRunnerLLM", () => {
       yield* setup
       yield* insertSession(otherSessionID)
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Run first" }), resume: false })
-      yield* session.prompt({ sessionID: otherSessionID, prompt: new Prompt({ text: "Run second" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Run first" }), resume: false })
+      yield* session.prompt({ sessionID: otherSessionID, prompt: Prompt.make({ text: "Run second" }), resume: false })
 
       requests.length = 0
       responses = undefined
@@ -2470,12 +2469,12 @@ describe("SessionRunnerLLM", () => {
       const session = yield* SessionV2.Service
       yield* session.prompt({
         sessionID: externalSessionID,
-        prompt: new Prompt({ text: "Run external session" }),
+        prompt: Prompt.make({ text: "Run external session" }),
         resume: false,
       })
       yield* session.prompt({
         sessionID: otherExternalSessionID,
-        prompt: new Prompt({ text: "Run other external session" }),
+        prompt: Prompt.make({ text: "Run other external session" }),
         resume: false,
       })
 
@@ -2494,7 +2493,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Retry after failure" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Retry after failure" }), resume: false })
 
       requests.length = 0
       responses = undefined
@@ -2525,7 +2524,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Call missing" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Call missing" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -2571,7 +2570,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Call defect" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Call defect" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -2620,7 +2619,7 @@ describe("SessionRunnerLLM", () => {
             questions.ask({ sessionID: context.sessionID, questions: [] }).pipe(Effect.as({}), Effect.orDie),
         }),
       })
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Ask then stop" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Ask then stop" }), resume: false })
 
       requests.length = 0
       responses = [
@@ -2665,7 +2664,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Settle before failing" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Settle before failing" }), resume: false })
       const failure = providerUnavailable()
       toolExecutionGate = yield* Deferred.make<void>()
       responseStream = Stream.concat(
@@ -2699,7 +2698,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Interrupt blocked tool" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Interrupt blocked tool" }), resume: false })
       executions.length = 0
       toolExecutionGate = yield* Deferred.make<void>()
       responseStream = Stream.concat(
@@ -2749,7 +2748,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Interrupt provider" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Interrupt provider" }), resume: false })
       requests.length = 0
       response = []
       streamGate = yield* Deferred.make<void>()
@@ -2772,7 +2771,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Interrupt tool settlement" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Interrupt tool settlement" }), resume: false })
       executions.length = 0
       toolExecutionGate = yield* Deferred.make<void>()
       response = [
@@ -2815,7 +2814,7 @@ describe("SessionRunnerLLM", () => {
         }),
       )
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Finish at the limit" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Finish at the limit" }), resume: false })
 
       requests.length = 0
       executions.length = 0
@@ -2863,7 +2862,7 @@ describe("SessionRunnerLLM", () => {
         }),
       )
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Start work" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Start work" }), resume: false })
 
       requests.length = 0
       executions.length = 0
@@ -2891,7 +2890,7 @@ describe("SessionRunnerLLM", () => {
 
       const run = yield* session.resume(sessionID).pipe(Effect.forkChild)
       yield* Deferred.await(streamStarted)
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Change direction" }) })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Change direction" }) })
       yield* Deferred.succeed(streamGate, undefined)
       yield* Fiber.join(run)
       streamGate = undefined
@@ -2909,7 +2908,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Fail durably" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Fail durably" }), resume: false })
 
       requests.length = 0
       responses = undefined
@@ -2931,7 +2930,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Fail before step" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Fail before step" }), resume: false })
 
       requests.length = 0
       response = [LLMEvent.providerError({ message: "Provider unavailable" })]
@@ -2950,7 +2949,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Fail after output" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Fail after output" }), resume: false })
 
       requests.length = 0
       response = [
@@ -2979,7 +2978,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Fail raw stream durably" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Fail raw stream durably" }), resume: false })
       const failure = providerUnavailable()
       responseStream = Stream.fail(failure)
 
@@ -2998,7 +2997,7 @@ describe("SessionRunnerLLM", () => {
       const session = yield* SessionV2.Service
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Do not continue failed provider" }),
+        prompt: Prompt.make({ text: "Do not continue failed provider" }),
         resume: false,
       })
 
@@ -3021,7 +3020,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Fail hosted tool durably" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Fail hosted tool durably" }), resume: false })
 
       requests.length = 0
       response = [
@@ -3052,7 +3051,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Fail hosted tool at EOF" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Fail hosted tool at EOF" }), resume: false })
       response = [
         LLMEvent.stepStart({ index: 0 }),
         LLMEvent.toolCall({
@@ -3079,7 +3078,7 @@ describe("SessionRunnerLLM", () => {
       const session = yield* SessionV2.Service
       yield* session.prompt({
         sessionID,
-        prompt: new Prompt({ text: "Fail hosted tool on raw failure" }),
+        prompt: Prompt.make({ text: "Fail hosted tool on raw failure" }),
         resume: false,
       })
       const failure = providerUnavailable()
@@ -3114,7 +3113,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Two blocks" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Two blocks" }), resume: false })
 
       responses = undefined
       streamGate = undefined
@@ -3177,7 +3176,7 @@ describe("SessionRunnerLLM", () => {
     Effect.gen(function* () {
       yield* setup
       const session = yield* SessionV2.Service
-      yield* session.prompt({ sessionID, prompt: new Prompt({ text: "Call provider tool" }), resume: false })
+      yield* session.prompt({ sessionID, prompt: Prompt.make({ text: "Call provider tool" }), resume: false })
 
       responses = undefined
       streamGate = undefined

packages/httpapi-codegen/README.md

@@ -0,0 +1,42 @@
+# @opencode-ai/httpapi-codegen
+
+Build-time source generation for domain-oriented Promise and Effect APIs derived directly from `HttpApi` and Effect Schema contracts.
+
+The package is private while its API is explored. Its tests are the executable specification for the generator. It must remain independent of OpenCode Core and use synthetic `HttpApi` fixtures.
+
+## Settled rules
+
+- Reflect one authoritative `HttpApi` into a shared contract with `compile(Api)`.
+- Emit clients independently with `emitPromise(contract)` and `emitEffect(contract)`.
+- Give each emitter its own public type projection; the shared contract, not a generated type package, is the common source.
+- Generate a rich Effect client with decoded Effect-native values, runtime schemas, preserved transformations, and `HttpApiClient`.
+- Generate a zero-Effect Promise client with structural wire-oriented values, direct `fetch`, and syntax parsing without runtime structural validation.
+- Keep the Promise surface domain-oriented rather than Hey API compatible: methods return unwrapped values and reject with tagged declared errors or `ClientError`.
+- Return Promise streams as lazy `AsyncIterable` values and Effect streams as `Stream` values. Neither runtime reconnects automatically.
+
+- Flatten path, query, header, and payload fields into one input object.
+- Reject duplicate field names across input channels.
+- Emit no method argument for zero fields, an optional object when every field is optional, and a required object when any field is required.
+- Unwrap exact `{ data: A }` success envelopes.
+- Map no-content success to `void`.
+- Preserve other single success values.
+- Reject ambiguous multiple-success contracts.
+- Expose streaming success as `Stream`, not `Effect<Stream>`.
+- Reject schemas whose wire/domain transformation cannot be generated exactly.
+- Map transport, unexpected-status, and response-decoding failures to one stable generated `ClientError`.
+- Commit generated source for review; CI regenerates and fails when the worktree changes.
+- Track generated files in `.httpapi-codegen.json` so regeneration removes only stale files previously owned by the generator.
+
+## Boundary
+
+This package generates only client APIs derived from `HttpApi`. It does not generate embedded-only capabilities. Networked and embedded OpenCode use the same generated Effect client against network and in-memory `HttpClient` transports respectively; the embedded host structurally extends that client with same-process capabilities.
+
+Codegen generates every endpoint in the `HttpApi` it receives. OpenCode owns the product decision by composing the exact remote API before invoking the generator; the generic package has no endpoint filtering policy.
+
+The existing public `generate(Api, { directory })` operation writes the rich Effect output and remains an Effect requiring `FileSystem`. The staged API uses pure `compile(Api)`, `emitEffect(contract)`, and `emitPromise(contract)` phases before `write(output, directory)`. Compiler tests inspect virtual files directly; writer tests use `FileSystem.makeNoop`.
+
+Generation formats TypeScript with Prettier before writing. Output paths are flat, unique, and checked against traversal, reserved manifest names, and existing symbolic links.
+
+Generated source starts with one self-contained module per `HttpApiGroup`, plus root client and index modules. Schema dependencies may be duplicated across group modules. Cross-group schema partitioning is deferred until measured output or bundle cost requires it.
+
+Codegen preserves group and endpoint identifiers exactly. The composed remote `HttpApi` owns public names such as `session` and `get`; the generator performs no prefix stripping, casing conversion, or public-name annotation mapping.

packages/httpapi-codegen/package.json

@@ -0,0 +1,22 @@
+{
+  "$schema": "https://json.schemastore.org/package.json",
+  "name": "@opencode-ai/httpapi-codegen",
+  "private": true,
+  "type": "module",
+  "exports": {
+    ".": "./src/index.ts"
+  },
+  "scripts": {
+    "test": "bun test --timeout 5000 --only-failures",
+    "typecheck": "tsgo --noEmit"
+  },
+  "dependencies": {
+    "effect": "catalog:",
+    "prettier": "3.6.2"
+  },
+  "devDependencies": {
+    "@tsconfig/bun": "catalog:",
+    "@types/bun": "catalog:",
+    "@typescript/native-preview": "catalog:"
+  }
+}

packages/httpapi-codegen/test/effect.ts

@@ -0,0 +1,28 @@
+import { test } from "bun:test"
+import { Cause, Effect, Exit, Layer } from "effect"
+import type { Scope } from "effect/Scope"
+import { TestClock, TestConsole } from "effect/testing"
+
+type Body<A, E, R> = Effect.Effect<A, E, R> | (() => Effect.Effect<A, E, R>)
+
+const layer = Layer.mergeAll(TestConsole.layer, TestClock.layer())
+
+const effect = <A, E>(name: string, body: Body<A, E, Scope>, options?: Parameters<typeof test>[2]) =>
+  test(
+    name,
+    () =>
+      Effect.gen(function* () {
+        const exit = yield* Effect.suspend(() => (typeof body === "function" ? body() : body)).pipe(
+          Effect.scoped,
+          Effect.provide(layer),
+          Effect.exit,
+        )
+        if (Exit.isFailure(exit)) {
+          yield* Effect.forEach(Cause.prettyErrors(exit.cause), Effect.logError, { discard: true })
+        }
+        return yield* exit
+      }).pipe(Effect.runPromise),
+    options,
+  )
+
+export const it = { effect }

packages/httpapi-codegen/test/fixture.ts

@@ -0,0 +1,45 @@
+import { Schema } from "effect"
+import { HttpApi, HttpApiEndpoint, HttpApiGroup, HttpApiSchema } from "effect/unstable/httpapi"
+
+export class Missing extends Schema.TaggedErrorClass<Missing>()("Missing", {
+  message: Schema.String,
+}) {}
+
+export const Api = HttpApi.make("fixture")
+  .add(
+    HttpApiGroup.make("session")
+      .add(HttpApiEndpoint.get("health", "/session/health", { success: Schema.String }))
+      .add(
+        HttpApiEndpoint.get("list", "/session", {
+          query: { archived: Schema.optional(Schema.Boolean) },
+          success: Schema.Array(Schema.String),
+        }),
+      )
+      .add(
+        HttpApiEndpoint.get("get", "/session/:sessionID", {
+          params: { sessionID: Schema.String },
+          success: Schema.Struct({ data: Schema.String }),
+          error: Missing.pipe(HttpApiSchema.status(404)),
+        }),
+      )
+      .add(
+        HttpApiEndpoint.post("interrupt", "/session/:sessionID/interrupt", {
+          params: { sessionID: Schema.String },
+          success: HttpApiSchema.NoContent,
+        }),
+      ),
+  )
+  .add(
+    HttpApiGroup.make("event").add(
+      HttpApiEndpoint.get("subscribe", "/event", {
+        success: HttpApiSchema.StreamSse({ data: Schema.Struct({ type: Schema.String }) }).pipe(
+          HttpApiSchema.status(202),
+        ),
+      }),
+    ),
+  )
+  .add(
+    HttpApiGroup.make("system", { topLevel: true }).add(
+      HttpApiEndpoint.get("status", "/status", { success: Schema.String }),
+    ),
+  )

packages/httpapi-codegen/test/generate.test.ts

@@ -0,0 +1,897 @@
+import { describe, expect, test } from "bun:test"
+import { mkdtemp, rm } from "node:fs/promises"
+import { tmpdir } from "node:os"
+import { join } from "node:path"
+import { Effect, FileSystem, Schema, SchemaAST, SchemaGetter } from "effect"
+import { HttpApi, HttpApiEndpoint, HttpApiGroup, HttpApiMiddleware, HttpApiSchema } from "effect/unstable/httpapi"
+import { format } from "prettier"
+import {
+  compile as compileContract,
+  emitEffect,
+  emitEffectImported,
+  emitPromise,
+  generate,
+  GenerationError,
+} from "../src"
+import { it } from "./effect"
+import { Api as FixtureApi, Missing } from "./fixture"
+
+function api(endpoint: HttpApiEndpoint.Any) {
+  return HttpApi.make("test").add(HttpApiGroup.make("session").add(endpoint))
+}
+
+function compile<Id extends string, Groups extends HttpApiGroup.Any>(source: HttpApi.HttpApi<Id, Groups>) {
+  return emitEffect(compileContract(source))
+}
+
+describe("HttpApiCodegen.generate", () => {
+  test("compiles one contract for Promise and Effect emitters", () => {
+    const contract = compileContract(
+      api(
+        HttpApiEndpoint.get("get", "/session/:sessionID", {
+          params: { sessionID: Schema.String },
+          success: Schema.Struct({ data: Schema.String }),
+        }),
+      ),
+    )
+
+    const promise = emitPromise(contract)
+    const effect = emitEffect(contract)
+
+    expect(promise.operations).toEqual(effect.operations)
+    expect(promise.files.map((file) => file.path)).toEqual(["types.ts", "client-error.ts", "client.ts", "index.ts"])
+    const promiseClient = promise.files.find((file) => file.path === "client.ts")?.content
+    expect(promiseClient).toContain('"get": (input: SessionGetInput, requestOptions?: RequestOptions)')
+    expect(promiseClient).toContain("`/session/${encodeURIComponent(input.sessionID)}`")
+    expect(effect.files.find((file) => file.path === "session.ts")?.content).toContain(
+      'params: { "sessionID": input["sessionID"] }',
+    )
+  })
+
+  test("emits an Effect client against an imported authoritative API", () => {
+    const output = emitEffectImported(
+      compileContract(
+        api(
+          HttpApiEndpoint.get("get", "/session/:sessionID", {
+            params: { sessionID: Schema.String },
+            success: Schema.Struct({ data: Schema.String }),
+          }),
+        ),
+      ),
+      { module: "@example/api", api: "Api" },
+    )
+
+    expect(output.files.map((file) => file.path)).toEqual(["client-error.ts", "client.ts", "index.ts"])
+    expect(output.files.find((file) => file.path === "client.ts")?.content).toContain(
+      'import { Api } from "@example/api"',
+    )
+    expect(output.files.find((file) => file.path === "client.ts")?.content).toContain(
+      "HttpApiClient.ForApi<typeof Api>",
+    )
+  })
+
+  test("projects imported endpoint constants into a generated API", () => {
+    const output = emitEffectImported(
+      compileContract(
+        api(
+          HttpApiEndpoint.get("get", "/session/:sessionID", {
+            params: { sessionID: Schema.String },
+            success: Schema.Struct({ data: Schema.String }),
+          }),
+        ),
+      ),
+      { module: "@example/api", endpoints: { "session.get": "SessionGet" } },
+    )
+    const client = output.files.find((file) => file.path === "client.ts")?.content
+
+    expect(client).toContain('import { SessionGet } from "@example/api"')
+    expect(client).toContain('const Api = HttpApi.make("generated").add(HttpApiGroup.make("session").add(SessionGet))')
+  })
+
+  test("imports an authoritative group without reconstructing it", () => {
+    const output = emitEffectImported(
+      compileContract(
+        api(
+          HttpApiEndpoint.get("get", "/session/:sessionID", {
+            params: { sessionID: Schema.String },
+            success: Schema.String,
+          }),
+        ),
+      ),
+      { module: "@example/api", group: "SessionGroup" },
+    )
+    const client = output.files.find((file) => file.path === "client.ts")?.content
+
+    expect(client).toContain('import { SessionGroup } from "@example/api"')
+    expect(client).toContain('const Api = HttpApi.make("generated").add(SessionGroup)')
+    expect(client).not.toContain("HttpApiGroup")
+  })
+
+  test("separates hosted and consumer group names", () => {
+    const source = HttpApi.make("test").add(
+      HttpApiGroup.make("server.session").add(
+        HttpApiEndpoint.get("session.get", "/session", { success: Schema.String }),
+      ),
+    )
+    const contract = compileContract(source, { groupNames: { "server.session": "sessions" } })
+
+    expect(contract.groups[0]?.identifier).toBe("sessions")
+    expect(contract.groups[0]?.sourceIdentifier).toBe("server.session")
+    expect(contract.groups[0]?.endpoints[0]?.operation).toMatchObject({ group: "sessions", name: "get" })
+  })
+
+  test("rejects consumer group name collisions", () => {
+    const source = HttpApi.make("test")
+      .add(HttpApiGroup.make("first").add(HttpApiEndpoint.get("one", "/one", { success: Schema.String })))
+      .add(HttpApiGroup.make("second").add(HttpApiEndpoint.get("two", "/two", { success: Schema.String })))
+
+    expect(() => compileContract(source, { groupNames: { first: "same", second: "same" } })).toThrow(
+      "Client group name collision: same",
+    )
+  })
+
+  test("uses the unqualified endpoint name for the public client", () => {
+    const contract = compileContract(
+      api(
+        HttpApiEndpoint.get("session.get", "/session/:sessionID", {
+          params: { sessionID: Schema.String },
+          success: Schema.String,
+        }),
+      ),
+    )
+    const promise = emitPromise(contract).files.find((file) => file.path === "client.ts")?.content
+    const effect = emitEffectImported(contract, {
+      module: "@example/api",
+      endpoints: { "session.session.get": "SessionGet" },
+    }).files.find((file) => file.path === "client.ts")?.content
+
+    expect(contract.groups[0]?.endpoints[0]?.operation.name).toBe("get")
+    expect(promise).toContain('"get": (input: SessionGetInput, requestOptions?: RequestOptions)')
+    expect(effect).toContain('const adaptGroup0 = (raw: RawClient["session"]) => ({ "get": Endpoint0_0(raw) })')
+    expect(effect).toContain('raw["session.get"]')
+  })
+
+  test("preserves optional keys in Promise error types", () => {
+    class OptionalError extends Schema.TaggedErrorClass<OptionalError>()(
+      "OptionalError",
+      { message: Schema.String, detail: Schema.String.pipe(Schema.optional) },
+      { httpApiStatus: 400 },
+    ) {}
+    const output = emitPromise(
+      compileContract(api(HttpApiEndpoint.get("get", "/session", { success: Schema.String, error: OptionalError }))),
+    )
+
+    expect(output.files.find((file) => file.path === "types.ts")?.content).toContain(
+      'readonly "message": string; readonly "detail"?: string | undefined',
+    )
+  })
+
+  test("erases brands from Promise wire types", () => {
+    const output = emitPromise(
+      compileContract(
+        api(
+          HttpApiEndpoint.get("get", "/session/:sessionID", {
+            params: { sessionID: Schema.String.pipe(Schema.brand("SessionID")) },
+            success: Schema.Struct({ data: Schema.String.pipe(Schema.brand("SessionID")) }),
+          }),
+        ),
+      ),
+    )
+    const types = output.files.find((file) => file.path === "types.ts")?.content
+
+    expect(types).toContain('readonly "sessionID": string')
+    expect(types).not.toContain("Brand")
+  })
+
+  test("inlines non-recursive references in Promise wire types", () => {
+    const Referenced = Schema.Struct({ value: Schema.String }).annotate({ identifier: "Referenced" })
+    const output = emitPromise(
+      compileContract(
+        api(
+          HttpApiEndpoint.get("get", "/session", {
+            success: Schema.Struct({ data: Referenced }),
+          }),
+        ),
+      ),
+    )
+
+    expect(output.files.find((file) => file.path === "types.ts")?.content).toContain(
+      'export type SessionGetOutput = ({ readonly "data": ({ readonly "value": string }) })["data"]',
+    )
+  })
+
+  test("emits Effect Json schemas as standalone Promise types", () => {
+    const output = emitPromise(
+      compileContract(
+        api(
+          HttpApiEndpoint.get("get", "/session", {
+            success: Schema.Json,
+          }),
+        ),
+      ),
+    )
+    const types = output.files.find((file) => file.path === "types.ts")?.content
+
+    expect(types).toContain("export type JsonValue =")
+    expect(types).toContain("{ readonly [key: string]: JsonValue }")
+    expect(types).not.toContain("Schema.Json")
+  })
+
+  test("emits an optional Promise input when every field is optional", () => {
+    const output = emitPromise(
+      compileContract(
+        api(
+          HttpApiEndpoint.get("list", "/session", {
+            query: { limit: Schema.optional(Schema.Number) },
+            success: Schema.Array(Schema.String),
+          }),
+        ),
+      ),
+    )
+
+    expect(output.files.find((file) => file.path === "client.ts")?.content).toContain(
+      '"list": (input?: SessionListInput, requestOptions?: RequestOptions)',
+    )
+  })
+
+  test("rejects Promise transports that are not implemented", () => {
+    expect(() =>
+      emitPromise(
+        compileContract(
+          api(
+            HttpApiEndpoint.get("text", "/text", {
+              success: Schema.String.pipe(HttpApiSchema.asText()),
+            }),
+          ),
+        ),
+      ),
+    ).toThrow("Unsupported Promise success encoding: session.text")
+
+    expect(() =>
+      emitPromise(
+        compileContract(
+          api(
+            HttpApiEndpoint.get("events", "/events", {
+              success: HttpApiSchema.StreamSse({ data: Schema.String, error: Missing }),
+            }),
+          ),
+        ),
+      ),
+    ).toThrow("Unsupported Promise stream: session.events")
+  })
+
+  test("executes an emitted Promise GET through fetch", async () => {
+    const output = emitPromise(
+      compileContract(
+        api(
+          HttpApiEndpoint.get("get", "/session/:sessionID", {
+            params: { sessionID: Schema.String },
+            success: Schema.Struct({ data: Schema.String }),
+          }),
+        ),
+      ),
+    )
+    const directory = await mkdtemp(join(tmpdir(), "opencode-httpapi-codegen-"))
+
+    try {
+      await Promise.all(output.files.map((file) => Bun.write(join(directory, file.path), file.content)))
+      const generated = await import(`${join(directory, "index.ts")}?t=${crypto.randomUUID()}`)
+      let request: Request | undefined
+      const client = generated.OpenCode.make({
+        baseUrl: "https://example.com",
+        fetch: async (input: RequestInfo | URL) => {
+          request = input instanceof Request ? input : new Request(input)
+          return Response.json({ data: "hello" })
+        },
+      })
+
+      expect(await client.session.get({ sessionID: "a/b" })).toBe("hello")
+      expect(request?.method).toBe("GET")
+      expect(request?.url).toBe("https://example.com/session/a%2Fb")
+    } finally {
+      await rm(directory, { recursive: true, force: true })
+    }
+  })
+
+  test("maps an emitted no-content response to undefined", async () => {
+    const output = emitPromise(
+      compileContract(
+        api(
+          HttpApiEndpoint.post("interrupt", "/session/:sessionID/interrupt", {
+            params: { sessionID: Schema.String },
+            success: HttpApiSchema.NoContent,
+          }),
+        ),
+      ),
+    )
+    const directory = await mkdtemp(join(tmpdir(), "opencode-httpapi-codegen-"))
+
+    try {
+      await Promise.all(output.files.map((file) => Bun.write(join(directory, file.path), file.content)))
+      const generated = await import(`${join(directory, "index.ts")}?t=${crypto.randomUUID()}`)
+      const client = generated.OpenCode.make({
+        baseUrl: "https://example.com",
+        fetch: async () => new Response(null, { status: 204 }),
+      })
+
+      expect(await client.session.interrupt({ sessionID: "session" })).toBeUndefined()
+    } finally {
+      await rm(directory, { recursive: true, force: true })
+    }
+  })
+
+  test("serializes flattened query, header, and JSON payload inputs", async () => {
+    const output = emitPromise(
+      compileContract(
+        api(
+          HttpApiEndpoint.post("prompt", "/session/:sessionID", {
+            params: { sessionID: Schema.String },
+            query: { resume: Schema.optional(Schema.Boolean) },
+            headers: { traceID: Schema.String },
+            payload: Schema.Struct({ prompt: Schema.String }),
+            success: Schema.Struct({ data: Schema.String }),
+          }),
+        ),
+      ),
+    )
+    const directory = await mkdtemp(join(tmpdir(), "opencode-httpapi-codegen-"))
+
+    try {
+      await Promise.all(output.files.map((file) => Bun.write(join(directory, file.path), file.content)))
+      const generated = await import(`${join(directory, "index.ts")}?t=${crypto.randomUUID()}`)
+      let request: Request | undefined
+      const client = generated.OpenCode.make({
+        baseUrl: "https://example.com",
+        fetch: async (input: RequestInfo | URL, init?: RequestInit) => {
+          request = input instanceof Request ? input : new Request(input, init)
+          return Response.json({ data: "admitted" })
+        },
+      })
+
+      expect(
+        await client.session.prompt({ sessionID: "session", resume: true, traceID: "trace", prompt: "hello" }),
+      ).toBe("admitted")
+      expect(request?.url).toBe("https://example.com/session/session?resume=true")
+      expect(request?.headers.get("traceID")).toBe("trace")
+      expect(await request?.json()).toEqual({ prompt: "hello" })
+    } finally {
+      await rm(directory, { recursive: true, force: true })
+    }
+  })
+
+  test("rejects with declared tagged errors and exports a type guard", async () => {
+    const output = emitPromise(
+      compileContract(
+        api(
+          HttpApiEndpoint.get("get", "/session/:sessionID", {
+            params: { sessionID: Schema.String },
+            success: Schema.Struct({ data: Schema.String }),
+            error: Missing.pipe(HttpApiSchema.status(404)),
+          }),
+        ),
+      ),
+    )
+    const directory = await mkdtemp(join(tmpdir(), "opencode-httpapi-codegen-"))
+
+    try {
+      await Promise.all(output.files.map((file) => Bun.write(join(directory, file.path), file.content)))
+      const generated = await import(`${join(directory, "index.ts")}?t=${crypto.randomUUID()}`)
+      const client = generated.OpenCode.make({
+        baseUrl: "https://example.com",
+        fetch: async () => Response.json({ _tag: "Missing", message: "gone" }, { status: 404 }),
+      })
+
+      const error = await client.session.get({ sessionID: "missing" }).catch((cause: unknown) => cause)
+      expect(error).toEqual({ _tag: "Missing", message: "gone" })
+      expect(generated.isMissing(error)).toBeTrue()
+    } finally {
+      await rm(directory, { recursive: true, force: true })
+    }
+  })
+
+  test("iterates an emitted SSE stream lazily without reconnecting", async () => {
+    const output = emitPromise(
+      compileContract(
+        api(
+          HttpApiEndpoint.get("subscribe", "/event", {
+            query: { after: Schema.optional(Schema.Number) },
+            success: HttpApiSchema.StreamSse({ data: Schema.Struct({ type: Schema.String }) }),
+          }),
+        ),
+      ),
+    )
+    const directory = await mkdtemp(join(tmpdir(), "opencode-httpapi-codegen-"))
+
+    try {
+      await Promise.all(output.files.map((file) => Bun.write(join(directory, file.path), file.content)))
+      const generated = await import(`${join(directory, "index.ts")}?t=${crypto.randomUUID()}`)
+      let requests = 0
+      let url: string | undefined
+      const client = generated.OpenCode.make({
+        baseUrl: "https://example.com",
+        fetch: async (input: RequestInfo | URL) => {
+          requests++
+          url = typeof input === "string" ? input : input instanceof URL ? input.href : input.url
+          const encoder = new TextEncoder()
+          return new Response(
+            new ReadableStream({
+              start(controller) {
+                controller.enqueue(encoder.encode('data: {"type":"ready"}\r'))
+                controller.enqueue(encoder.encode("\n\r\n"))
+                controller.close()
+              },
+            }),
+            { headers: { "content-type": "text/event-stream" } },
+          )
+        },
+      })
+      const events = client.session.subscribe({ after: 2 })
+
+      expect(requests).toBe(0)
+      const received = []
+      for await (const event of events) received.push(event)
+      expect(received).toEqual([{ type: "ready" }])
+      expect(requests).toBe(1)
+      expect(url).toBe("https://example.com/event?after=2")
+    } finally {
+      await rm(directory, { recursive: true, force: true })
+    }
+  })
+
+  test("preserves public group and endpoint identifiers exactly", () => {
+    const output = compile(
+      HttpApi.make("test").add(
+        HttpApiGroup.make("session").add(HttpApiEndpoint.get("get", "/session/:sessionID", { success: Schema.String })),
+      ),
+    )
+
+    expect(output.operations[0]).toMatchObject({ group: "session", name: "get" })
+  })
+
+  test("emits one client module per HttpApi group", () => {
+    const source = HttpApi.make("test")
+      .add(HttpApiGroup.make("session").add(HttpApiEndpoint.get("get", "/session", { success: Schema.String })))
+      .add(HttpApiGroup.make("tool").add(HttpApiEndpoint.get("list", "/tool", { success: Schema.String })))
+
+    const output = compile(source)
+
+    expect(output.files.map((file) => file.path)).toEqual([
+      "session.ts",
+      "tool.ts",
+      "client-error.ts",
+      "client.ts",
+      "index.ts",
+    ])
+  })
+
+  test("emits syntactically valid TypeScript modules", () => {
+    const output = compile(
+      api(
+        HttpApiEndpoint.get("get", "/session/:sessionID", {
+          params: { sessionID: Schema.String },
+          success: Schema.Struct({ data: Schema.String }),
+        }),
+      ),
+    )
+    const transpiler = new Bun.Transpiler({ loader: "ts" })
+
+    for (const file of output.files) expect(() => transpiler.transformSync(file.content)).not.toThrow()
+  })
+
+  it.effect("keeps the strict generated-consumer fixture current", () =>
+    Effect.gen(function* () {
+      const output = compile(FixtureApi)
+      const actual = yield* Effect.promise(() =>
+        Array.fromAsync(new Bun.Glob("*.ts").scan(new URL("generated", import.meta.url).pathname)),
+      )
+      expect(actual.sort((a, b) => a.localeCompare(b))).toEqual(
+        output.files.map((file) => file.path).sort((a, b) => a.localeCompare(b)),
+      )
+      yield* Effect.forEach(output.files, (file) =>
+        Effect.tryPromise(() =>
+          Promise.all([
+            Bun.file(new URL(`generated/${file.path}`, import.meta.url)).text(),
+            format(file.content, { parser: "typescript", semi: false, printWidth: 120 }),
+          ]),
+        ).pipe(Effect.map(([content, expected]) => expect(content).toBe(expected))),
+      )
+    }),
+  )
+
+  test("flattens transport input channels into one domain input", () => {
+    const output = compile(
+      api(
+        HttpApiEndpoint.post("prompt", "/session/:sessionID", {
+          params: { sessionID: Schema.String },
+          query: { resume: Schema.String },
+          headers: { traceID: Schema.String },
+          payload: Schema.Struct({ prompt: Schema.String }),
+          success: Schema.Struct({ data: Schema.String }),
+        }),
+      ),
+    )
+
+    expect(output.operations[0]?.input).toEqual([
+      { name: "sessionID", source: "params" },
+      { name: "resume", source: "query" },
+      { name: "traceID", source: "headers" },
+      { name: "prompt", source: "payload" },
+    ])
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain(
+      'params: { "sessionID": input["sessionID"] }',
+    )
+  })
+
+  test("uses no argument when an operation has no input fields", () => {
+    const output = compile(api(HttpApiEndpoint.get("health", "/health", { success: Schema.String })))
+
+    expect(output.operations[0]?.inputMode).toBe("none")
+  })
+
+  test("uses an optional object when every input field is optional", () => {
+    const output = compile(
+      api(
+        HttpApiEndpoint.get("list", "/session", {
+          query: { limit: Schema.optional(Schema.String) },
+          success: Schema.Array(Schema.String),
+        }),
+      ),
+    )
+
+    expect(output.operations[0]?.inputMode).toBe("optional")
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain('input?.["limit"]')
+  })
+
+  test("regenerates standard HttpApi transport codecs from decoded schemas", () => {
+    const output = compile(
+      api(
+        HttpApiEndpoint.get("list", "/session", {
+          query: { archived: Schema.optional(Schema.Boolean) },
+          success: Schema.String,
+        }),
+      ),
+    )
+
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain("Schema.Boolean")
+  })
+
+  test("uses a required object when any input field is required", () => {
+    const output = compile(
+      api(
+        HttpApiEndpoint.get("get", "/session/:sessionID", {
+          params: { sessionID: Schema.String },
+          query: { includeArchived: Schema.optional(Schema.String) },
+          success: Schema.String,
+        }),
+      ),
+    )
+
+    expect(output.operations[0]?.inputMode).toBe("required")
+  })
+
+  test("rejects colliding input names across transport channels", () => {
+    expect(() =>
+      compile(
+        api(
+          HttpApiEndpoint.post("prompt", "/session/:id", {
+            params: { id: Schema.String },
+            payload: Schema.Struct({ id: Schema.String }),
+            success: Schema.Void,
+          }),
+        ),
+      ),
+    ).toThrow("Input field collision: id")
+  })
+
+  test("rejects multiple payload alternatives until selection semantics are explicit", () => {
+    expect(() =>
+      compile(
+        api(
+          HttpApiEndpoint.post("prompt", "/session", {
+            payload: [Schema.Struct({ text: Schema.String }), Schema.Struct({ count: Schema.Number })],
+            success: Schema.String,
+          }),
+        ),
+      ),
+    ).toThrow("Multiple payload schemas: session.prompt")
+  })
+
+  test("unwraps an exact data success envelope", () => {
+    const output = compile(
+      api(
+        HttpApiEndpoint.get("get", "/session/:sessionID", {
+          params: { sessionID: Schema.String },
+          success: Schema.Struct({ data: Schema.String }),
+        }),
+      ),
+    )
+
+    expect(output.operations[0]?.success).toBe("value")
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain(
+      "Effect.map((value) => value.data)",
+    )
+  })
+
+  test("maps no-content success to void", () => {
+    const output = compile(
+      api(HttpApiEndpoint.post("interrupt", "/session/:sessionID/interrupt", { success: HttpApiSchema.NoContent })),
+    )
+
+    expect(output.operations[0]?.success).toBe("void")
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain('"httpApiStatus": 204')
+  })
+
+  test("preserves non-default empty response statuses", () => {
+    const output = compile(api(HttpApiEndpoint.post("create", "/session", { success: HttpApiSchema.Created })))
+
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain('"httpApiStatus": 201')
+  })
+
+  test("returns a non-envelope success unchanged", () => {
+    const output = compile(api(HttpApiEndpoint.get("health", "/health", { success: Schema.String })))
+
+    expect(output.operations[0]?.success).toBe("value")
+  })
+
+  test("rejects multiple success shapes until their public semantics are explicit", () => {
+    expect(() =>
+      compile(
+        api(
+          HttpApiEndpoint.get("get", "/session", {
+            success: [Schema.String, Schema.Number],
+          }),
+        ),
+      ),
+    ).toThrow("Multiple success schemas: session.get")
+  })
+
+  test("models an SSE success as a direct stream", () => {
+    const output = compile(
+      api(
+        HttpApiEndpoint.get("subscribe", "/event", {
+          success: HttpApiSchema.StreamSse({ data: Schema.Struct({ type: Schema.String }) }),
+        }),
+      ),
+    )
+
+    expect(output.operations[0]?.success).toBe("stream")
+  })
+
+  test("preserves annotated stream response statuses", () => {
+    const output = compile(
+      api(
+        HttpApiEndpoint.get("subscribe", "/event", {
+          success: HttpApiSchema.StreamSse({ data: Schema.String }).pipe(HttpApiSchema.status(202)),
+        }),
+      ),
+    )
+
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain(
+      ".pipe(HttpApiSchema.status(202))",
+    )
+  })
+
+  test("rejects schemas whose semantics cannot be emitted exactly", () => {
+    const OpaqueUrl = Schema.declare((input): input is URL => input instanceof URL)
+
+    expect(() => compile(api(HttpApiEndpoint.get("get", "/url", { success: OpaqueUrl })))).toThrow(
+      "Unportable schema: session.get.success",
+    )
+  })
+
+  test("rejects custom transformations hidden beneath standard HttpApi codecs", () => {
+    const QueryBoolean = Schema.Literals(["yes", "no"]).pipe(
+      Schema.decodeTo(Schema.Boolean, {
+        decode: SchemaGetter.transform((value) => value === "yes"),
+        encode: SchemaGetter.transform((value) => (value ? "yes" : "no")),
+      }),
+    )
+
+    expect(() =>
+      compile(
+        api(
+          HttpApiEndpoint.get("get", "/session", {
+            query: { archived: QueryBoolean },
+            success: Schema.String,
+          }),
+        ),
+      ),
+    ).toThrow("Effect schema requires authoritative import: session.get")
+  })
+
+  test("rejects custom validation checks without portable metadata", () => {
+    const Positive = Schema.Number.check(Schema.makeFilter((value) => (value > 0 ? undefined : "positive")))
+
+    expect(() => compile(api(HttpApiEndpoint.get("get", "/session", { success: Positive })))).toThrow(
+      "Unportable schema: session.get.success",
+    )
+  })
+
+  test("rejects spoofed and aborted validation checks", () => {
+    const Spoofed = Schema.Number.check(
+      Schema.makeFilter(() => "always fails", { meta: { _tag: "isFinite" }, arbitrary: {} }),
+    )
+    const Aborted = Schema.Number.check(Schema.isFinite().abort())
+
+    expect(() => compile(api(HttpApiEndpoint.get("spoofed", "/session", { success: Spoofed })))).toThrow(
+      "Unportable schema: session.spoofed.success",
+    )
+    expect(() => compile(api(HttpApiEndpoint.get("aborted", "/session", { success: Aborted })))).toThrow(
+      "Unportable schema: session.aborted.success",
+    )
+  })
+
+  test("rejects altered wire-side schemas even when the codec transformation is canonical", () => {
+    const JsonNumber = Schema.toCodecJson(Schema.Number)
+    const link = JsonNumber.ast.encoding?.[0]
+    if (link === undefined) throw new Error("Expected JSON number encoding")
+    // This helper is present at runtime but omitted from the public declaration surface.
+    const replaceEncoding: unknown = Reflect.get(SchemaAST, "replaceEncoding")
+    if (typeof replaceEncoding !== "function") throw new Error("Expected SchemaAST.replaceEncoding")
+    const ast: unknown = replaceEncoding(JsonNumber.ast, [
+      new SchemaAST.Link(Schema.String.check(Schema.isMinLength(2)).ast, link.transformation),
+    ])
+    if (!SchemaAST.isAST(ast)) throw new Error("Expected altered schema AST")
+    const Altered = Schema.make(ast)
+
+    expect(() => compile(api(HttpApiEndpoint.get("get", "/session", { success: Altered })))).toThrow(
+      "Effect schema requires authoritative import: session.get",
+    )
+  })
+
+  test("rejects lexical generation and annotation values", () => {
+    const Generated = Schema.declare((input): input is string => typeof input === "string").annotate({
+      generation: { runtime: "LocalOnly", Type: "string" },
+    })
+    const Annotated = Schema.declare((input): input is string => typeof input === "string").annotate({
+      custom: () => "local",
+    })
+
+    expect(() => compile(api(HttpApiEndpoint.get("generated", "/session", { success: Generated })))).toThrow(
+      "Unportable schema: session.generated.success",
+    )
+    expect(() => compile(api(HttpApiEndpoint.get("annotated", "/session", { success: Annotated })))).toThrow(
+      "Unportable schema: session.annotated.success",
+    )
+  })
+
+  test("preserves errors from server-only middleware", () => {
+    class Unauthorized extends Schema.TaggedErrorClass<Unauthorized>()("Unauthorized", {}) {}
+    class Authorization extends HttpApiMiddleware.Service<Authorization>()("Authorization", {
+      error: Unauthorized,
+    }) {}
+
+    const output = compile(
+      api(HttpApiEndpoint.get("get", "/session", { success: Schema.String }).middleware(Authorization)),
+    )
+
+    expect(output.operations[0]).toBeDefined()
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain(
+      'extends Schema.TaggedErrorClass<Endpoint0Error0Class>("Unauthorized")',
+    )
+  })
+
+  test("preserves tagged error response statuses", () => {
+    class Missing extends Schema.TaggedErrorClass<Missing>()("Missing", {}) {}
+    const output = compile(
+      api(
+        HttpApiEndpoint.get("get", "/session", {
+          success: Schema.String,
+          error: Missing.pipe(HttpApiSchema.status(404)),
+        }),
+      ),
+    )
+
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain(
+      'Endpoint0Error0Class.annotate({ "httpApiStatus": 404 })',
+    )
+  })
+
+  test("supports every HttpApi method through the generic constructor", () => {
+    const output = compile(api(HttpApiEndpoint.make("TRACE")("trace", "/trace", { success: Schema.String })))
+
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain('HttpApiEndpoint.make("TRACE")')
+  })
+
+  test("uses safe unique module paths without changing public group identifiers", () => {
+    const output = compile(
+      HttpApi.make("test")
+        .add(HttpApiGroup.make("../session").add(HttpApiEndpoint.get("get", "/session", { success: Schema.String })))
+        .add(HttpApiGroup.make("GROUP-0").add(HttpApiEndpoint.get("list", "/session", { success: Schema.String }))),
+    )
+
+    expect(output.files.slice(0, 2).map((file) => file.path)).toEqual(["group-0.ts", "GROUP-0-1.ts"])
+    expect(output.files[0]?.content).toContain('HttpApiGroup.make("../session"')
+  })
+
+  test("reserves support module names case-insensitively", () => {
+    const output = compile(
+      HttpApi.make("test")
+        .add(HttpApiGroup.make("client").add(HttpApiEndpoint.get("get", "/client", { success: Schema.String })))
+        .add(HttpApiGroup.make("INDEX").add(HttpApiEndpoint.get("get", "/index", { success: Schema.String }))),
+    )
+
+    expect(output.files.slice(0, 2).map((file) => file.path)).toEqual(["client-0.ts", "INDEX-1.ts"])
+  })
+
+  test("keeps searching when a reserved-name fallback is also occupied", () => {
+    const output = compile(
+      HttpApi.make("test")
+        .add(HttpApiGroup.make("client-1").add(HttpApiEndpoint.get("first", "/first", { success: Schema.String })))
+        .add(HttpApiGroup.make("client").add(HttpApiEndpoint.get("second", "/second", { success: Schema.String }))),
+    )
+
+    expect(output.files.slice(0, 2).map((file) => file.path)).toEqual(["client-1.ts", "client-1-1.ts"])
+  })
+
+  test("rejects collisions in the flattened client namespace", () => {
+    expect(() =>
+      compile(
+        HttpApi.make("test")
+          .add(HttpApiGroup.make("status").add(HttpApiEndpoint.get("get", "/nested", { success: Schema.String })))
+          .add(
+            HttpApiGroup.make("system", { topLevel: true }).add(
+              HttpApiEndpoint.get("status", "/status", { success: Schema.String }),
+            ),
+          ),
+      ),
+    ).toThrow("Client name collision: status")
+  })
+
+  test("emits a usable raw type for top-level groups", () => {
+    const output = compile(
+      HttpApi.make("test").add(
+        HttpApiGroup.make("health", { topLevel: true }).add(
+          HttpApiEndpoint.get("check", "/health", { success: Schema.String }),
+        ),
+      ),
+    )
+
+    expect(output.files[0]?.content).toContain("type RawGroup = HttpApiClient.Client<typeof Group0")
+  })
+
+  it.effect("reports compiler failures in the generate Effect", () =>
+    Effect.gen(function* () {
+      const error = yield* generate(
+        api(
+          HttpApiEndpoint.get("get", "/url", {
+            success: Schema.declare((input): input is URL => input instanceof URL),
+          }),
+        ),
+        {
+          directory: "/generated",
+        },
+      ).pipe(Effect.flip)
+
+      expect(error).toBeInstanceOf(GenerationError)
+      if (error instanceof GenerationError) expect(error.reason).toBe("Unportable schema: session.get.success")
+    }).pipe(Effect.provideService(FileSystem.FileSystem, FileSystem.makeNoop({}))),
+  )
+
+  test("rejects required client middleware without an adapter", () => {
+    class SignedRequest extends HttpApiMiddleware.Service<SignedRequest>()("SignedRequest", {
+      requiredForClient: true,
+    }) {}
+
+    expect(() =>
+      compile(api(HttpApiEndpoint.get("get", "/session", { success: Schema.String }).middleware(SignedRequest))),
+    ).toThrow("Client middleware requires adapter: SignedRequest")
+  })
+
+  test("maps transport and decode failures to one stable client error", () => {
+    const output = compile(
+      api(
+        HttpApiEndpoint.get("get", "/session", {
+          success: Schema.String,
+        }),
+      ),
+    )
+
+    expect(output.operations[0]?.errors).toContain("ClientError")
+    expect(output.operations[0]?.errors).not.toContain("HttpClientError")
+    expect(output.operations[0]?.errors).not.toContain("SchemaError")
+    expect(output.files.find((file) => file.path === "session.ts")?.content).toContain(
+      "new ClientError({ cause: error })",
+    )
+  })
+})

packages/httpapi-codegen/test/generated-consumer.ts

@@ -0,0 +1,28 @@
+import { Effect, Stream } from "effect"
+import { HttpClient } from "effect/unstable/http"
+import { ClientError, OpenCode } from "./generated"
+import { Missing } from "./fixture"
+
+export const program = OpenCode.make().pipe(
+  Effect.map((client) => {
+    const health = client.session.health()
+    const list = client.session.list()
+    const filtered = client.session.list({ archived: true })
+    const get = client.session.get({ sessionID: "session" })
+    const interrupt = client.session.interrupt({ sessionID: "session" })
+    const status = client.status()
+    const subscribe = client.event.subscribe()
+
+    const _health: Effect.Effect<string, ClientError> = health
+    const _list: Effect.Effect<ReadonlyArray<string>, ClientError> = list
+    const _filtered: Effect.Effect<ReadonlyArray<string>, ClientError> = filtered
+    const _get: Effect.Effect<string, Missing | ClientError> = get
+    const _interrupt: Effect.Effect<void, ClientError> = interrupt
+    const _status: Effect.Effect<string, ClientError> = status
+    const _subscribe: Stream.Stream<{ readonly type: string }, ClientError> = subscribe
+
+    return { _health, _list, _filtered, _get, _interrupt, _status, _subscribe }
+  }),
+)
+
+const _requiresHttpClient: Effect.Effect<unknown, never, HttpClient.HttpClient> = program

packages/httpapi-codegen/test/generated/client-error.ts

@@ -0,0 +1,5 @@
+import { Schema } from "effect"
+
+export class ClientError extends Schema.TaggedErrorClass<ClientError>()("ClientError", {
+  cause: Schema.Defect(),
+}) {}

packages/httpapi-codegen/test/generated/client.ts

@@ -0,0 +1,16 @@
+// Generated by @opencode-ai/httpapi-codegen. Do not edit.
+import { Effect } from "effect"
+import { HttpApi, HttpApiClient } from "effect/unstable/httpapi"
+import { adaptGroup0, Group0 } from "./session"
+import { adaptGroup1, Group1 } from "./event"
+import { adaptGroup2, Group2 } from "./system"
+
+const Api = HttpApi.make("generated").add(Group0).add(Group1).add(Group2)
+const adaptClient = (raw: HttpApiClient.ForApi<typeof Api>) => ({
+  session: adaptGroup0(raw["session"]),
+  event: adaptGroup1(raw["event"]),
+  ...adaptGroup2({ status: raw["status"] }),
+})
+
+export const make = (options?: { readonly baseUrl?: URL | string }) =>
+  HttpApiClient.make(Api, options).pipe(Effect.map(adaptClient))

packages/httpapi-codegen/test/generated/event.ts

@@ -0,0 +1,39 @@
+// Generated by @opencode-ai/httpapi-codegen. Do not edit.
+import { Effect, Schema, Stream } from "effect"
+import { Sse } from "effect/unstable/encoding"
+import { HttpClientError } from "effect/unstable/http"
+import { HttpApiClient, HttpApiEndpoint, HttpApiGroup, HttpApiSchema } from "effect/unstable/httpapi"
+import { ClientError } from "./client-error"
+
+const Endpoint0SuccessData = Schema.Struct({ type: Schema.String })
+
+const Endpoint0SuccessError = Schema.Never
+
+export const Group1 = HttpApiGroup.make("event", { topLevel: false }).add(
+  HttpApiEndpoint.make("GET")("subscribe", "/event", {
+    success: HttpApiSchema.StreamSse({
+      data: Endpoint0SuccessData,
+      error: Endpoint0SuccessError,
+      contentType: "text/event-stream",
+    }).pipe(HttpApiSchema.status(202)),
+  }),
+)
+
+type RawGroup = HttpApiClient.Client.Group<typeof Group1, "event", never, never>
+
+const Endpoint0DeclaredError = Schema.Union([Endpoint0SuccessError])
+const mapEndpoint0Error = (error: unknown) =>
+  HttpClientError.isHttpClientError(error) || Schema.isSchemaError(error) || Sse.Retry.is(error)
+    ? new ClientError({ cause: error })
+    : Schema.is(Endpoint0DeclaredError)(error)
+      ? error
+      : new ClientError({ cause: error })
+const Endpoint0 = (raw: RawGroup) => () =>
+  Stream.unwrap(
+    raw["subscribe"]({}).pipe(
+      Effect.mapError(mapEndpoint0Error),
+      Effect.map((stream) => stream.pipe(Stream.mapError(mapEndpoint0Error))),
+    ),
+  )
+
+export const adaptGroup1 = (raw: RawGroup) => ({ subscribe: Endpoint0(raw) })

packages/httpapi-codegen/test/generated/index.ts

@@ -0,0 +1,2 @@
+export { ClientError } from "./client-error"
+export * as OpenCode from "./client"

packages/httpapi-codegen/test/generated/session.ts

@@ -0,0 +1,96 @@
+// Generated by @opencode-ai/httpapi-codegen. Do not edit.
+import { Effect, Schema } from "effect"
+import { Sse } from "effect/unstable/encoding"
+import { HttpClientError } from "effect/unstable/http"
+import { HttpApiClient, HttpApiEndpoint, HttpApiGroup } from "effect/unstable/httpapi"
+import { ClientError } from "./client-error"
+
+const Endpoint0Success = Schema.String
+
+const Endpoint1Query = Schema.Struct({ archived: Schema.optionalKey(Schema.Union([Schema.Boolean, Schema.Undefined])) })
+
+const Endpoint1Success = Schema.Array(Schema.String)
+
+const Endpoint2Params = Schema.Struct({ sessionID: Schema.String })
+
+const Endpoint2Success = Schema.Struct({ data: Schema.String })
+
+class Endpoint2Error0Class extends Schema.TaggedErrorClass<Endpoint2Error0Class>("Missing")("Missing", {
+  message: Schema.String,
+}) {}
+const Endpoint2Error0 = Endpoint2Error0Class.annotate({ httpApiStatus: 404 })
+
+const Endpoint3Params = Schema.Struct({ sessionID: Schema.String })
+
+const Endpoint3Success = Schema.Void.annotate({ httpApiStatus: 204 })
+
+export const Group0 = HttpApiGroup.make("session", { topLevel: false })
+  .add(HttpApiEndpoint.make("GET")("health", "/session/health", { success: Endpoint0Success }))
+  .add(HttpApiEndpoint.make("GET")("list", "/session", { query: Endpoint1Query, success: Endpoint1Success }))
+  .add(
+    HttpApiEndpoint.make("GET")("get", "/session/:sessionID", {
+      params: Endpoint2Params,
+      success: Endpoint2Success,
+      error: Endpoint2Error0,
+    }),
+  )
+  .add(
+    HttpApiEndpoint.make("POST")("interrupt", "/session/:sessionID/interrupt", {
+      params: Endpoint3Params,
+      success: Endpoint3Success,
+    }),
+  )
+
+type RawGroup = HttpApiClient.Client.Group<typeof Group0, "session", never, never>
+
+const Endpoint0DeclaredError = Schema.Never
+const mapEndpoint0Error = (error: unknown) =>
+  HttpClientError.isHttpClientError(error) || Schema.isSchemaError(error) || Sse.Retry.is(error)
+    ? new ClientError({ cause: error })
+    : Schema.is(Endpoint0DeclaredError)(error)
+      ? error
+      : new ClientError({ cause: error })
+const Endpoint0 = (raw: RawGroup) => () => raw["health"]({}).pipe(Effect.mapError(mapEndpoint0Error))
+
+type Endpoint1Input = { readonly archived?: (typeof Endpoint1Query.Type)["archived"] }
+const Endpoint1DeclaredError = Schema.Never
+const mapEndpoint1Error = (error: unknown) =>
+  HttpClientError.isHttpClientError(error) || Schema.isSchemaError(error) || Sse.Retry.is(error)
+    ? new ClientError({ cause: error })
+    : Schema.is(Endpoint1DeclaredError)(error)
+      ? error
+      : new ClientError({ cause: error })
+const Endpoint1 = (raw: RawGroup) => (input?: Endpoint1Input) =>
+  raw["list"]({ query: { archived: input?.["archived"] } }).pipe(Effect.mapError(mapEndpoint1Error))
+
+type Endpoint2Input = { readonly sessionID: (typeof Endpoint2Params.Type)["sessionID"] }
+const Endpoint2DeclaredError = Schema.Union([Endpoint2Error0])
+const mapEndpoint2Error = (error: unknown) =>
+  HttpClientError.isHttpClientError(error) || Schema.isSchemaError(error) || Sse.Retry.is(error)
+    ? new ClientError({ cause: error })
+    : Schema.is(Endpoint2DeclaredError)(error)
+      ? error
+      : new ClientError({ cause: error })
+const Endpoint2 = (raw: RawGroup) => (input: Endpoint2Input) =>
+  raw["get"]({ params: { sessionID: input["sessionID"] } }).pipe(
+    Effect.mapError(mapEndpoint2Error),
+    Effect.map((value) => value.data),
+  )
+
+type Endpoint3Input = { readonly sessionID: (typeof Endpoint3Params.Type)["sessionID"] }
+const Endpoint3DeclaredError = Schema.Never
+const mapEndpoint3Error = (error: unknown) =>
+  HttpClientError.isHttpClientError(error) || Schema.isSchemaError(error) || Sse.Retry.is(error)
+    ? new ClientError({ cause: error })
+    : Schema.is(Endpoint3DeclaredError)(error)
+      ? error
+      : new ClientError({ cause: error })
+const Endpoint3 = (raw: RawGroup) => (input: Endpoint3Input) =>
+  raw["interrupt"]({ params: { sessionID: input["sessionID"] } }).pipe(Effect.mapError(mapEndpoint3Error))
+
+export const adaptGroup0 = (raw: RawGroup) => ({
+  health: Endpoint0(raw),
+  list: Endpoint1(raw),
+  get: Endpoint2(raw),
+  interrupt: Endpoint3(raw),
+})

packages/httpapi-codegen/test/generated/system.ts

@@ -0,0 +1,25 @@
+// Generated by @opencode-ai/httpapi-codegen. Do not edit.
+import { Effect, Schema } from "effect"
+import { Sse } from "effect/unstable/encoding"
+import { HttpClientError } from "effect/unstable/http"
+import { HttpApiClient, HttpApiEndpoint, HttpApiGroup } from "effect/unstable/httpapi"
+import { ClientError } from "./client-error"
+
+const Endpoint0Success = Schema.String
+
+export const Group2 = HttpApiGroup.make("system", { topLevel: true }).add(
+  HttpApiEndpoint.make("GET")("status", "/status", { success: Endpoint0Success }),
+)
+
+type RawGroup = HttpApiClient.Client<typeof Group2>
+
+const Endpoint0DeclaredError = Schema.Never
+const mapEndpoint0Error = (error: unknown) =>
+  HttpClientError.isHttpClientError(error) || Schema.isSchemaError(error) || Sse.Retry.is(error)
+    ? new ClientError({ cause: error })
+    : Schema.is(Endpoint0DeclaredError)(error)
+      ? error
+      : new ClientError({ cause: error })
+const Endpoint0 = (raw: RawGroup) => () => raw["status"]({}).pipe(Effect.mapError(mapEndpoint0Error))
+
+export const adaptGroup2 = (raw: RawGroup) => ({ status: Endpoint0(raw) })

packages/httpapi-codegen/test/write.test.ts

@@ -0,0 +1,160 @@
+import { describe, expect } from "bun:test"
+import { Effect, FileSystem, Option } from "effect"
+import { write, type Output } from "../src"
+import { it } from "./effect"
+
+describe("HttpApiCodegen.write", () => {
+  it.effect("writes compiled files beneath the output directory", () => {
+    const writes: Array<{ readonly path: string; readonly content: string }> = []
+    const output: Output = {
+      operations: [],
+      files: [{ path: "session.ts", content: "export const session = {}" }],
+    }
+
+    return Effect.gen(function* () {
+      yield* write(output, "/generated")
+
+      expect(writes).toEqual([
+        { path: "/generated/session.ts", content: "export const session = {}\n" },
+        { path: "/generated/.httpapi-codegen.json", content: '[\n  "session.ts"\n]\n' },
+      ])
+    }).pipe(
+      Effect.provideService(
+        FileSystem.FileSystem,
+        FileSystem.makeNoop({
+          exists: () => Effect.succeed(false),
+          makeDirectory: () => Effect.void,
+          writeFileString: (path, content) => {
+            writes.push({ path, content })
+            return Effect.void
+          },
+        }),
+      ),
+    )
+  })
+
+  it.effect("removes only stale files owned by the previous manifest", () => {
+    const removed: Array<string> = []
+    return write(
+      {
+        operations: [],
+        files: [{ path: "session.ts", content: "" }],
+      },
+      "/generated",
+    ).pipe(
+      Effect.provideService(
+        FileSystem.FileSystem,
+        FileSystem.makeNoop({
+          exists: (path) => Effect.succeed(path.endsWith(".httpapi-codegen.json")),
+          makeDirectory: () => Effect.void,
+          readFileString: () => Effect.succeed('["old.ts", "session.ts"]'),
+          remove: (path) => {
+            removed.push(path)
+            return Effect.void
+          },
+          writeFileString: () => Effect.void,
+        }),
+      ),
+      Effect.tap(() => Effect.sync(() => expect(removed).toEqual(["/generated/old.ts"]))),
+    )
+  })
+
+  it.effect("rejects unsafe and duplicate output paths before writing", () => {
+    const writes: Array<string> = []
+    return Effect.gen(function* () {
+      const error = yield* write(
+        {
+          operations: [],
+          files: [
+            { path: "../outside.ts", content: "" },
+            { path: "client.ts", content: "" },
+            { path: "CLIENT.ts", content: "" },
+          ],
+        },
+        "/generated",
+      ).pipe(Effect.flip)
+
+      expect(error._tag).toBe("GenerationError")
+      expect(writes).toEqual([])
+    }).pipe(
+      Effect.provideService(
+        FileSystem.FileSystem,
+        FileSystem.makeNoop({
+          writeFileString: (path) => {
+            writes.push(path)
+            return Effect.void
+          },
+        }),
+      ),
+    )
+  })
+
+  it.effect("rejects case-insensitive duplicate output paths", () => {
+    const writes: Array<string> = []
+    return Effect.gen(function* () {
+      const error = yield* write(
+        {
+          operations: [],
+          files: [
+            { path: "client.ts", content: "" },
+            { path: "CLIENT.ts", content: "" },
+          ],
+        },
+        "/generated",
+      ).pipe(Effect.flip)
+
+      expect(error._tag).toBe("GenerationError")
+      expect(error.reason).toBe("Duplicate output path: CLIENT.ts")
+      expect(writes).toEqual([])
+    }).pipe(
+      Effect.provideService(
+        FileSystem.FileSystem,
+        FileSystem.makeNoop({
+          writeFileString: (path) => {
+            writes.push(path)
+            return Effect.void
+          },
+        }),
+      ),
+    )
+  })
+
+  it.effect("reserves the private manifest path", () =>
+    write({ operations: [], files: [{ path: ".httpapi-codegen.json", content: "" }] }, "/generated").pipe(
+      Effect.flip,
+      Effect.tap((error) => Effect.sync(() => expect(error.reason).toContain("Unsafe output path"))),
+      Effect.provideService(FileSystem.FileSystem, FileSystem.makeNoop({})),
+    ),
+  )
+
+  it.effect("rejects existing symbolic-link output targets", () =>
+    write({ operations: [], files: [{ path: "session.ts", content: "" }] }, "/generated").pipe(
+      Effect.flip,
+      Effect.tap((error) => Effect.sync(() => expect(error.reason).toBe("Unsafe output path: session.ts"))),
+      Effect.provideService(
+        FileSystem.FileSystem,
+        FileSystem.makeNoop({
+          exists: (path) => Effect.succeed(path.endsWith("session.ts")),
+          makeDirectory: () => Effect.void,
+          stat: () =>
+            Effect.succeed({
+              type: "SymbolicLink",
+              mtime: Option.none(),
+              atime: Option.none(),
+              birthtime: Option.none(),
+              dev: 0,
+              ino: Option.none(),
+              mode: 0,
+              nlink: Option.none(),
+              uid: Option.none(),
+              gid: Option.none(),
+              rdev: Option.none(),
+              size: FileSystem.Size(0),
+              blksize: Option.none(),
+              blocks: Option.none(),
+            }),
+        }),
+      ),
+    ),
+  )
+})

packages/httpapi-codegen/tsconfig.json

@@ -0,0 +1,8 @@
+{
+  "$schema": "https://json.schemastore.org/tsconfig",
+  "extends": "@tsconfig/bun/tsconfig.json",
+  "compilerOptions": {
+    "lib": ["ESNext", "DOM", "DOM.Iterable"],
+    "noUncheckedIndexedAccess": false
+  }
+}

packages/opencode/src/server/routes/instance/httpapi/server.ts

@@ -54,6 +54,7 @@ import { Database } from "@opencode-ai/core/database/database"
 import { LayerNode } from "@opencode-ai/core/effect/layer-node"
 import { httpClient } from "@opencode-ai/core/effect/layer-node-platform"
 import { EventV2 } from "@opencode-ai/core/event"
+import { ApplicationTools } from "@opencode-ai/core/tool/application-tools"
 import { ModelsDev } from "@opencode-ai/core/models-dev"
 import { Npm } from "@opencode-ai/core/npm"
 import { ProjectV2 } from "@opencode-ai/core/project"
@@ -280,6 +281,7 @@ export function createRoutes(
       HttpServer.layerServices,
     ]),
     Layer.provide(LayerNode.buildLayer(app)),
+    Layer.provide(ApplicationTools.layer),
     Layer.provide(Layer.succeed(CorsConfig)(corsOptions)),
     Layer.provideMerge(Observability.layer),
   )

packages/opencode/src/session/prompt.ts

@@ -1086,12 +1086,12 @@ export const layer = Layer.effect(
           }
           if (part.type === "file") {
             result.files.push(
-              new FileAttachment({
+              FileAttachment.make({
                 uri: part.url,
                 mime: part.mime,
                 name: part.filename,
                 source: part.source
-                  ? new Source({
+                  ? Source.make({
                       start: part.source.text.start,
                       end: part.source.text.end,
                       text: part.source.text.value,
@@ -1102,10 +1102,10 @@ export const layer = Layer.effect(
           }
           if (part.type === "agent") {
             result.agents.push(
-              new AgentAttachment({
+              AgentAttachment.make({
                 name: part.name,
                 source: part.source
-                  ? new Source({
+                  ? Source.make({
                       start: part.source.start,
                       end: part.source.end,
                       text: part.source.value,
@@ -1130,7 +1130,7 @@ export const layer = Layer.effect(
           messageID: SessionMessage.ID.create(),
           timestamp: DateTime.makeUnsafe(info.time.created),
           delivery: "steer",
-          prompt: new Prompt({
+          prompt: Prompt.make({
             text: nextPrompt.text.join("\n"),
             files: nextPrompt.files,
             agents: nextPrompt.agents,

packages/opencode/test/server/httpapi-public-openapi.test.ts

@@ -16,6 +16,7 @@ type OpenApiResponse = {
   readonly content?: Record<string, { readonly schema?: OpenApiSchema }>
 }
 type OpenApiOperation = {
+  readonly operationId?: string
   readonly parameters?: ReadonlyArray<{
     readonly name: string
     readonly in: string
@@ -68,6 +69,18 @@ function isBuiltInEndpointError(name: string) {
 }
 
 describe("PublicApi OpenAPI v2 errors", () => {
+  test("keeps current and v2 session groups distinct", () => {
+    const spec = OpenApi.fromApi(PublicApi) as OpenApiSpec
+
+    expect(spec.paths["/session"]?.get?.operationId).toBe("session.list")
+    expect(spec.paths["/session/{sessionID}"]?.get?.operationId).toBe("session.get")
+    expect(spec.paths["/api/session"]?.get?.operationId).toBe("v2.session.list")
+    expect(spec.paths["/api/session/{sessionID}"]?.get?.operationId).toBe("v2.session.get")
+    expect(responseRef(spec.paths["/api/session"]?.get?.responses?.["200"])).toBe(
+      "#/components/schemas/SessionsResponse",
+    )
+  })
+
   test("documents nested legacy global sync events", () => {
     const spec = OpenApi.fromApi(PublicApi) as OpenApiSpec
     const schema = spec.components.schemas.SyncEventSessionCreated

packages/opencode/test/server/httpapi-session.test.ts

@@ -23,7 +23,6 @@ import * as HttpSessionError from "../../src/server/routes/instance/httpapi/hand
 import { SessionPaths } from "../../src/server/routes/instance/httpapi/groups/session"
 import { Session } from "@/session/session"
 import { MessageID, PartID, SessionID, type SessionID as SessionIDType } from "../../src/session/schema"
-import { MessageV2 } from "../../src/session/message-v2"
 import { Database } from "@opencode-ai/core/database/database"
 import { SessionInputTable, SessionMessageTable, SessionTable } from "@opencode-ai/core/session/sql"
 import { SessionMessage } from "@opencode-ai/core/session/message"
@@ -129,7 +128,7 @@ const createLocalWorkspace = (input: { projectID: Project.Info["id"]; type: stri
 
 const insertLegacyAssistantMessage = (sessionID: SessionIDType, seq = 1, time = seq) =>
   Effect.gen(function* () {
-    const message = new SessionMessage.Assistant({
+    const message = SessionMessage.Assistant.make({
       id: SessionMessage.ID.create(),
       type: "assistant",
       agent: "build",

packages/protocol/package.json

@@ -0,0 +1,25 @@
+{
+  "$schema": "https://json.schemastore.org/package.json",
+  "name": "@opencode-ai/protocol",
+  "private": true,
+  "type": "module",
+  "license": "MIT",
+  "exports": {
+    "./errors": "./src/errors.ts",
+    "./session": "./src/session.ts",
+    "./session-cursor": "./src/session-cursor.ts",
+    "./middleware/session-location": "./src/middleware/session-location.ts"
+  },
+  "scripts": {
+    "typecheck": "tsgo --noEmit"
+  },
+  "dependencies": {
+    "@opencode-ai/schema": "workspace:*",
+    "effect": "catalog:"
+  },
+  "devDependencies": {
+    "@tsconfig/bun": "catalog:",
+    "@types/bun": "catalog:",
+    "@typescript/native-preview": "catalog:"
+  }
+}

packages/protocol/src/errors.ts

@@ -0,0 +1,77 @@
+import { Schema } from "effect"
+
+export class InvalidRequestError extends Schema.TaggedErrorClass<InvalidRequestError>()(
+  "InvalidRequestError",
+  {
+    message: Schema.String,
+    kind: Schema.optional(Schema.String),
+    field: Schema.optional(Schema.String),
+  },
+  { httpApiStatus: 400 },
+) {}
+
+export class UnauthorizedError extends Schema.TaggedErrorClass<UnauthorizedError>()(
+  "UnauthorizedError",
+  { message: Schema.String },
+  { httpApiStatus: 401 },
+) {}
+
+export class ConflictError extends Schema.TaggedErrorClass<ConflictError>()(
+  "ConflictError",
+  { message: Schema.String, resource: Schema.optional(Schema.String) },
+  { httpApiStatus: 409 },
+) {}
+
+export class ServiceUnavailableError extends Schema.TaggedErrorClass<ServiceUnavailableError>()(
+  "ServiceUnavailableError",
+  { message: Schema.String, service: Schema.optional(Schema.String) },
+  { httpApiStatus: 503 },
+) {}
+
+export class UnknownError extends Schema.TaggedErrorClass<UnknownError>()(
+  "UnknownError",
+  { message: Schema.String, ref: Schema.optional(Schema.String) },
+  { httpApiStatus: 500 },
+) {}
+
+export class ProviderNotFoundError extends Schema.TaggedErrorClass<ProviderNotFoundError>()(
+  "ProviderNotFoundError",
+  { providerID: Schema.String, message: Schema.String },
+  { httpApiStatus: 404 },
+) {}
+
+export class SessionNotFoundError extends Schema.TaggedErrorClass<SessionNotFoundError>()(
+  "SessionNotFoundError",
+  { sessionID: Schema.String, message: Schema.String },
+  { httpApiStatus: 404 },
+) {}
+
+export class InvalidCursorError extends Schema.TaggedErrorClass<InvalidCursorError>()(
+  "InvalidCursorError",
+  { message: Schema.String },
+  { httpApiStatus: 400 },
+) {}
+
+export class PermissionNotFoundError extends Schema.TaggedErrorClass<PermissionNotFoundError>()(
+  "PermissionNotFoundError",
+  { requestID: Schema.String, message: Schema.String },
+  { httpApiStatus: 404 },
+) {}
+
+export class QuestionNotFoundError extends Schema.TaggedErrorClass<QuestionNotFoundError>()(
+  "QuestionNotFoundError",
+  { requestID: Schema.String, message: Schema.String },
+  { httpApiStatus: 404 },
+) {}
+
+export class ForbiddenError extends Schema.TaggedErrorClass<ForbiddenError>()(
+  "ForbiddenError",
+  { message: Schema.String },
+  { httpApiStatus: 403 },
+) {}
+
+export class PtyNotFoundError extends Schema.TaggedErrorClass<PtyNotFoundError>()(
+  "PtyNotFoundError",
+  { ptyID: Schema.String, message: Schema.String },
+  { httpApiStatus: 404 },
+) {}

packages/protocol/src/middleware/session-location.ts

@@ -0,0 +1,7 @@
+import { HttpApiMiddleware } from "effect/unstable/httpapi"
+import { InvalidRequestError, SessionNotFoundError } from "../errors"
+
+export class SessionLocationMiddleware extends HttpApiMiddleware.Service<SessionLocationMiddleware>()(
+  "@opencode/HttpApiSessionLocation",
+  { error: [InvalidRequestError, SessionNotFoundError] },
+) {}

packages/protocol/src/session-cursor.ts

@@ -0,0 +1,30 @@
+import { AbsolutePath, PositiveInt, RelativePath } from "@opencode-ai/schema/schema"
+import { Project } from "@opencode-ai/schema/project"
+import { Session } from "@opencode-ai/schema/session"
+import { Workspace } from "@opencode-ai/schema/workspace"
+import { Effect, Encoding, Schema, Struct } from "effect"
+
+const fields = {
+  workspace: Workspace.ID.pipe(Schema.optional),
+  limit: Schema.NumberFromString.pipe(Schema.decodeTo(PositiveInt), Schema.optional),
+  order: Schema.Literals(["asc", "desc"]).pipe(Schema.optional),
+  search: Schema.String.pipe(Schema.optional),
+}
+const withCursor = <Fields extends Schema.Struct.Fields>(schema: Schema.Struct<Fields>) =>
+  schema.mapFields((value) => ({ ...Struct.omit(value, ["limit"]), anchor: Session.ListAnchor }))
+const input = Schema.Union([
+  withCursor(Schema.Struct({ ...fields, directory: AbsolutePath })),
+  withCursor(Schema.Struct({ ...fields, project: Project.ID, subpath: RelativePath.pipe(Schema.optional) })),
+  withCursor(Schema.Struct(fields)),
+])
+const json = Schema.fromJsonString(input)
+const encode = Schema.encodeSync(json)
+const decode = Schema.decodeUnknownEffect(json)
+
+const schema = Schema.String.pipe(Schema.brand("SessionsCursor"))
+const make = Schema.decodeUnknownSync(schema)
+export const SessionsCursor = Object.assign(schema, {
+  make: (value: typeof input.Type) => make(Encoding.encodeBase64Url(encode(value))),
+  parse: (value: string) => Effect.fromResult(Encoding.decodeBase64UrlString(value)).pipe(Effect.flatMap(decode)),
+})
+export type SessionsCursor = typeof SessionsCursor.Type

packages/protocol/src/session.ts

@@ -0,0 +1,194 @@
+import { Agent } from "@opencode-ai/schema/agent"
+import { Location } from "@opencode-ai/schema/location"
+import { Model } from "@opencode-ai/schema/model"
+import { Project } from "@opencode-ai/schema/project"
+import { AbsolutePath, PositiveInt, RelativePath } from "@opencode-ai/schema/schema"
+import { Session } from "@opencode-ai/schema/session"
+import { SessionInput } from "@opencode-ai/schema/session-input"
+import { SessionMessage } from "@opencode-ai/schema/session-message"
+import { Prompt } from "@opencode-ai/schema/prompt"
+import { Workspace } from "@opencode-ai/schema/workspace"
+import { Schema } from "effect"
+import { HttpApiEndpoint, HttpApiGroup, HttpApiSchema, OpenApi } from "effect/unstable/httpapi"
+import {
+  ConflictError,
+  InvalidCursorError,
+  InvalidRequestError,
+  ServiceUnavailableError,
+  SessionNotFoundError,
+  UnauthorizedError,
+  UnknownError,
+} from "./errors"
+import { SessionLocationMiddleware } from "./middleware/session-location"
+import { SessionsCursor } from "./session-cursor"
+
+export { SessionsCursor } from "./session-cursor"
+
+export const SessionsQuery = Schema.Struct({
+  workspace: Workspace.ID.pipe(Schema.optional),
+  limit: Schema.NumberFromString.pipe(Schema.decodeTo(PositiveInt), Schema.optional).annotate({
+    description: "Maximum number of sessions to return. Defaults to the newest 50 sessions.",
+  }),
+  order: Schema.Literals(["asc", "desc"]).pipe(Schema.optional).annotate({
+    description: "Session order for the first page. Use desc for newest first or asc for oldest first.",
+  }),
+  search: Schema.String.pipe(Schema.optional),
+  directory: AbsolutePath.pipe(Schema.optional),
+  project: Project.ID.pipe(Schema.optional),
+  subpath: RelativePath.pipe(Schema.optional),
+  cursor: SessionsCursor.pipe(Schema.optional),
+}).annotate({ identifier: "SessionsQuery" })
+
+export const SessionGroup = HttpApiGroup.make("server.session")
+  .add(
+    HttpApiEndpoint.get("session.list", "/api/session", {
+      query: SessionsQuery,
+      success: Schema.Struct({
+        data: Schema.Array(Session.Info),
+        cursor: Schema.Struct({
+          previous: SessionsCursor.pipe(Schema.optional),
+          next: SessionsCursor.pipe(Schema.optional),
+        }),
+      }).annotate({ identifier: "SessionsResponse" }),
+      error: [InvalidCursorError, InvalidRequestError, UnauthorizedError],
+    }).annotateMerge(
+      OpenApi.annotations({
+        identifier: "v2.session.list",
+        summary: "List sessions",
+        description:
+          "Retrieve sessions in the requested order. Items keep that order across pages; use cursor.next or cursor.previous to move through the ordered list.",
+      }),
+    ),
+  )
+  .add(
+    HttpApiEndpoint.post("session.create", "/api/session", {
+      payload: Schema.Struct({
+        id: Session.ID.pipe(Schema.optional),
+        agent: Agent.ID.pipe(Schema.optional),
+        model: Model.Ref.pipe(Schema.optional),
+        location: Location.Ref.pipe(Schema.optional),
+      }),
+      success: Schema.Struct({ data: Session.Info }),
+      error: [InvalidRequestError, UnauthorizedError],
+    }).annotateMerge(
+      OpenApi.annotations({
+        identifier: "v2.session.create",
+        summary: "Create session",
+        description: "Create a session at the requested location.",
+      }),
+    ),
+  )
+  .add(
+    HttpApiEndpoint.get("session.get", "/api/session/:sessionID", {
+      params: { sessionID: Session.ID },
+      success: Schema.Struct({ data: Session.Info }),
+      error: [InvalidRequestError, SessionNotFoundError, UnauthorizedError],
+    })
+      .middleware(SessionLocationMiddleware)
+      .annotateMerge(
+        OpenApi.annotations({
+          identifier: "v2.session.get",
+          summary: "Get session",
+          description: "Retrieve a session by ID.",
+        }),
+      ),
+  )
+  .add(
+    HttpApiEndpoint.post("session.switchAgent", "/api/session/:sessionID/agent", {
+      params: { sessionID: Session.ID },
+      payload: Schema.Struct({ agent: Agent.ID }),
+      success: HttpApiSchema.NoContent,
+      error: [InvalidRequestError, SessionNotFoundError, UnauthorizedError],
+    })
+      .middleware(SessionLocationMiddleware)
+      .annotateMerge(
+        OpenApi.annotations({
+          identifier: "v2.session.switchAgent",
+          summary: "Switch session agent",
+          description: "Switch the agent used by subsequent provider turns.",
+        }),
+      ),
+  )
+  .add(
+    HttpApiEndpoint.post("session.switchModel", "/api/session/:sessionID/model", {
+      params: { sessionID: Session.ID },
+      payload: Schema.Struct({ model: Model.Ref }),
+      success: HttpApiSchema.NoContent,
+      error: [InvalidRequestError, SessionNotFoundError, UnauthorizedError],
+    })
+      .middleware(SessionLocationMiddleware)
+      .annotateMerge(
+        OpenApi.annotations({
+          identifier: "v2.session.switchModel",
+          summary: "Switch session model",
+          description: "Switch the model used by subsequent provider turns.",
+        }),
+      ),
+  )
+  .add(
+    HttpApiEndpoint.post("session.prompt", "/api/session/:sessionID/prompt", {
+      params: { sessionID: Session.ID },
+      payload: Schema.Struct({
+        id: SessionMessage.ID.pipe(Schema.optional),
+        prompt: Prompt,
+        delivery: SessionInput.Delivery.pipe(Schema.optional),
+        resume: Schema.Boolean.pipe(Schema.optional),
+      }),
+      success: Schema.Struct({ data: SessionInput.Admitted }),
+      error: [ConflictError, InvalidRequestError, SessionNotFoundError, UnauthorizedError],
+    })
+      .middleware(SessionLocationMiddleware)
+      .annotateMerge(
+        OpenApi.annotations({
+          identifier: "v2.session.prompt",
+          summary: "Send message",
+          description: "Durably admit one session input and schedule agent-loop execution unless resume is false.",
+        }),
+      ),
+  )
+  .add(
+    HttpApiEndpoint.post("session.compact", "/api/session/:sessionID/compact", {
+      params: { sessionID: Session.ID },
+      success: HttpApiSchema.NoContent,
+      error: [SessionNotFoundError, ServiceUnavailableError, UnauthorizedError],
+    })
+      .middleware(SessionLocationMiddleware)
+      .annotateMerge(
+        OpenApi.annotations({
+          identifier: "v2.session.compact",
+          summary: "Compact session",
+          description: "Compact a session conversation.",
+        }),
+      ),
+  )
+  .add(
+    HttpApiEndpoint.post("session.wait", "/api/session/:sessionID/wait", {
+      params: { sessionID: Session.ID },
+      success: HttpApiSchema.NoContent,
+      error: [SessionNotFoundError, ServiceUnavailableError, UnauthorizedError],
+    })
+      .middleware(SessionLocationMiddleware)
+      .annotateMerge(
+        OpenApi.annotations({
+          identifier: "v2.session.wait",
+          summary: "Wait for session",
+          description: "Wait for a session agent loop to become idle.",
+        }),
+      ),
+  )
+  .add(
+    HttpApiEndpoint.get("session.context", "/api/session/:sessionID/context", {
+      params: { sessionID: Session.ID },
+      success: Schema.Struct({ data: Schema.Array(SessionMessage.Message) }),
+      error: [SessionNotFoundError, UnauthorizedError, UnknownError],
+    })
+      .middleware(SessionLocationMiddleware)
+      .annotateMerge(
+        OpenApi.annotations({
+          identifier: "v2.session.context",
+          summary: "Get session context",
+          description: "Retrieve the active context messages for a session (all messages after the last compaction).",
+        }),
+      ),
+  )
+  .annotateMerge(OpenApi.annotations({ title: "sessions", description: "Experimental session routes." }))

packages/protocol/tsconfig.json

@@ -0,0 +1,8 @@
+{
+  "$schema": "https://json.schemastore.org/tsconfig",
+  "extends": "@tsconfig/bun/tsconfig.json",
+  "compilerOptions": {
+    "lib": ["ESNext", "DOM", "DOM.Iterable"],
+    "noUncheckedIndexedAccess": false
+  }
+}

packages/schema/package.json

@@ -0,0 +1,23 @@
+{
+  "$schema": "https://json.schemastore.org/package.json",
+  "name": "@opencode-ai/schema",
+  "private": true,
+  "type": "module",
+  "license": "MIT",
+  "exports": {
+    ".": "./src/index.ts",
+    "./*": "./src/*.ts"
+  },
+  "scripts": {
+    "typecheck": "tsgo --noEmit"
+  },
+  "dependencies": {
+    "@noble/hashes": "catalog:",
+    "effect": "catalog:"
+  },
+  "devDependencies": {
+    "@tsconfig/bun": "catalog:",
+    "@types/bun": "catalog:",
+    "@typescript/native-preview": "catalog:"
+  }
+}

packages/schema/src/agent.ts

@@ -0,0 +1,6 @@
+export * as Agent from "./agent"
+
+import { Schema } from "effect"
+
+export const ID = Schema.String.pipe(Schema.brand("AgentV2.ID"))
+export type ID = typeof ID.Type

packages/schema/src/identifier.ts

@@ -0,0 +1,31 @@
+const length = 26
+const chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+let lastTimestamp = 0
+let counter = 0
+
+export function ascending() {
+  return create(false)
+}
+
+export function descending() {
+  return create(true)
+}
+
+function create(descending: boolean) {
+  const timestamp = Date.now()
+  if (timestamp !== lastTimestamp) {
+    lastTimestamp = timestamp
+    counter = 0
+  }
+  counter++
+
+  const current = BigInt(timestamp) * 0x1000n + BigInt(counter)
+  const value = descending ? ~current : current
+  const time = Array.from({ length: 6 }, (_, index) =>
+    Number((value >> BigInt(40 - 8 * index)) & 0xffn)
+      .toString(16)
+      .padStart(2, "0"),
+  ).join("")
+  const bytes = crypto.getRandomValues(new Uint8Array(length - 12))
+  return time + Array.from(bytes, (byte) => chars[byte % 62]).join("")
+}

packages/schema/src/index.ts

@@ -0,0 +1,11 @@
+export { Agent } from "./agent"
+export { Location } from "./location"
+export { Model } from "./model"
+export { Project } from "./project"
+export { Provider } from "./provider"
+export { Session } from "./session"
+export { SessionInput } from "./session-input"
+export { SessionMessage } from "./session-message"
+export { Workspace } from "./workspace"
+export { Prompt, Source, FileAttachment, AgentAttachment } from "./prompt"
+export * from "./schema"

packages/schema/src/location.ts

@@ -0,0 +1,11 @@
+export * as Location from "./location"
+
+import { Effect, Schema } from "effect"
+import { AbsolutePath } from "./schema"
+import { Workspace } from "./workspace"
+
+export interface Ref extends Schema.Schema.Type<typeof Ref> {}
+export const Ref = Schema.Struct({
+  directory: AbsolutePath,
+  workspaceID: Schema.optional(Workspace.ID).pipe(Schema.withConstructorDefault(Effect.succeed(undefined))),
+}).annotate({ identifier: "Location.Ref" })

packages/schema/src/model.ts

@@ -0,0 +1,17 @@
+export * as Model from "./model"
+
+import { Schema } from "effect"
+import { Provider } from "./provider"
+
+export const ID = Schema.String.pipe(Schema.brand("ModelV2.ID"))
+export type ID = typeof ID.Type
+
+export const VariantID = Schema.String.pipe(Schema.brand("VariantID"))
+export type VariantID = typeof VariantID.Type
+
+export const Ref = Schema.Struct({
+  id: ID,
+  providerID: Provider.ID,
+  variant: VariantID.pipe(Schema.optional),
+})
+export type Ref = typeof Ref.Type

packages/schema/src/project.ts

@@ -0,0 +1,10 @@
+export * as Project from "./project"
+
+import { Schema } from "effect"
+import { withStatics } from "./schema"
+
+export const ID = Schema.String.pipe(
+  Schema.brand("Project.ID"),
+  withStatics((schema) => ({ global: schema.make("global") })),
+)
+export type ID = typeof ID.Type

packages/schema/src/prompt.ts

@@ -0,0 +1,30 @@
+import { Schema } from "effect"
+
+export interface Source extends Schema.Schema.Type<typeof Source> {}
+export const Source = Schema.Struct({
+  start: Schema.Finite,
+  end: Schema.Finite,
+  text: Schema.String,
+}).annotate({ identifier: "Prompt.Source" })
+
+export interface FileAttachment extends Schema.Schema.Type<typeof FileAttachment> {}
+export const FileAttachment = Schema.Struct({
+  uri: Schema.String,
+  mime: Schema.String,
+  name: Schema.String.pipe(Schema.optional),
+  description: Schema.String.pipe(Schema.optional),
+  source: Source.pipe(Schema.optional),
+}).annotate({ identifier: "Prompt.FileAttachment" })
+
+export interface AgentAttachment extends Schema.Schema.Type<typeof AgentAttachment> {}
+export const AgentAttachment = Schema.Struct({
+  name: Schema.String,
+  source: Source.pipe(Schema.optional),
+}).annotate({ identifier: "Prompt.AgentAttachment" })
+
+export interface Prompt extends Schema.Schema.Type<typeof Prompt> {}
+export const Prompt = Schema.Struct({
+  text: Schema.String,
+  files: Schema.Array(FileAttachment).pipe(Schema.optional),
+  agents: Schema.Array(AgentAttachment).pipe(Schema.optional),
+}).annotate({ identifier: "Prompt" })

packages/schema/src/provider.ts

@@ -0,0 +1,22 @@
+export * as Provider from "./provider"
+
+import { Schema } from "effect"
+import { withStatics } from "./schema"
+
+export const ID = Schema.String.pipe(
+  Schema.brand("ProviderV2.ID"),
+  withStatics((schema) => ({
+    opencode: schema.make("opencode"),
+    anthropic: schema.make("anthropic"),
+    openai: schema.make("openai"),
+    google: schema.make("google"),
+    googleVertex: schema.make("google-vertex"),
+    githubCopilot: schema.make("github-copilot"),
+    amazonBedrock: schema.make("amazon-bedrock"),
+    azure: schema.make("azure"),
+    openrouter: schema.make("openrouter"),
+    mistral: schema.make("mistral"),
+    gitlab: schema.make("gitlab"),
+  })),
+)
+export type ID = typeof ID.Type

packages/schema/src/schema.ts

@@ -0,0 +1,40 @@
+import { DateTime, Option, Schema, SchemaGetter } from "effect"
+import { sha256 } from "@noble/hashes/sha2.js"
+import { bytesToHex } from "@noble/hashes/utils.js"
+
+export const PositiveInt = Schema.Int.check(Schema.isGreaterThan(0))
+export const NonNegativeInt = Schema.Int.check(Schema.isGreaterThanOrEqualTo(0))
+
+export const RelativePath = Schema.String.pipe(Schema.brand("RelativePath"))
+export type RelativePath = typeof RelativePath.Type
+
+export const AbsolutePath = Schema.String.pipe(Schema.brand("AbsolutePath"))
+export type AbsolutePath = typeof AbsolutePath.Type
+
+export const optionalOmitUndefined = <S extends Schema.Top>(schema: S) =>
+  Schema.optionalKey(schema).pipe(
+    Schema.decodeTo(Schema.optional(schema), {
+      decode: SchemaGetter.passthrough({ strict: false }),
+      encode: SchemaGetter.transformOptional(Option.filter((value) => value !== undefined)),
+    }),
+  )
+
+export const withStatics =
+  <S extends object, M extends Record<string, unknown>>(methods: (schema: S) => M) =>
+  (schema: S): S & M =>
+    Object.assign(schema, methods(schema))
+
+export interface ExternalID {
+  readonly namespace: string
+  readonly key: string
+}
+
+export const externalID = (prefix: string, input: ExternalID) =>
+  `${prefix}_${bytesToHex(sha256(new TextEncoder().encode(JSON.stringify([input.namespace, input.key]))))}`
+
+export const DateTimeUtcFromMillis = Schema.Finite.pipe(
+  Schema.decodeTo(Schema.DateTimeUtc, {
+    decode: SchemaGetter.transform((value) => DateTime.makeUnsafe(value)),
+    encode: SchemaGetter.transform((value) => DateTime.toEpochMillis(value)),
+  }),
+)

packages/schema/src/session-input.ts

@@ -0,0 +1,21 @@
+export * as SessionInput from "./session-input"
+
+import { Schema } from "effect"
+import { Prompt } from "./prompt"
+import { DateTimeUtcFromMillis, NonNegativeInt } from "./schema"
+import { Session } from "./session"
+import { SessionMessage } from "./session-message"
+
+export const Delivery = Schema.Literals(["steer", "queue"])
+export type Delivery = typeof Delivery.Type
+
+export interface Admitted extends Schema.Schema.Type<typeof Admitted> {}
+export const Admitted = Schema.Struct({
+  admittedSeq: NonNegativeInt,
+  id: SessionMessage.ID,
+  sessionID: Session.ID,
+  prompt: Prompt,
+  delivery: Delivery,
+  timeCreated: DateTimeUtcFromMillis,
+  promotedSeq: NonNegativeInt.pipe(Schema.optional),
+}).annotate({ identifier: "SessionInput.Admitted" })

packages/schema/src/session-message.ts

@@ -0,0 +1,218 @@
+export * as SessionMessage from "./session-message"
+
+import { Schema } from "effect"
+import { Model } from "./model"
+import { FileAttachment, Prompt } from "./prompt"
+import { DateTimeUtcFromMillis, withStatics } from "./schema"
+import { Session } from "./session"
+import { ascending } from "./identifier"
+
+export const ID = Schema.String.check(Schema.isStartsWith("msg_")).pipe(
+  Schema.brand("Session.Message.ID"),
+  withStatics((schema) => ({ create: () => schema.make("msg_" + ascending()) })),
+)
+export type ID = typeof ID.Type
+
+const ProviderMetadata = Schema.Record(Schema.String, Schema.Record(Schema.String, Schema.Unknown))
+const ToolContent = Schema.Union([
+  Schema.Struct({ type: Schema.Literal("text"), text: Schema.String }).annotate({
+    identifier: "Tool.TextContent",
+  }),
+  Schema.Struct({
+    type: Schema.Literal("file"),
+    uri: Schema.String,
+    mime: Schema.String,
+    name: Schema.optional(Schema.String),
+  }).annotate({ identifier: "Tool.FileContent" }),
+]).pipe(Schema.toTaggedUnion("type"))
+const UnknownError = Schema.Struct({
+  type: Schema.Literal("unknown"),
+  message: Schema.String,
+}).annotate({ identifier: "Session.Error.Unknown" })
+
+const Base = {
+  id: ID,
+  metadata: Schema.Record(Schema.String, Schema.Unknown).pipe(Schema.optional),
+  time: Schema.Struct({ created: DateTimeUtcFromMillis }),
+}
+
+export interface AgentSwitched extends Schema.Schema.Type<typeof AgentSwitched> {}
+export const AgentSwitched = Schema.Struct({
+  ...Base,
+  type: Schema.Literal("agent-switched"),
+  agent: Schema.String,
+}).annotate({ identifier: "Session.Message.AgentSwitched" })
+
+export interface ModelSwitched extends Schema.Schema.Type<typeof ModelSwitched> {}
+export const ModelSwitched = Schema.Struct({
+  ...Base,
+  type: Schema.Literal("model-switched"),
+  model: Model.Ref,
+}).annotate({ identifier: "Session.Message.ModelSwitched" })
+
+export interface User extends Schema.Schema.Type<typeof User> {}
+export const User = Schema.Struct({
+  ...Base,
+  text: Prompt.fields.text,
+  files: Prompt.fields.files,
+  agents: Prompt.fields.agents,
+  type: Schema.Literal("user"),
+  time: Schema.Struct({ created: DateTimeUtcFromMillis }),
+}).annotate({ identifier: "Session.Message.User" })
+
+export interface Synthetic extends Schema.Schema.Type<typeof Synthetic> {}
+export const Synthetic = Schema.Struct({
+  ...Base,
+  sessionID: Session.ID,
+  text: Schema.String,
+  type: Schema.Literal("synthetic"),
+}).annotate({ identifier: "Session.Message.Synthetic" })
+
+export interface System extends Schema.Schema.Type<typeof System> {}
+export const System = Schema.Struct({
+  ...Base,
+  type: Schema.Literal("system"),
+  text: Schema.String,
+}).annotate({ identifier: "Session.Message.System" })
+
+export interface Shell extends Schema.Schema.Type<typeof Shell> {}
+export const Shell = Schema.Struct({
+  ...Base,
+  type: Schema.Literal("shell"),
+  callID: Schema.String,
+  command: Schema.String,
+  output: Schema.String,
+  time: Schema.Struct({
+    created: DateTimeUtcFromMillis,
+    completed: DateTimeUtcFromMillis.pipe(Schema.optional),
+  }),
+}).annotate({ identifier: "Session.Message.Shell" })
+
+export interface ToolStatePending extends Schema.Schema.Type<typeof ToolStatePending> {}
+export const ToolStatePending = Schema.Struct({
+  status: Schema.Literal("pending"),
+  input: Schema.String,
+}).annotate({ identifier: "Session.Message.ToolState.Pending" })
+
+export interface ToolStateRunning extends Schema.Schema.Type<typeof ToolStateRunning> {}
+export const ToolStateRunning = Schema.Struct({
+  status: Schema.Literal("running"),
+  input: Schema.Record(Schema.String, Schema.Unknown),
+  structured: Schema.Record(Schema.String, Schema.Any),
+  content: ToolContent.pipe(Schema.Array),
+}).annotate({ identifier: "Session.Message.ToolState.Running" })
+
+export interface ToolStateCompleted extends Schema.Schema.Type<typeof ToolStateCompleted> {}
+export const ToolStateCompleted = Schema.Struct({
+  status: Schema.Literal("completed"),
+  input: Schema.Record(Schema.String, Schema.Unknown),
+  attachments: FileAttachment.pipe(Schema.Array, Schema.optional),
+  content: ToolContent.pipe(Schema.Array),
+  outputPaths: Schema.Array(Schema.String).pipe(Schema.optional),
+  structured: Schema.Record(Schema.String, Schema.Any),
+  result: Schema.Unknown.pipe(Schema.optional),
+}).annotate({ identifier: "Session.Message.ToolState.Completed" })
+
+export interface ToolStateError extends Schema.Schema.Type<typeof ToolStateError> {}
+export const ToolStateError = Schema.Struct({
+  status: Schema.Literal("error"),
+  input: Schema.Record(Schema.String, Schema.Unknown),
+  content: ToolContent.pipe(Schema.Array),
+  structured: Schema.Record(Schema.String, Schema.Any),
+  error: UnknownError,
+  result: Schema.Unknown.pipe(Schema.optional),
+}).annotate({ identifier: "Session.Message.ToolState.Error" })
+
+export const ToolState = Schema.Union([ToolStatePending, ToolStateRunning, ToolStateCompleted, ToolStateError]).pipe(
+  Schema.toTaggedUnion("status"),
+)
+export type ToolState = ToolStatePending | ToolStateRunning | ToolStateCompleted | ToolStateError
+
+export interface AssistantTool extends Schema.Schema.Type<typeof AssistantTool> {}
+export const AssistantTool = Schema.Struct({
+  type: Schema.Literal("tool"),
+  id: Schema.String,
+  name: Schema.String,
+  provider: Schema.Struct({
+    executed: Schema.Boolean,
+    metadata: ProviderMetadata.pipe(Schema.optional),
+    resultMetadata: ProviderMetadata.pipe(Schema.optional),
+  }).pipe(Schema.optional),
+  state: ToolState,
+  time: Schema.Struct({
+    created: DateTimeUtcFromMillis,
+    ran: DateTimeUtcFromMillis.pipe(Schema.optional),
+    completed: DateTimeUtcFromMillis.pipe(Schema.optional),
+    pruned: DateTimeUtcFromMillis.pipe(Schema.optional),
+  }),
+}).annotate({ identifier: "Session.Message.Assistant.Tool" })
+
+export interface AssistantText extends Schema.Schema.Type<typeof AssistantText> {}
+export const AssistantText = Schema.Struct({
+  type: Schema.Literal("text"),
+  id: Schema.String,
+  text: Schema.String,
+}).annotate({ identifier: "Session.Message.Assistant.Text" })
+
+export interface AssistantReasoning extends Schema.Schema.Type<typeof AssistantReasoning> {}
+export const AssistantReasoning = Schema.Struct({
+  type: Schema.Literal("reasoning"),
+  id: Schema.String,
+  text: Schema.String,
+  providerMetadata: ProviderMetadata.pipe(Schema.optional),
+}).annotate({ identifier: "Session.Message.Assistant.Reasoning" })
+
+export const AssistantContent = Schema.Union([AssistantText, AssistantReasoning, AssistantTool]).pipe(
+  Schema.toTaggedUnion("type"),
+)
+export type AssistantContent = AssistantText | AssistantReasoning | AssistantTool
+
+export interface Assistant extends Schema.Schema.Type<typeof Assistant> {}
+export const Assistant = Schema.Struct({
+  ...Base,
+  type: Schema.Literal("assistant"),
+  agent: Schema.String,
+  model: Model.Ref,
+  content: AssistantContent.pipe(Schema.Array),
+  snapshot: Schema.Struct({
+    start: Schema.String.pipe(Schema.optional),
+    end: Schema.String.pipe(Schema.optional),
+  }).pipe(Schema.optional),
+  finish: Schema.String.pipe(Schema.optional),
+  cost: Schema.Finite.pipe(Schema.optional),
+  tokens: Schema.Struct({
+    input: Schema.Finite,
+    output: Schema.Finite,
+    reasoning: Schema.Finite,
+    cache: Schema.Struct({ read: Schema.Finite, write: Schema.Finite }),
+  }).pipe(Schema.optional),
+  error: UnknownError.pipe(Schema.optional),
+  time: Schema.Struct({
+    created: DateTimeUtcFromMillis,
+    completed: DateTimeUtcFromMillis.pipe(Schema.optional),
+  }),
+}).annotate({ identifier: "Session.Message.Assistant" })
+
+export interface Compaction extends Schema.Schema.Type<typeof Compaction> {}
+export const Compaction = Schema.Struct({
+  type: Schema.Literal("compaction"),
+  reason: Schema.Literals(["auto", "manual"]),
+  summary: Schema.String,
+  recent: Schema.String,
+  ...Base,
+}).annotate({ identifier: "Session.Message.Compaction" })
+
+export const Message = Schema.Union([
+  AgentSwitched,
+  ModelSwitched,
+  User,
+  Synthetic,
+  System,
+  Shell,
+  Assistant,
+  Compaction,
+])
+  .pipe(Schema.toTaggedUnion("type"))
+  .annotate({ identifier: "Session.Message" })
+export type Message = AgentSwitched | ModelSwitched | User | Synthetic | System | Shell | Assistant | Compaction
+export type Type = Message["type"]

packages/schema/src/session.ts

@@ -0,0 +1,57 @@
+export * as Session from "./session"
+
+import { Schema } from "effect"
+import { Agent } from "./agent"
+import { Location } from "./location"
+import { Model } from "./model"
+import { Project } from "./project"
+import { DateTimeUtcFromMillis, externalID, type ExternalID, optionalOmitUndefined, RelativePath } from "./schema"
+import { withStatics } from "./schema"
+import { descending } from "./identifier"
+
+export const ID = Schema.String.check(Schema.isStartsWith("ses")).pipe(
+  Schema.brand("SessionID"),
+  withStatics((schema) => {
+    const create = () => schema.make("ses_" + descending())
+    return {
+      create,
+      descending: (id?: string) => (id === undefined ? create() : schema.make(id)),
+      fromExternal: (input: ExternalID) => schema.make(externalID("ses", input)),
+    }
+  }),
+)
+export type ID = typeof ID.Type
+
+export interface Info extends Schema.Schema.Type<typeof Info> {}
+export const Info = Schema.Struct({
+  id: ID,
+  parentID: ID.pipe(optionalOmitUndefined),
+  projectID: Project.ID,
+  agent: Agent.ID.pipe(Schema.optional),
+  model: Model.Ref.pipe(Schema.optional),
+  cost: Schema.Finite,
+  tokens: Schema.Struct({
+    input: Schema.Finite,
+    output: Schema.Finite,
+    reasoning: Schema.Finite,
+    cache: Schema.Struct({
+      read: Schema.Finite,
+      write: Schema.Finite,
+    }),
+  }),
+  time: Schema.Struct({
+    created: DateTimeUtcFromMillis,
+    updated: DateTimeUtcFromMillis,
+    archived: DateTimeUtcFromMillis.pipe(Schema.optional),
+  }),
+  title: Schema.String,
+  location: Location.Ref,
+  subpath: RelativePath.pipe(Schema.optional),
+}).annotate({ identifier: "SessionV2.Info" })
+
+export const ListAnchor = Schema.Struct({
+  id: ID,
+  time: Schema.Finite,
+  direction: Schema.Literals(["previous", "next"]),
+})
+export type ListAnchor = typeof ListAnchor.Type

packages/schema/src/workspace.ts

@@ -0,0 +1,18 @@
+export * as Workspace from "./workspace"
+
+import { Schema } from "effect"
+import { ascending } from "./identifier"
+import { withStatics } from "./schema"
+
+export const ID = Schema.String.check(Schema.isStartsWith("wrk")).pipe(
+  Schema.brand("WorkspaceV2.ID"),
+  withStatics((schema) => ({
+    ascending: (id?: string) => {
+      if (id === undefined) return schema.make("wrk_" + ascending())
+      if (!id.startsWith("wrk")) throw new Error(`ID ${id} does not start with wrk`)
+      return schema.make(id)
+    },
+    create: () => schema.make("wrk_" + ascending()),
+  })),
+)
+export type ID = typeof ID.Type

packages/schema/tsconfig.json

@@ -0,0 +1,8 @@
+{
+  "$schema": "https://json.schemastore.org/tsconfig",
+  "extends": "@tsconfig/bun/tsconfig.json",
+  "compilerOptions": {
+    "lib": ["ESNext", "DOM", "DOM.Iterable"],
+    "noUncheckedIndexedAccess": false
+  }
+}

packages/sdk-next/README.md

@@ -0,0 +1,27 @@
+# @opencode-ai/sdk-next
+
+Effect-native scoped OpenCode host for in-process applications. This transitional package will replace the existing generated `@opencode-ai/sdk` after its consumers migrate.
+
+The SDK executes Server's assembled HTTP router in memory. It opens no listener and performs no network I/O, while preserving the same routing, middleware, handlers, codecs, and errors as the network client.
+
+```ts
+import { OpenCode } from "@opencode-ai/sdk-next"
+
+const opencode = yield * OpenCode.create()
+const session = yield * opencode.sessions.get({ sessionID })
+```
+
+It also exposes local-only `tools.register(...)`. Closing the owning Effect Scope releases router resources, location services, fibers, and scoped tool registrations.
+
+The same constructor is available as a service Layer:
+
+```ts
+const program = Effect.gen(function* () {
+  const opencode = yield* OpenCode.Service
+  return yield* opencode.sessions.get({ sessionID })
+})
+
+yield * program.pipe(Effect.provide(OpenCode.layer))
+```
+
+`OpenCode.layer` adapts `OpenCode.create()` for dependency injection; it does not define another host implementation.

packages/sdk-next/package.json

@@ -0,0 +1,25 @@
+{
+  "$schema": "https://json.schemastore.org/package.json",
+  "name": "@opencode-ai/sdk-next",
+  "private": true,
+  "type": "module",
+  "license": "MIT",
+  "exports": {
+    ".": "./src/index.ts"
+  },
+  "scripts": {
+    "test": "bun test --timeout 5000",
+    "typecheck": "tsgo --noEmit"
+  },
+  "dependencies": {
+    "@opencode-ai/client": "workspace:*",
+    "@opencode-ai/core": "workspace:*",
+    "@opencode-ai/server": "workspace:*",
+    "effect": "catalog:"
+  },
+  "devDependencies": {
+    "@tsconfig/bun": "catalog:",
+    "@types/bun": "catalog:",
+    "@typescript/native-preview": "catalog:"
+  }
+}

packages/sdk-next/src/index.ts

@@ -0,0 +1,16 @@
+export * as OpenCode from "./opencode"
+
+export { ClientError } from "@opencode-ai/client/effect"
+export { Tool } from "@opencode-ai/core/public/tool"
+export {
+  AbsolutePath,
+  Agent,
+  Location,
+  Model,
+  Prompt,
+  Provider,
+  RelativePath,
+  Session,
+  SessionInput,
+  SessionMessage,
+} from "@opencode-ai/client/effect"

packages/sdk-next/src/opencode.ts

@@ -0,0 +1,49 @@
+import { OpenCode } from "@opencode-ai/client/effect"
+import { PermissionSaved } from "@opencode-ai/core/permission/saved"
+import { ApplicationTools } from "@opencode-ai/core/tool/application-tools"
+import { createEmbeddedRoutes } from "@opencode-ai/server/routes"
+import { Cause, Context, Effect, Layer } from "effect"
+import {
+  HttpClient,
+  HttpRouter,
+  HttpServer,
+  HttpServerError,
+  HttpServerRequest,
+  HttpServerResponse,
+} from "effect/unstable/http"
+
+export const create = Effect.fn("OpenCode.create")(function* () {
+  const { handler, permissions, tools } = yield* Effect.all({
+    handler: HttpRouter.toHttpEffect(createEmbeddedRoutes().pipe(Layer.provide(HttpServer.layerServices))),
+    permissions: PermissionSaved.Service,
+    tools: ApplicationTools.Service,
+  }).pipe(Effect.provide(Layer.merge(ApplicationTools.layer, PermissionSaved.defaultLayer)))
+  const httpClient = HttpClient.make(
+    Effect.fnUntraced(function* (request) {
+      const response = yield* handler.pipe(
+        Effect.provideService(HttpServerRequest.HttpServerRequest, HttpServerRequest.fromClientRequest(request)),
+        Effect.provideService(ApplicationTools.Service, tools),
+        Effect.provideService(PermissionSaved.Service, permissions),
+        Effect.catchCause((cause) =>
+          Cause.hasInterruptsOnly(cause)
+            ? Effect.interrupt
+            : HttpServerError.causeResponse(cause).pipe(Effect.map(([response]) => response)),
+        ),
+      )
+      return HttpServerResponse.toClientResponse(response, { request })
+    }, Effect.scoped),
+  )
+  const client = yield* OpenCode.make({ baseUrl: "http://opencode.local" }).pipe(
+    Effect.provideService(HttpClient.HttpClient, httpClient),
+  )
+  return {
+    ...client,
+    tools: { register: tools.register },
+  }
+})
+
+export type Interface = Effect.Success<ReturnType<typeof create>>
+
+export class Service extends Context.Service<Service, Interface>()("@opencode-ai/sdk-next/OpenCode") {}
+
+export const layer = Layer.effect(Service, create())

packages/sdk-next/test/embedded.test.ts

@@ -0,0 +1,84 @@
+import { expect, test } from "bun:test"
+import { mkdtemp, rm } from "node:fs/promises"
+import { tmpdir } from "node:os"
+import { join } from "node:path"
+import { Flag } from "@opencode-ai/core/flag/flag"
+import { Effect, Schema } from "effect"
+
+test("embedded client uses the real router and handlers", async () => {
+  const directory = await mkdtemp(join(tmpdir(), "opencode-embedded-"))
+  const database = Flag.OPENCODE_DB
+  Flag.OPENCODE_DB = join(directory, "opencode.sqlite")
+  const { AbsolutePath, Agent, Location, Model, OpenCode, Prompt, Provider, Session, Tool } = await import("../src")
+  const sessionID = Session.ID.make(`ses_embedded_${crypto.randomUUID()}`)
+  const model = Model.Ref.make({ id: Model.ID.make("embedded"), providerID: Provider.ID.make("test") })
+
+  try {
+    const program = Effect.gen(function* () {
+      const opencode = yield* OpenCode.create()
+      yield* opencode.tools.register({
+        embedded_tool: Tool.make({
+          description: "Embedded test tool",
+          input: Schema.Struct({}),
+          output: Schema.Struct({ ok: Schema.Boolean }),
+          execute: () => Effect.succeed({ ok: true }),
+        }),
+      })
+
+      const created = yield* opencode.sessions.create({
+        id: sessionID,
+        agent: Agent.ID.make("build"),
+        location: Location.Ref.make({ directory: AbsolutePath.make(directory) }),
+      })
+      yield* opencode.sessions.switchModel({ sessionID, model })
+      const selected = yield* opencode.sessions.get({ sessionID })
+      const page = yield* opencode.sessions.list({ directory: AbsolutePath.make(directory) })
+      const admitted = yield* opencode.sessions.prompt({
+        sessionID,
+        prompt: Prompt.make({ text: "Do not run" }),
+        resume: false,
+      })
+      const context = yield* opencode.sessions.context({ sessionID })
+      const missing = yield* Effect.flip(
+        opencode.sessions.get({ sessionID: Session.ID.make(`ses_missing_${crypto.randomUUID()}`) }),
+      )
+
+      expect(created.id).toBe(sessionID)
+      expect(selected.model?.id).toBe(model.id)
+      expect(selected.model?.providerID).toBe(model.providerID)
+      expect(page.data.some((session) => session.id === sessionID)).toBe(true)
+      expect(admitted.sessionID).toBe(sessionID)
+      expect(context.some((message) => message.type === "model-switched")).toBe(true)
+      expect(missing._tag).toBe("SessionNotFoundError")
+    })
+    await Effect.runPromise(Effect.scoped(program))
+  } finally {
+    Flag.OPENCODE_DB = database
+    await rm(directory, { recursive: true, force: true })
+  }
+})
+
+test("embedded client is available as a Layer service", async () => {
+  const directory = await mkdtemp(join(tmpdir(), "opencode-embedded-layer-"))
+  const database = Flag.OPENCODE_DB
+  Flag.OPENCODE_DB = join(directory, "opencode.sqlite")
+  const { AbsolutePath, Location, OpenCode, Session } = await import("../src")
+  const sessionID = Session.ID.make(`ses_embedded_${crypto.randomUUID()}`)
+
+  try {
+    const created = await Effect.runPromise(
+      Effect.gen(function* () {
+        const opencode = yield* OpenCode.Service
+        return yield* opencode.sessions.create({
+          id: sessionID,
+          location: Location.Ref.make({ directory: AbsolutePath.make(directory) }),
+        })
+      }).pipe(Effect.provide(OpenCode.layer), Effect.scoped),
+    )
+
+    expect(created.id).toBe(sessionID)
+  } finally {
+    Flag.OPENCODE_DB = database
+    await rm(directory, { recursive: true, force: true })
+  }
+})

packages/sdk-next/test/import-boundaries.test.ts

@@ -0,0 +1,53 @@
+import { expect, test } from "bun:test"
+import { mkdtemp, rm } from "node:fs/promises"
+import { join, resolve, sep } from "node:path"
+
+const directory = resolve(import.meta.dir, "..")
+const client = resolve(import.meta.dir, "../../client")
+const core = resolve(import.meta.dir, "../../core")
+const server = resolve(import.meta.dir, "../../server")
+
+test("bundles the client and in-memory host", async () => {
+  const inputs = await bundleInputs()
+
+  expect(within(inputs, client).length).toBeGreaterThan(0)
+  expect(within(inputs, core).length).toBeGreaterThan(0)
+  expect(within(inputs, server).length).toBeGreaterThan(0)
+})
+
+async function bundleInputs() {
+  const temporary = await mkdtemp(join(import.meta.dir, ".import-boundary-"))
+  const entrypoint = join(temporary, "index.ts")
+  const metafile = join(temporary, "meta.json")
+  try {
+    await Bun.write(entrypoint, 'export * from "@opencode-ai/sdk-next"')
+    const child = Bun.spawn(
+      [
+        process.execPath,
+        "build",
+        entrypoint,
+        "--target=bun",
+        "--format=esm",
+        "--packages=bundle",
+        `--metafile=${metafile}`,
+        `--outdir=${join(temporary, "out")}`,
+      ],
+      { cwd: directory, stdout: "pipe", stderr: "pipe" },
+    )
+    const [exitCode, stdout, stderr] = await Promise.all([
+      child.exited,
+      new Response(child.stdout).text(),
+      new Response(child.stderr).text(),
+    ])
+    if (exitCode !== 0) throw new Error(stdout + stderr)
+    const metadata = await Bun.file(metafile).json()
+    return Object.keys(metadata.inputs).map((input) => resolve(directory, input))
+  } finally {
+    await rm(temporary, { recursive: true, force: true })
+  }
+}
+
+function within(inputs: ReadonlyArray<string>, directory: string) {
+  const prefix = directory.endsWith(sep) ? directory : directory + sep
+  return inputs.filter((input) => input === directory || input.startsWith(prefix))
+}

packages/sdk-next/tsconfig.json

@@ -0,0 +1,8 @@
+{
+  "$schema": "https://json.schemastore.org/tsconfig",
+  "extends": "@tsconfig/bun/tsconfig.json",
+  "compilerOptions": {
+    "lib": ["ESNext", "DOM", "DOM.Iterable"],
+    "noUncheckedIndexedAccess": false
+  }
+}

packages/server/package.json

@@ -13,6 +13,7 @@
   },
   "dependencies": {
     "@opencode-ai/core": "workspace:*",
+    "@opencode-ai/protocol": "workspace:*",
     "drizzle-orm": "catalog:",
     "effect": "catalog:"
   },

packages/server/src/api.ts

@@ -3,7 +3,7 @@ import { SchemaErrorMiddleware } from "./middleware/schema-error"
 import { MessageGroup } from "./groups/message"
 import { ModelGroup } from "./groups/model"
 import { ProviderGroup } from "./groups/provider"
-import { SessionGroup } from "./groups/session"
+import { SessionGroup } from "@opencode-ai/protocol/session"
 import { PermissionGroup } from "./groups/permission"
 import { FileSystemGroup } from "./groups/fs"
 import { CommandGroup } from "./groups/command"

packages/server/src/errors.ts

@@ -1,101 +1 @@
-import { Schema } from "effect"
-
-export class InvalidRequestError extends Schema.TaggedErrorClass<InvalidRequestError>()(
-  "InvalidRequestError",
-  {
-    message: Schema.String,
-    kind: Schema.optional(Schema.String),
-    field: Schema.optional(Schema.String),
-  },
-  { httpApiStatus: 400 },
-) {}
-
-export class UnauthorizedError extends Schema.TaggedErrorClass<UnauthorizedError>()(
-  "UnauthorizedError",
-  { message: Schema.String },
-  { httpApiStatus: 401 },
-) {}
-
-export class ConflictError extends Schema.TaggedErrorClass<ConflictError>()(
-  "ConflictError",
-  {
-    message: Schema.String,
-    resource: Schema.optional(Schema.String),
-  },
-  { httpApiStatus: 409 },
-) {}
-
-export class ServiceUnavailableError extends Schema.TaggedErrorClass<ServiceUnavailableError>()(
-  "ServiceUnavailableError",
-  {
-    message: Schema.String,
-    service: Schema.optional(Schema.String),
-  },
-  { httpApiStatus: 503 },
-) {}
-
-export class UnknownError extends Schema.TaggedErrorClass<UnknownError>()(
-  "UnknownError",
-  {
-    message: Schema.String,
-    ref: Schema.optional(Schema.String),
-  },
-  { httpApiStatus: 500 },
-) {}
-
-export class ProviderNotFoundError extends Schema.TaggedErrorClass<ProviderNotFoundError>()(
-  "ProviderNotFoundError",
-  {
-    providerID: Schema.String,
-    message: Schema.String,
-  },
-  { httpApiStatus: 404 },
-) {}
-
-export class SessionNotFoundError extends Schema.TaggedErrorClass<SessionNotFoundError>()(
-  "SessionNotFoundError",
-  {
-    sessionID: Schema.String,
-    message: Schema.String,
-  },
-  { httpApiStatus: 404 },
-) {}
-
-export class InvalidCursorError extends Schema.TaggedErrorClass<InvalidCursorError>()(
-  "InvalidCursorError",
-  { message: Schema.String },
-  { httpApiStatus: 400 },
-) {}
-
-export class PermissionNotFoundError extends Schema.TaggedErrorClass<PermissionNotFoundError>()(
-  "PermissionNotFoundError",
-  {
-    requestID: Schema.String,
-    message: Schema.String,
-  },
-  { httpApiStatus: 404 },
-) {}
-
-export class QuestionNotFoundError extends Schema.TaggedErrorClass<QuestionNotFoundError>()(
-  "QuestionNotFoundError",
-  {
-    requestID: Schema.String,
-    message: Schema.String,
-  },
-  { httpApiStatus: 404 },
-) {}
-
-export class ForbiddenError extends Schema.TaggedErrorClass<ForbiddenError>()(
-  "ForbiddenError",
-  { message: Schema.String },
-  { httpApiStatus: 403 },
-) {}
-
-export class PtyNotFoundError extends Schema.TaggedErrorClass<PtyNotFoundError>()(
-  "PtyNotFoundError",
-  {
-    ptyID: Schema.String,
-    message: Schema.String,
-  },
-  { httpApiStatus: 404 },
-) {}
+export * from "@opencode-ai/protocol/errors"