fix(provider): default custom models to image input

Co-authored-by: Devin Oldenburg <devin@logicplanes.com>

.github/workflows/test.yml

@@ -65,7 +65,7 @@ jobs:
 
       - name: Run unit tests
         timeout-minutes: 20
-        run: bun turbo test --output-logs=errors-only --log-order=grouped --log-prefix=task
+        run: bun turbo test --output-logs=errors-only --log-order=grouped --log-prefix=none
         env:
           OPENCODE_EXPERIMENTAL_DISABLE_FILEWATCHER: ${{ runner.os == 'Windows' && 'true' || 'false' }}
 
@@ -99,7 +99,8 @@ jobs:
       - name: Setup Node
         uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4.4.0
         with:
-          node-version: "24"
+          # Playwright 1.59 hangs while extracting Chromium with Node 24.16.
+          node-version: "24.15"
 
       - name: Setup Bun
         uses: ./.github/actions/setup-bun

AGENTS.md

@@ -137,7 +137,7 @@ const table = sqliteTable("session", {
 
 ## Testing
 
-- Avoid mocks as much as possible
+- Avoid mocks as much as possible, you shouldn't be using globalThis.\* at all unless it's the only option.
 - Test actual implementation, do not duplicate logic into tests
 - Tests cannot run from repo root (guard: `do-not-run-tests-from-root`); run from package dirs like `packages/opencode`.
 

CONTEXT.md

@@ -24,7 +24,7 @@ A durable chronological instruction that tells the model the newly effective sta
 _Avoid_: System update, system notification, raw text diff
 
 **Context Epoch**:
-The span during which one effective agent's initially rendered **System Context** remains immutable, ending at compaction or another baseline-replacing transition.
+The span during which one initially rendered **System Context** remains the immutable provider-cache baseline, ending at completed compaction, Session movement, or an incompatible context transition that requires a fresh baseline.
 
 **Baseline System Context**:
 The full **System Context** rendered at the start of a **Context Epoch**.
@@ -75,31 +75,28 @@ The host-supplied environment overlay applied by the server when creating a PTY,
 - Each **Context Source** loader returns one coherent typed value. `SystemContext.make(...)` hides that value type so differently typed sources compose uniformly. Its codec compares and stores that value; its pure renderers produce model-visible baseline, update, and removal text only when needed.
 - `SystemContext.initialize(...)` observes a composed **System Context** once and produces a fresh **Baseline System Context** with its **Context Snapshot**.
 - `SystemContext.reconcile(...)` observes a composed **System Context** once and returns exactly one next action: unchanged, updated, replacement ready, or replacement blocked.
-- `SystemContext.replace(...)` represents an explicit baseline-replacing transition such as compaction or model/provider switch; it either produces a fresh generation or reports that replacement is blocked by unavailable admitted context.
-- Context Epoch preparation retries until stable after optimistic revision mismatches so concurrent replacement requests cannot terminate an otherwise valid safe-boundary run.
+- `SystemContext.replace(...)` renders a fresh generation after completed compaction or another baseline-replacing transition; it reports replacement blocked while previously admitted context is unavailable.
 - **Unavailable Context** uses stale-while-revalidate semantics and is distinct from a successfully loaded absence, which may emit removal text.
 - Ordinary **Context Source** loaders return values directly; loaders that intentionally use stale-while-revalidate may explicitly return **Unavailable Context**.
 - Nested project instruction discovery after successful reads remains a follow-up; when implemented, discovered instructions must be admitted durably at the next **Safe Provider-Turn Boundary**.
 - Location-scoped services naturally re-resolve effective context when a moved session next runs in its destination location.
 - Moving a Session clears its active **Context Epoch**, so the destination must initialize a complete baseline before another prompt can promote.
-- Context Epoch initialization is fenced against the authoritative Session Location, so an old-Location runner cannot recreate source context after a concurrent move.
 - Instruction discovery, source identity, persistence, and file loading belong to the instruction service; the **System Context** abstraction only composes effectful producers and renders loaded values.
 - The first instruction-service slice observes global and upward project `AGENTS.md` files as one ordered aggregate **Context Source** at each **Safe Provider-Turn Boundary**.
 - Built-in and instruction context producers register through the **System Context Registry** with stable contribution keys. Plugin-defined context registration and hot-reload lifecycle remain a follow-up built on the same scoped registry seam.
 - Selected-agent available-skill guidance is a **Context Source** composed with Location-wide registry sources immediately before Context Epoch admission. It lists only names and descriptions permitted for that agent; skill bodies and locations are exposed only through the permission-checked `skill` tool.
-- Switching the selected agent requests **Context Epoch** replacement. A switch admitted after the current **Safe Provider-Turn Boundary** applies to the next provider turn while leaving the already-prepared baseline durable. Epoch creation is fenced against the authoritative effective agent, and retries re-observe the current agent.
-- A cross-agent replacement must complete before another provider turn; unavailable admitted context blocks that replacement instead of exposing the previous agent's privileged baseline.
+- The selected agent and model are sampled when a provider turn starts. Changes admitted after that boundary apply to the next provider turn and do not restart the current turn.
+- Selected-agent available-skill guidance remains a **Context Source**. An agent switch that changes that guidance produces a **Mid-Conversation System Message** while preserving the current baseline.
 - Local tool authorization and pending permission requests retain the effective agent of the provider turn that issued the call; a later agent switch cannot change that call's policy.
 - Context source changes never wake idle sessions; the next naturally scheduled **Safe Provider-Turn Boundary** loads and compares current values lazily.
 - Once admitted, a **Mid-Conversation System Message** remains durable even if the following provider attempt fails and is replayed unchanged on retry.
 - **Mid-Conversation System Messages** remain durable Session-message history; normal user-facing transcript surfaces may hide them.
 - The date **Context Source** initially preserves host-local calendar-date behavior; a configured user timezone may replace that default later.
 - A **Context Epoch** begins with one immutable **Baseline System Context**.
-- A **Context Epoch** durably records the effective agent that owns its **Baseline System Context**.
 - A **Baseline System Context** is stored durably and reused verbatim across process restarts within its **Context Epoch**.
 - A **Baseline System Context** durably preserves the exact joined text used for the active provider-cache prefix.
-- Compaction or a model/provider switch starts a new **Context Epoch** because the baseline can be replaced without preserving the prior provider cache.
-- A model/provider switch always starts a new **Context Epoch** while preserving chronological conversation history.
+- Completed compaction starts a new **Context Epoch** on the next provider attempt, folding the current complete **System Context** into a fresh baseline and removing earlier **Mid-Conversation System Messages** from active model history.
+- A model/provider switch preserves the current **Context Epoch** and chronological conversation history; the new selection applies to the next provider turn.
 - **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`.

nix/hashes.json

@@ -1,8 +1,8 @@
 {
   "nodeModules": {
-    "x86_64-linux": "sha256-g0tDvRf7MErZ1PEeUazEYi492ZHiRT8kYv3bPdkss/I=",
-    "aarch64-linux": "sha256-6sKgf3ftbIqlPxlFkoPzoWPsJp3IwXD+H3Y6g874xmk=",
-    "aarch64-darwin": "sha256-Se/Nls/KlkuK2ysDQ9DeAzSaX3NsL2iDdf/dsv2GIXc=",
-    "x86_64-darwin": "sha256-V9MCkqnvQ1nkD2PaaTfNFKkBZGymj6KxrSAK6+DTF8Y="
+    "x86_64-linux": "sha256-oWSGu+SP66Aquy/0Vaq7Bgp8404ZdOWbQX+O7h3jxHU=",
+    "aarch64-linux": "sha256-UsS0+c+GwtIukmWwQeFbY/3Oaz3t4Q7C6cFMGkmlyAY=",
+    "aarch64-darwin": "sha256-CArz92ewPmXO+ORFCBkCH8LzMpU/DjyaO4ic7QL0UpI=",
+    "x86_64-darwin": "sha256-rhnz9gmG6L06wIzfMhTaXDDEf6IbMD32CavqwXoqcUs="
   }
 }

packages/cli/src/commands/handlers/serve.ts

@@ -27,9 +27,11 @@ export default Runtime.handler(
 
 function listen(hostname: string, port: Option.Option<number>, password: string) {
   if (Option.isSome(port)) return bind(hostname, port.value, password)
-  // Preserve the familiar default when available, but let the OS choose a free
-  // port when another local server already owns 4096.
-  return bind(hostname, 4096, password).pipe(Effect.catch(() => bind(hostname, 0, password)))
+  const next = (port: number): ReturnType<typeof bind> =>
+    bind(hostname, port, password).pipe(
+      Effect.catch((error) => (port === 65_535 ? Effect.fail(error) : next(port + 1))),
+    )
+  return next(4096)
 }
 
 function bind(hostname: string, port: number, password: string) {

packages/console/app/src/routes/zen/util/handler.ts

@@ -196,6 +196,13 @@ export async function handler(
           Object.entries(providerInfo.headerMappings ?? {}).forEach(([k, v]) => {
             headers.set(k, headers.get(v)!)
           })
+          Object.entries(providerInfo.headerModifier ?? {}).forEach(([k, v]) => {
+            if (v === "$ip") return headers.set(k, ip)
+            if (v === "$session") return headers.set(k, sessionId)
+            if (v === "$model") return headers.set(k, model)
+            if (v === "$request") return headers.set(k, requestId)
+            headers.set(k, v)
+          })
           headers.delete("host")
           headers.delete("content-length")
           headers.delete("x-opencode-request")

packages/console/core/src/model.ts

@@ -53,6 +53,7 @@ export namespace ZenData {
     apiKey: z.union([z.string(), z.record(z.string(), z.string())]),
     format: FormatSchema.optional(),
     headerMappings: z.record(z.string(), z.string()).optional(),
+    headerModifier: z.record(z.string(), z.any()).optional(),
     payloadModifier: z.record(z.string(), z.any()).optional(),
     payloadMappings: z.record(z.string(), z.string()).optional(),
     adjustCacheUsage: z.boolean().optional(),

packages/core/bunfig.toml

@@ -0,0 +1,2 @@
+[test]
+preload = ["./test/preload.ts"]

packages/core/schema.json

@@ -1,8 +1,8 @@
 {
   "version": "7",
   "dialect": "sqlite",
-  "id": "169a0f0f-d58f-479f-b024-fa1c7b9a09db",
-  "prevIds": ["abd2f920-b822-49af-b8a7-2e48367d424f"],
+  "id": "f14a9b18-8207-487e-a3d3-227e629ba9ad",
+  "prevIds": ["169a0f0f-d58f-479f-b024-fa1c7b9a09db"],
   "ddl": [
     {
       "name": "workspace",
@@ -900,16 +900,6 @@
       "entityType": "columns",
       "table": "session_context_epoch"
     },
-    {
-      "type": "text",
-      "notNull": true,
-      "autoincrement": false,
-      "default": "'build'",
-      "generated": null,
-      "name": "agent",
-      "entityType": "columns",
-      "table": "session_context_epoch"
-    },
     {
       "type": "text",
       "notNull": true,
@@ -930,26 +920,6 @@
       "entityType": "columns",
       "table": "session_context_epoch"
     },
-    {
-      "type": "integer",
-      "notNull": false,
-      "autoincrement": false,
-      "default": null,
-      "generated": null,
-      "name": "replacement_seq",
-      "entityType": "columns",
-      "table": "session_context_epoch"
-    },
-    {
-      "type": "integer",
-      "notNull": true,
-      "autoincrement": false,
-      "default": "0",
-      "generated": null,
-      "name": "revision",
-      "entityType": "columns",
-      "table": "session_context_epoch"
-    },
     {
       "type": "text",
       "notNull": false,

packages/core/script/migration.ts

@@ -45,15 +45,17 @@ async function generate() {
       if (await Bun.file(target).exists()) throw new Error(`Database migration already exists: ${name}`)
       await Bun.write(
         target,
-        renderMigration(name, await Bun.file(path.join(incremental, name, "migration.sql")).text()),
+        await formatTypescript(
+          renderMigration(name, await Bun.file(path.join(incremental, name, "migration.sql")).text()),
+        ),
       )
       await fs.copyFile(path.join(incremental, name, "snapshot.json"), snapshot)
     }
 
     await fs.mkdir(full)
     await drizzle(temporary, full, "schema")
-    await Bun.write(schema, renderSchema(await generatedSql(full)))
-    await Bun.write(registry, renderRegistry(await typescriptMigrations()))
+    await Bun.write(schema, await formatTypescript(renderSchema(await generatedSql(full))))
+    await Bun.write(registry, await formatTypescript(renderRegistry(await typescriptMigrations())))
   } finally {
     await fs.rm(temporary, { recursive: true, force: true })
   }
@@ -76,12 +78,12 @@ async function check() {
 
     await fs.mkdir(full)
     await drizzle(temporary, full, "schema")
-    if ((await Bun.file(schema).text()) !== renderSchema(await generatedSql(full))) {
+    if ((await Bun.file(schema).text()) !== (await formatTypescript(renderSchema(await generatedSql(full))))) {
       throw new Error("Current database schema is stale. Run `bun script/migration.ts` from packages/core.")
     }
 
     const migrations = await typescriptMigrations()
-    if ((await Bun.file(registry).text()) !== renderRegistry(migrations)) {
+    if ((await Bun.file(registry).text()) !== (await formatTypescript(renderRegistry(migrations)))) {
       throw new Error("Database migration registry is stale. Run `bun script/migration.ts` from packages/core.")
     }
   } finally {
@@ -170,6 +172,18 @@ function escapeTemplate(line: string) {
   return line.replaceAll("\\", "\\\\").replaceAll("`", "\\`").replaceAll("${", "\\${")
 }
 
+async function formatTypescript(input: string) {
+  const prettier = await import("prettier")
+  const typescript = await import("prettier/plugins/typescript")
+  const estree = await import("prettier/plugins/estree")
+  return prettier.format(input, {
+    parser: "typescript",
+    plugins: [typescript.default, estree.default],
+    semi: false,
+    printWidth: 120,
+  })
+}
+
 function renderRegistry(names: string[]) {
   return `import type { DatabaseMigration } from "./migration"
 

packages/core/src/catalog.ts

@@ -69,10 +69,10 @@ export const layer = Layer.effect(
     const policy = yield* Policy.Service
     const integrations = yield* Integration.Service
 
-    const available = (provider: ProviderV2.Info, integration: Integration.Info | undefined, connected: boolean) => {
+    const available = (provider: ProviderV2.Info, integration: Integration.Info | undefined) => {
       if (provider.disabled) return false
       if (typeof provider.request.body.apiKey === "string") return true
-      if (connected) return true
+      if (integration?.connections.length) return true
       return !integration
     }
 
@@ -183,13 +183,8 @@ export const layer = Layer.effect(
 
         available: Effect.fn("CatalogV2.provider.available")(function* () {
           const active = new Map((yield* integrations.list()).map((integration) => [integration.id, integration]))
-          const connections = yield* integrations.connection.list()
           return (yield* result.provider.all()).filter((provider) =>
-            available(
-              provider,
-              active.get(Integration.ID.make(provider.id)),
-              connections.has(Integration.ID.make(provider.id)),
-            ),
+            available(provider, active.get(Integration.ID.make(provider.id))),
           )
         }),
       },

packages/core/src/config/plugin/provider.ts

@@ -63,16 +63,22 @@ export const Plugin = define({
             const providerPackage = providerApi?.type === "aisdk" ? providerApi.package : undefined
 
             for (const [id, config] of Object.entries(item.models ?? {})) {
+              const existing = catalog.model.get(providerID, id)
               catalog.model.update(providerID, id, (model) => {
                 if (config.family !== undefined) model.family = config.family
                 if (config.name !== undefined) model.name = config.name
                 if (config.api !== undefined) model.api = { ...model.api, ...config.api }
                 const packageName = model.api.type === "aisdk" ? model.api.package : providerPackage
+                // TODO: Move these defaults to a dedicated configured-model constructor when one exists.
+                if (existing === undefined) {
+                  model.capabilities.input = ["text", "image"]
+                  model.capabilities.output = ["text"]
+                }
                 if (config.capabilities !== undefined) {
                   model.capabilities = {
-                    tools: config.capabilities.tools,
-                    input: [...config.capabilities.input],
-                    output: [...config.capabilities.output],
+                    tools: config.capabilities.tools ?? model.capabilities.tools,
+                    input: [...(config.capabilities.input ?? model.capabilities.input)],
+                    output: [...(config.capabilities.output ?? model.capabilities.output)],
                   }
                 }
                 if (config.request !== undefined) {

packages/core/src/config/provider.ts

@@ -44,11 +44,17 @@ const ModelApi = Schema.Union([
   }),
 ])
 
+class Capabilities extends Schema.Class<Capabilities>("ConfigV2.Model.Capabilities")({
+  tools: ModelV2.Capabilities.fields.tools.pipe(Schema.optional),
+  input: ModelV2.Capabilities.fields.input.pipe(Schema.optional),
+  output: ModelV2.Capabilities.fields.output.pipe(Schema.optional),
+}) {}
+
 class Model extends Schema.Class<Model>("ConfigV2.Model")({
   family: ModelV2.Family.pipe(Schema.optional),
   name: Schema.String.pipe(Schema.optional),
   api: ModelApi.pipe(Schema.optional),
-  capabilities: ModelV2.Capabilities.pipe(Schema.optional),
+  capabilities: Capabilities.pipe(Schema.optional),
   request: Schema.Struct({
     ...Request.fields,
     variant: Schema.String.pipe(Schema.optional),

packages/core/src/credential.ts

@@ -29,33 +29,33 @@ export class Key extends Schema.Class<Key>("Credential.Key")({
   metadata: Schema.optional(Schema.Record(Schema.String, Schema.String)),
 }) {}
 
-export const Info = Schema.Union([OAuth, Key])
+export const Value = Schema.Union([OAuth, Key])
   .pipe(Schema.toTaggedUnion("type"))
-  .annotate({ identifier: "Credential.Info" })
-export type Info = Schema.Schema.Type<typeof Info>
+  .annotate({ identifier: "Credential.Value" })
+export type Value = Schema.Schema.Type<typeof Value>
 
-export class Stored extends Schema.Class<Stored>("Credential.Stored")({
+export class Info extends Schema.Class<Info>("Credential.Info")({
   id: ID,
   integrationID: IntegrationSchema.ID,
   label: Schema.String,
-  value: Info,
+  value: Value,
 }) {}
 
 export interface Interface {
   /** Returns every stored credential. */
-  readonly all: () => Effect.Effect<Stored[]>
+  readonly all: () => Effect.Effect<Info[]>
   /** Returns stored credentials belonging to one integration. */
-  readonly list: (integrationID: IntegrationSchema.ID) => Effect.Effect<Stored[]>
+  readonly list: (integrationID: IntegrationSchema.ID) => Effect.Effect<Info[]>
   /** Returns one stored credential by ID. */
-  readonly get: (id: ID) => Effect.Effect<Stored | undefined>
+  readonly get: (id: ID) => Effect.Effect<Info | undefined>
   /** Replaces any credential for an integration and returns the new record. */
   readonly create: (input: {
     readonly integrationID: IntegrationSchema.ID
-    readonly value: Info
+    readonly value: Value
     readonly label?: string
-  }) => Effect.Effect<Stored>
+  }) => Effect.Effect<Info>
   /** Updates the label or secret value of a stored credential. */
-  readonly update: (id: ID, updates: Partial<Pick<Stored, "label" | "value">>) => Effect.Effect<void>
+  readonly update: (id: ID, updates: Partial<Pick<Info, "label" | "value">>) => Effect.Effect<void>
   /** Removes a stored credential. */
   readonly remove: (id: ID) => Effect.Effect<void>
 }
@@ -66,10 +66,10 @@ export const layer = Layer.effect(
   Service,
   Effect.gen(function* () {
     const { db } = yield* Database.Service
-    const decode = Schema.decodeUnknownSync(Info)
+    const decode = Schema.decodeUnknownSync(Value)
     const stored = (row: typeof CredentialTable.$inferSelect) => {
       if (!row.integration_id) return
-      return new Stored({
+      return new Info({
         id: row.id,
         integrationID: row.integration_id,
         label: row.label,
@@ -106,7 +106,7 @@ export const layer = Layer.effect(
         return row ? stored(row) : undefined
       }),
       create: Effect.fn("Credential.create")(function* (input) {
-        const credential = new Stored({
+        const credential = new Info({
           id: ID.create(),
           integrationID: input.integrationID,
           label: input.label ?? "default",

packages/core/src/credential/sql.ts

@@ -7,7 +7,7 @@ export const CredentialTable = sqliteTable("credential", {
   id: text().$type<Credential.ID>().primaryKey(),
   integration_id: text().$type<IntegrationSchema.ID>(),
   label: text().notNull(),
-  value: text({ mode: "json" }).$type<Credential.Info>().notNull(),
+  value: text({ mode: "json" }).$type<Credential.Value>().notNull(),
   connector_id: text(),
   method_id: text(),
   active: integer({ mode: "boolean" }),

packages/core/src/database/migration.gen.ts

@@ -37,5 +37,7 @@ export const migrations = (
     import("./migration/20260611035744_credential"),
     import("./migration/20260611192811_lush_chimera"),
     import("./migration/20260612174303_project_dir_strategy"),
+    import("./migration/20260622142730_simplify_session_context_epoch"),
+    import("./migration/20260622170816_reset_v2_session_state"),
   ])
 ).map((module) => module.default) satisfies DatabaseMigration.Migration[]

packages/core/src/database/migration/20260622142730_simplify_session_context_epoch.ts

@@ -0,0 +1,13 @@
+import { Effect } from "effect"
+import type { DatabaseMigration } from "../migration"
+
+export default {
+  id: "20260622142730_simplify_session_context_epoch",
+  up(tx) {
+    return Effect.gen(function* () {
+      yield* tx.run(`ALTER TABLE \`session_context_epoch\` DROP COLUMN \`agent\`;`)
+      yield* tx.run(`ALTER TABLE \`session_context_epoch\` DROP COLUMN \`replacement_seq\`;`)
+      yield* tx.run(`ALTER TABLE \`session_context_epoch\` DROP COLUMN \`revision\`;`)
+    })
+  },
+} satisfies DatabaseMigration.Migration

packages/core/src/database/migration/20260622170816_reset_v2_session_state.ts

@@ -0,0 +1,17 @@
+import { Effect } from "effect"
+import type { DatabaseMigration } from "../migration"
+
+export default {
+  id: "20260622170816_reset_v2_session_state",
+  up(tx) {
+    return Effect.gen(function* () {
+      yield* tx.run(`DELETE FROM \`session_context_epoch\`;`)
+      yield* tx.run(`DELETE FROM \`session_input\`;`)
+      yield* tx.run(`DELETE FROM \`session_message\`;`)
+      yield* tx.run(`DELETE FROM \`event\`;`)
+      yield* tx.run(`DELETE FROM \`event_sequence\`;`)
+      yield* tx.run(`UPDATE \`session\` SET \`workspace_id\` = NULL WHERE \`workspace_id\` IS NOT NULL;`)
+      yield* tx.run(`DELETE FROM \`workspace\`;`)
+    })
+  },
+} satisfies DatabaseMigration.Migration

packages/core/src/database/schema.gen.ts

@@ -149,11 +149,8 @@ export default {
         CREATE TABLE \`session_context_epoch\` (
           \`session_id\` text PRIMARY KEY,
           \`baseline\` text NOT NULL,
-          \`agent\` text DEFAULT 'build' NOT NULL,
           \`snapshot\` text NOT NULL,
           \`baseline_seq\` integer NOT NULL,
-          \`replacement_seq\` integer,
-          \`revision\` integer DEFAULT 0 NOT NULL,
           CONSTRAINT \`fk_session_context_epoch_session_id_session_id_fk\` FOREIGN KEY (\`session_id\`) REFERENCES \`session\`(\`id\`) ON DELETE CASCADE
         );
       `)

packages/core/src/event.ts

@@ -5,7 +5,7 @@ import { and, asc, eq, gt } from "drizzle-orm"
 import { Database } from "./database/database"
 import { EventSequenceTable, EventTable } from "./event/sql"
 import { Location } from "./location"
-import { externalID, type ExternalID, NonNegativeInt, withStatics } from "./schema"
+import { externalID, type ExternalID, withStatics } from "./schema"
 import { Identifier } from "./util/identifier"
 import { LayerNode } from "./effect/layer-node"
 import { isDeepStrictEqual } from "node:util"
@@ -19,16 +19,9 @@ export const ID = Schema.String.check(Schema.isStartsWith("evt_")).pipe(
 )
 export type ID = typeof ID.Type
 
-/**
- * Durable aggregate continuation position for embedded replay streams.
- * TODO: Decide whether a future HTTP / SDK surface should expose an opaque cursor instead.
- */
-export const Cursor = NonNegativeInt.pipe(Schema.brand("EventV2.Cursor"))
-export type Cursor = typeof Cursor.Type
-
 export type Definition<Type extends string = string, DataSchema extends Schema.Top = Schema.Top> = {
   readonly type: Type
-  readonly sync?: {
+  readonly durable?: {
     readonly version: number
     readonly aggregate: string
   }
@@ -41,20 +34,16 @@ export type Payload<D extends Definition = Definition> = {
   readonly id: ID
   readonly type: D["type"]
   readonly data: Data<D>
-  /** Durable aggregate order, populated while synchronized events are projected. */
-  readonly seq?: number
-  readonly version?: number
+  readonly durable?: {
+    readonly aggregateID: string
+    readonly seq: number
+    readonly version: number
+  }
   readonly location?: Location.Ref
   readonly metadata?: Record<string, unknown>
-  /** Internal replay marker for projectors that own non-replicated operational state. */
-  readonly replay?: boolean
 }
 
-export type Projector<D extends Definition = Definition> = (event: Payload<D>) => Effect.Effect<void>
-type AnyProjector = (event: Payload) => Effect.Effect<void>
-export type CommitGuard = (event: Payload) => Effect.Effect<void>
-export type Listener = (event: Payload) => Effect.Effect<void>
-export type Sync = (event: Payload) => Effect.Effect<void>
+export type Subscriber<D extends Definition = Definition> = (event: Payload<D>) => Effect.Effect<void>
 export type Unsubscribe = Effect.Effect<void>
 
 export type SerializedEvent = {
@@ -65,13 +54,8 @@ export type SerializedEvent = {
   readonly data: Record<string, unknown>
 }
 
-export type CursorEvent<E extends Payload = Payload> = {
-  readonly cursor: Cursor
-  readonly event: E
-}
-
-export class InvalidSyncEventError extends Schema.TaggedErrorClass<InvalidSyncEventError>()(
-  "EventV2.InvalidSyncEvent",
+export class InvalidDurableEventError extends Schema.TaggedErrorClass<InvalidDurableEventError>()(
+  "EventV2.InvalidDurableEvent",
   {
     type: Schema.String,
     message: Schema.String,
@@ -83,19 +67,11 @@ export function versionedType(type: string, version: number) {
 }
 
 export const registry = new Map<string, Definition>()
-type SyncDefinition = Definition & {
-  readonly sync: NonNullable<Definition["sync"]>
-  readonly encode: (data: unknown) => unknown
-  readonly decode: (data: unknown) => unknown
-}
-const syncRegistry = new Map<string, SyncDefinition>()
-
-// Synchronized events cross a JSON boundary, so their data schemas must encode and decode without services.
-const syncCodec = (definition: Definition) => definition.data as Schema.Codec<unknown, unknown, never, never>
+const durableRegistry = new Map<string, Definition>()
 
 export function define<const Type extends string, Fields extends Schema.Struct.Fields>(input: {
   readonly type: Type
-  readonly sync?: {
+  readonly durable?: {
     readonly version: number
     readonly aggregate: string
   }
@@ -106,28 +82,25 @@ export function define<const Type extends string, Fields extends Schema.Struct.F
     id: ID,
     metadata: Schema.optional(Schema.Record(Schema.String, Schema.Unknown)),
     type: Schema.Literal(input.type),
-    version: Schema.optional(Schema.Number),
+    durable: Schema.optional(Schema.Struct({ aggregateID: Schema.String, seq: Schema.Number, version: Schema.Number })),
     location: Schema.optional(Location.Ref),
     data: Data,
   }).annotate({ identifier: input.type })
 
   const definition = Object.assign(Payload, {
     type: input.type,
-    ...(input.sync === undefined ? {} : { sync: input.sync }),
+    ...(input.durable === undefined ? {} : { durable: input.durable }),
     data: Data,
   })
   const existing = registry.get(input.type)
-  if (input.sync === undefined || existing?.sync === undefined || input.sync.version >= existing.sync.version) {
+  if (
+    input.durable === undefined ||
+    existing?.durable === undefined ||
+    input.durable.version >= existing.durable.version
+  ) {
     registry.set(input.type, definition)
   }
-  if (input.sync)
-    syncRegistry.set(
-      versionedType(input.type, input.sync.version),
-      Object.assign(definition, {
-        encode: Schema.encodeUnknownSync(syncCodec(definition)),
-        decode: Schema.decodeUnknownSync(syncCodec(definition)),
-      }) as SyncDefinition,
-    )
+  if (input.durable) durableRegistry.set(versionedType(input.type, input.durable.version), definition)
   return definition as Schema.Schema<Payload<Definition<Type, Schema.Struct<Fields>>>> &
     Definition<Type, Schema.Struct<Fields>>
 }
@@ -140,7 +113,7 @@ export interface PublishOptions {
   readonly id?: ID
   readonly metadata?: Record<string, unknown>
   readonly location?: Location.Ref
-  /** Local operational projection committed atomically with a new synchronized event. Not replayed or serialized. */
+  /** Local operational projection committed atomically with a new durable event. Not replayed or serialized. */
   readonly commit?: (seq: number) => Effect.Effect<void>
 }
 
@@ -152,14 +125,10 @@ export interface Interface {
   ) => Effect.Effect<Payload<D>>
   readonly subscribe: <D extends Definition>(definition: D) => Stream.Stream<Payload<D>>
   readonly all: () => Stream.Stream<Payload>
-  readonly aggregateEvents: (input: {
-    readonly aggregateID: string
-    readonly after?: Cursor
-  }) => Stream.Stream<CursorEvent>
-  readonly sync: (handler: Sync) => Effect.Effect<Unsubscribe>
-  readonly listen: (listener: Listener) => Effect.Effect<Unsubscribe>
-  readonly beforeCommit: (guard: CommitGuard) => Effect.Effect<void>
-  readonly project: <D extends Definition>(definition: D, projector: Projector<D>) => Effect.Effect<void>
+  readonly durable: (input: { readonly aggregateID: string; readonly after?: number }) => Stream.Stream<Payload>
+  /** @deprecated Use `all()` and consume the returned stream. */
+  readonly listen: (listener: Subscriber) => Effect.Effect<Unsubscribe>
+  readonly project: <D extends Definition>(definition: D, projector: Subscriber<D>) => Effect.Effect<void>
   readonly replay: (
     event: SerializedEvent,
     options?: { readonly publish?: boolean; readonly ownerID?: string; readonly strictOwner?: boolean },
@@ -182,37 +151,37 @@ export const layerWith = (options?: LayerOptions) =>
   Layer.effect(
     Service,
     Effect.gen(function* () {
-      const all = yield* PubSub.unbounded<Payload>()
-      const synchronized = new Map<string, Set<PubSub.PubSub<void>>>()
-      const typed = new Map<string, PubSub.PubSub<Payload>>()
-      const projectors = new Map<string, AnyProjector[]>()
-      const commitGuards = new Array<CommitGuard>()
-      const listeners = new Array<Listener>()
-      const syncHandlers = new Array<Sync>()
+      const pubsub = {
+        all: yield* PubSub.unbounded<Payload>(),
+        durable: new Map<string, Set<PubSub.PubSub<void>>>(),
+        typed: new Map<string, PubSub.PubSub<Payload>>(),
+      }
+      const projectors = new Map<string, Subscriber[]>()
+      const listeners = new Array<Subscriber>()
       const { db } = yield* Database.Service
 
       const getOrCreate = (definition: Definition) =>
         Effect.gen(function* () {
-          const existing = typed.get(definition.type)
+          const existing = pubsub.typed.get(definition.type)
           if (existing) return existing
-          const pubsub = yield* PubSub.unbounded<Payload>()
-          typed.set(definition.type, pubsub)
-          return pubsub
+          const created = yield* PubSub.unbounded<Payload>()
+          pubsub.typed.set(definition.type, created)
+          return created
         })
 
       yield* Effect.addFinalizer(() =>
         Effect.gen(function* () {
-          yield* PubSub.shutdown(all)
+          yield* PubSub.shutdown(pubsub.all)
           yield* Effect.forEach(
-            synchronized.values(),
+            pubsub.durable.values(),
             (pubsubs) => Effect.forEach(pubsubs, PubSub.shutdown, { discard: true }),
             { discard: true },
           )
-          yield* Effect.forEach(typed.values(), PubSub.shutdown, { discard: true })
+          yield* Effect.forEach(pubsub.typed.values(), PubSub.shutdown, { discard: true })
         }),
       )
 
-      function commitSyncEvent(
+      function commitDurableEvent(
         event: Payload,
         input?: {
           readonly seq: number
@@ -224,28 +193,20 @@ export const layerWith = (options?: LayerOptions) =>
       ) {
         return Effect.gen(function* () {
           const definition = registry.get(event.type)
-          const sync = definition?.sync
-          if (sync) {
-            if (event.version !== sync.version) {
-              yield* Effect.die(
-                new InvalidSyncEventError({
-                  type: event.type,
-                  message: `Expected event version ${sync.version}, got ${event.version}`,
-                }),
-              )
-            }
-            const aggregateID = (event.data as Record<string, unknown>)[sync.aggregate]
+          const durable = definition?.durable
+          if (durable) {
+            const aggregateID = (event.data as Record<string, unknown>)[durable.aggregate]
             if (typeof aggregateID !== "string") {
               yield* Effect.die(
-                new InvalidSyncEventError({
+                new InvalidDurableEventError({
                   type: event.type,
-                  message: `Expected string aggregate field ${sync.aggregate}`,
+                  message: `Expected string aggregate field ${durable.aggregate}`,
                 }),
               )
             } else {
               if (input && input.aggregateID !== aggregateID) {
                 yield* Effect.die(
-                  new InvalidSyncEventError({
+                  new InvalidDurableEventError({
                     type: event.type,
                     message: `Aggregate mismatch: expected ${input.aggregateID}, got ${aggregateID}`,
                   }),
@@ -265,12 +226,12 @@ export const layerWith = (options?: LayerOptions) =>
                             .get()
                             .pipe(Effect.orDie)
                           const latest = row?.seq ?? -1
-                          const encoded = syncRegistry
-                            .get(versionedType(definition.type, sync.version))!
-                            .encode(event.data) as Record<string, unknown>
+                          const encoded = Schema.encodeUnknownSync(
+                            definition.data as Schema.Codec<unknown, unknown, never, never>,
+                          )(event.data) as Record<string, unknown>
                           if (input?.strictOwner && row?.ownerID && row.ownerID !== input.ownerID) {
                             yield* Effect.die(
-                              new InvalidSyncEventError({
+                              new InvalidDurableEventError({
                                 type: event.type,
                                 message: `Replay owner mismatch for aggregate ${aggregateID}: expected ${row.ownerID}, got ${input.ownerID ?? "none"}`,
                               }),
@@ -285,7 +246,7 @@ export const layerWith = (options?: LayerOptions) =>
                               .pipe(Effect.orDie)
                             if (
                               stored?.id === event.id &&
-                              stored.type === versionedType(definition.type, sync.version) &&
+                              stored.type === versionedType(definition.type, durable.version) &&
                               isDeepStrictEqual(stored.data, encoded)
                             ) {
                               if (input.ownerID && row?.ownerID == null) {
@@ -299,7 +260,7 @@ export const layerWith = (options?: LayerOptions) =>
                               return
                             }
                             yield* Effect.die(
-                              new InvalidSyncEventError({
+                              new InvalidDurableEventError({
                                 type: event.type,
                                 message: `Replay diverged at aggregate ${aggregateID} sequence ${input.seq}`,
                               }),
@@ -311,7 +272,7 @@ export const layerWith = (options?: LayerOptions) =>
                           const seq = input?.seq ?? latest + 1
                           if (input && seq !== latest + 1) {
                             yield* Effect.die(
-                              new InvalidSyncEventError({
+                              new InvalidDurableEventError({
                                 type: event.type,
                                 message: `Sequence mismatch for aggregate ${aggregateID}: expected ${latest + 1}, got ${seq}`,
                               }),
@@ -325,16 +286,17 @@ export const layerWith = (options?: LayerOptions) =>
                             .pipe(Effect.orDie)
                           if (stored)
                             yield* Effect.die(
-                              new InvalidSyncEventError({
+                              new InvalidDurableEventError({
                                 type: event.type,
                                 message: `Event ${event.id} already exists at aggregate ${stored.aggregateID} sequence ${stored.seq}`,
                               }),
                             )
-                          for (const guard of commitGuards) {
-                            yield* guard(event)
-                          }
+                          const committed = {
+                            ...event,
+                            durable: { aggregateID, seq, version: durable.version },
+                          } as Payload
                           for (const projector of list) {
-                            yield* projector({ ...event, seq } as Payload)
+                            yield* projector(committed)
                           }
                           if (commit) yield* commit(seq)
                           yield* db
@@ -356,7 +318,7 @@ export const layerWith = (options?: LayerOptions) =>
                                 id: event.id,
                                 aggregate_id: aggregateID,
                                 seq,
-                                type: versionedType(definition.type, sync.version),
+                                type: versionedType(definition.type, durable.version),
                                 data: encoded,
                               },
                             ])
@@ -369,8 +331,8 @@ export const layerWith = (options?: LayerOptions) =>
                     .pipe(Effect.orDie)
                   if (committed) {
                     yield* Effect.forEach(
-                      synchronized.get(committed.aggregateID) ?? [],
-                      (pubsub) => PubSub.publish(pubsub, undefined),
+                      pubsub.durable.get(committed.aggregateID) ?? [],
+                      (wake) => PubSub.publish(wake, undefined),
                       { discard: true },
                     )
                   }
@@ -384,19 +346,25 @@ export const layerWith = (options?: LayerOptions) =>
 
       function publishEvent<D extends Definition>(event: Payload<D>, commit?: PublishOptions["commit"]) {
         return Effect.gen(function* () {
-          const durable = registry.get(event.type)?.sync !== undefined
-          if (!durable && commit)
+          const definition = registry.get(event.type)
+          if (!definition?.durable && commit)
             return yield* Effect.die(
-              new InvalidSyncEventError({
+              new InvalidDurableEventError({
                 type: event.type,
-                message: "Local commit hooks require a synchronized event",
+                message: "Local commit hooks require a durable event",
               }),
             )
-          if (durable) {
-            const committed = yield* commitSyncEvent(event as Payload, undefined, commit)
+          if (definition?.durable) {
+            const committed = yield* commitDurableEvent(event as Payload, undefined, commit)
             if (committed) {
-              event = { ...event, seq: committed.seq }
-              yield* Effect.forEach(syncHandlers, (sync) => observe(event as Payload, "sync", sync), { discard: true })
+              event = {
+                ...event,
+                durable: {
+                  aggregateID: committed.aggregateID,
+                  seq: committed.seq,
+                  version: definition.durable.version,
+                },
+              }
               yield* notify(event as Payload, true)
               return event
             }
@@ -406,12 +374,11 @@ export const layerWith = (options?: LayerOptions) =>
         })
       }
 
-      const observe = (event: Payload, kind: "sync" | "listener", observer: (event: Payload) => Effect.Effect<void>) =>
+      const observe = (event: Payload, observer: (event: Payload) => Effect.Effect<void>) =>
         Effect.suspend(() => observer(event)).pipe(
           Effect.catchCauseIf(
             (cause) => !Cause.hasInterrupts(cause),
-            (cause) =>
-              Effect.logError("Event observer failed", { eventID: event.id, eventType: event.type, kind, cause }),
+            (cause) => Effect.logError("Event listener failed", { eventID: event.id, eventType: event.type, cause }),
           ),
         )
 
@@ -419,12 +386,12 @@ export const layerWith = (options?: LayerOptions) =>
         return Effect.gen(function* () {
           yield* Effect.forEach(
             listeners,
-            (listener) => (isolateListeners ? observe(event, "listener", listener) : listener(event)),
+            (listener) => (isolateListeners ? observe(event, listener) : listener(event)),
             { discard: true },
           )
-          const pubsub = typed.get(event.type)
-          if (pubsub) yield* PubSub.publish(pubsub, event)
-          yield* PubSub.publish(all, event)
+          const typed = pubsub.typed.get(event.type)
+          if (typed) yield* PubSub.publish(typed, event)
+          yield* PubSub.publish(pubsub.all, event)
         })
       }
 
@@ -441,7 +408,6 @@ export const layerWith = (options?: LayerOptions) =>
               id: options?.id ?? ID.create(),
               ...(options?.metadata ? { metadata: options.metadata } : {}),
               type: definition.type,
-              ...(definition.sync === undefined ? {} : { version: definition.sync.version }),
               ...(location ? { location } : {}),
               data,
             } as Payload<D>,
@@ -455,27 +421,37 @@ export const layerWith = (options?: LayerOptions) =>
         options?: { readonly publish?: boolean; readonly ownerID?: string; readonly strictOwner?: boolean },
       ) {
         return Effect.gen(function* () {
-          const definition = syncRegistry.get(event.type)
-          if (!definition) {
+          const definition = durableRegistry.get(event.type)
+          if (!definition?.durable) {
             yield* Effect.die(
-              new InvalidSyncEventError({ type: event.type, message: `Unknown sync event type ${event.type}` }),
+              new InvalidDurableEventError({ type: event.type, message: `Unknown durable event type ${event.type}` }),
             )
           } else {
             const payload = {
               id: event.id,
               type: definition.type,
-              version: definition.sync.version,
-              data: definition.decode(event.data),
-              replay: true,
+              data: Schema.decodeUnknownSync(definition.data as Schema.Codec<unknown, unknown, never, never>)(
+                event.data,
+              ),
             } as Payload
-            const committed = yield* commitSyncEvent(payload, {
+            const committed = yield* commitDurableEvent(payload, {
               seq: event.seq,
               aggregateID: event.aggregateID,
               ownerID: options?.ownerID,
               strictOwner: options?.strictOwner,
             })
             if (committed && options?.publish) {
-              yield* notify({ ...payload, seq: committed.seq }, true)
+              yield* notify(
+                {
+                  ...payload,
+                  durable: {
+                    aggregateID: committed.aggregateID,
+                    seq: committed.seq,
+                    version: definition.durable.version,
+                  },
+                },
+                true,
+              )
             }
           }
         })
@@ -490,7 +466,7 @@ export const layerWith = (options?: LayerOptions) =>
           if (!source) return undefined
           if (events.some((event) => event.aggregateID !== source)) {
             yield* Effect.die(
-              new InvalidSyncEventError({
+              new InvalidDurableEventError({
                 type: events[0]?.type ?? "unknown",
                 message: "Replay events must belong to the same aggregate",
               }),
@@ -501,7 +477,7 @@ export const layerWith = (options?: LayerOptions) =>
             const seq = start + index
             if (event.seq !== seq) {
               yield* Effect.die(
-                new InvalidSyncEventError({
+                new InvalidDurableEventError({
                   type: event.type,
                   message: `Replay sequence mismatch at index ${index}: expected ${seq}, got ${event.seq}`,
                 }),
@@ -540,22 +516,18 @@ export const layerWith = (options?: LayerOptions) =>
           Stream.map((event) => event as Payload<D>),
         )
 
-      const streamAll = (): Stream.Stream<Payload> => Stream.fromPubSub(all)
+      const streamAll = (): Stream.Stream<Payload> => Stream.fromPubSub(pubsub.all)
 
-      const decodeSerializedEvent = (event: SerializedEvent): CursorEvent => {
-        const definition = syncRegistry.get(event.type)
-        if (!definition) {
-          throw new InvalidSyncEventError({ type: event.type, message: `Unknown sync event type ${event.type}` })
+      const decodeSerializedEvent = (event: SerializedEvent): Payload => {
+        const definition = durableRegistry.get(event.type)
+        if (!definition?.durable) {
+          throw new InvalidDurableEventError({ type: event.type, message: `Unknown durable event type ${event.type}` })
         }
         return {
-          cursor: Cursor.make(event.seq),
-          event: {
-            id: event.id,
-            type: definition.type,
-            version: definition.sync.version,
-            seq: event.seq,
-            data: definition.decode(event.data),
-          },
+          id: event.id,
+          type: definition.type,
+          durable: { aggregateID: event.aggregateID, seq: event.seq, version: definition.durable.version },
+          data: Schema.decodeUnknownSync(definition.data as Schema.Codec<unknown, unknown, never, never>)(event.data),
         }
       }
 
@@ -583,43 +555,40 @@ export const layerWith = (options?: LayerOptions) =>
           ),
         )
 
-      const subscribeSynchronized = (aggregateID: string) =>
+      const subscribeDurable = (aggregateID: string) =>
         Effect.gen(function* () {
-          const pubsub = yield* PubSub.sliding<void>(1)
-          const subscription = yield* PubSub.subscribe(pubsub)
+          const wake = yield* PubSub.sliding<void>(1)
+          const subscription = yield* PubSub.subscribe(wake)
           yield* Effect.acquireRelease(
             Effect.sync(() => {
-              const pubsubs = synchronized.get(aggregateID) ?? new Set()
-              pubsubs.add(pubsub)
-              synchronized.set(aggregateID, pubsubs)
+              const wakes = pubsub.durable.get(aggregateID) ?? new Set()
+              wakes.add(wake)
+              pubsub.durable.set(aggregateID, wakes)
             }),
             () =>
               Effect.sync(() => {
-                const pubsubs = synchronized.get(aggregateID)
-                pubsubs?.delete(pubsub)
-                if (pubsubs?.size === 0) synchronized.delete(aggregateID)
-              }).pipe(Effect.andThen(PubSub.shutdown(pubsub))),
+                const wakes = pubsub.durable.get(aggregateID)
+                wakes?.delete(wake)
+                if (wakes?.size === 0) pubsub.durable.delete(aggregateID)
+              }).pipe(Effect.andThen(PubSub.shutdown(wake))),
           )
           return subscription
         })
 
-      const streamEvents = (input: {
-        readonly aggregateID: string
-        readonly after?: Cursor
-      }): Stream.Stream<CursorEvent> =>
+      const durable = (input: { readonly aggregateID: string; readonly after?: number }): Stream.Stream<Payload> =>
         Stream.unwrap(
           Effect.gen(function* () {
-            const synchronized = yield* subscribeSynchronized(input.aggregateID)
-            let cursor = input.after ?? -1
-            const read = Effect.suspend(() => readAfter(input.aggregateID, cursor)).pipe(
+            const wakes = yield* subscribeDurable(input.aggregateID)
+            let sequence = input.after ?? -1
+            const read = Effect.suspend(() => readAfter(input.aggregateID, sequence)).pipe(
               Effect.tap((events) =>
                 Effect.sync(() => {
-                  cursor = events.at(-1)?.cursor ?? cursor
+                  sequence = events.at(-1)?.durable?.seq ?? sequence
                 }),
               ),
             )
             const historical = yield* read
-            const live = Stream.fromSubscription(synchronized).pipe(
+            const live = Stream.fromSubscription(wakes).pipe(
               Stream.mapEffect(() => read),
               Stream.flattenIterable,
             )
@@ -627,7 +596,7 @@ export const layerWith = (options?: LayerOptions) =>
           }),
         )
 
-      const listen = (listener: Listener): Effect.Effect<Unsubscribe> =>
+      const listen = (listener: Subscriber): Effect.Effect<Unsubscribe> =>
         Effect.sync(() => {
           listeners.push(listener)
           return Effect.sync(() => {
@@ -636,21 +605,7 @@ export const layerWith = (options?: LayerOptions) =>
           })
         })
 
-      const sync = (handler: Sync): Effect.Effect<Unsubscribe> =>
-        Effect.sync(() => {
-          syncHandlers.push(handler)
-          return Effect.sync(() => {
-            const index = syncHandlers.indexOf(handler)
-            if (index >= 0) syncHandlers.splice(index, 1)
-          })
-        })
-
-      const beforeCommit = (guard: CommitGuard): Effect.Effect<void> =>
-        Effect.sync(() => {
-          commitGuards.push(guard)
-        })
-
-      const project = <D extends Definition>(definition: D, projector: Projector<D>): Effect.Effect<void> =>
+      const project = <D extends Definition>(definition: D, projector: Subscriber<D>): Effect.Effect<void> =>
         Effect.sync(() => {
           const list = projectors.get(definition.type) ?? []
           list.push((event) => projector(event as Payload<D>))
@@ -661,10 +616,8 @@ export const layerWith = (options?: LayerOptions) =>
         publish,
         subscribe,
         all: streamAll,
-        aggregateEvents: streamEvents,
-        sync,
+        durable,
         listen,
-        beforeCommit,
         project,
         replay,
         replayAll,

packages/core/src/filesystem.ts

@@ -123,6 +123,6 @@ const baseLayer = Layer.effect(
   }),
 )
 
-export const layer = baseLayer.pipe(Layer.provide(FileSystemSearch.defaultLayer), Layer.provide(FSUtil.defaultLayer))
+export const layer = baseLayer.pipe(Layer.provide(FileSystemSearch.locationLayer), Layer.provide(FSUtil.defaultLayer))
 
 export const locationLayer = layer

packages/core/src/filesystem/search.ts

@@ -232,6 +232,6 @@ export const fffLayer = Layer.effect(
   }),
 )
 
-export const defaultLayer = Layer.unwrap(
+export const locationLayer = Layer.unwrap(
   Effect.sync(() => (Flag.OPENCODE_DISABLE_FFF || !Fff.available() ? ripgrepLayer : fffLayer)),
 )

packages/core/src/integration.ts

@@ -108,11 +108,11 @@ export type OAuthAuthorization = {
 } & (
   | {
       readonly mode: "auto"
-      readonly callback: Effect.Effect<Credential.Info, unknown>
+      readonly callback: Effect.Effect<Credential.Value, unknown>
     }
   | {
       readonly mode: "code"
-      readonly callback: (code: string) => Effect.Effect<Credential.Info, unknown>
+      readonly callback: (code: string) => Effect.Effect<Credential.Value, unknown>
     }
 )
 
@@ -214,8 +214,6 @@ export interface Interface extends State.Transformable<Draft> {
   /** Returns all integrations with their methods and current connections. */
   readonly list: () => Effect.Effect<Info[]>
   readonly connection: {
-    /** Returns active connections for every registered or credential-backed integration. */
-    readonly list: () => Effect.Effect<Map<ID, IntegrationConnection.Info>>
     /** Returns the active connection for one integration. */
     readonly forIntegration: (id: ID) => Effect.Effect<IntegrationConnection.Info | undefined>
     /** Runs a key method and stores the resulting credential. */
@@ -241,7 +239,7 @@ export interface Interface extends State.Transformable<Draft> {
     /** Updates a stored credential exposed as a connection. */
     readonly update: (
       credentialID: Credential.ID,
-      updates: Partial<Pick<Credential.Stored, "label">>,
+      updates: Partial<Pick<Credential.Info, "label">>,
     ) => Effect.Effect<void>
     /** Removes a stored credential connection. */
     readonly remove: (credentialID: Credential.ID) => Effect.Effect<void>
@@ -353,39 +351,27 @@ export const locationLayer = Layer.effect(
       finalize: () => events.publish(Event.Updated, {}).pipe(Effect.asVoid),
     })
 
-    const connections = (entry: Entry, saved: readonly Credential.Stored[]): IntegrationConnection.Info[] => {
-      const connected = saved.map((credential) => ({
-        type: "credential" as const,
-        id: credential.id,
-        label: credential.label,
-      }))
-      const detected = entry.methods
+    const resolveConnections = (entry: Entry | undefined, saved: readonly Credential.Info[]) => {
+      const credentials = saved
+        .map((credential) => ({
+          type: "credential" as const,
+          id: credential.id,
+          label: credential.label,
+        }))
+        .toReversed()
+      const env = (entry?.methods ?? [])
         .filter((method) => method.type === "env")
         .flatMap((method) => method.names.filter((name) => process.env[name]))
         .map((name) => ({ type: "env" as const, name }))
-      return [...connected, ...detected]
+      return [...credentials, ...env]
     }
 
-    const activeConnection = (
-      entry: Entry | undefined,
-      saved: readonly Credential.Stored[],
-    ): IntegrationConnection.Info | undefined => {
-      const credential = saved.at(-1)
-      if (credential) return { type: "credential", id: credential.id, label: credential.label }
-      if (!entry) return
-      const name = entry.methods
-        .filter((method) => method.type === "env")
-        .flatMap((method) => method.names)
-        .find((name) => process.env[name])
-      if (name) return { type: "env", name }
-    }
-
-    const project = (entry: Entry, saved: readonly Credential.Stored[]) =>
+    const project = (entry: Entry, connections: IntegrationConnection.Info[]) =>
       new Info({
         id: entry.ref.id,
         name: entry.ref.name,
         methods: entry.methods,
-        connections: connections(entry, saved),
+        connections,
       })
 
     const authorize = <A, E, R>(effect: Effect.Effect<A, E, R>) =>
@@ -399,7 +385,7 @@ export const locationLayer = Layer.effect(
       return error instanceof Error ? error.message : String(error)
     }
 
-    const settle = Effect.fnUntraced(function* (attemptID: AttemptID, exit: Exit.Exit<Credential.Info, unknown>) {
+    const settle = Effect.fnUntraced(function* (attemptID: AttemptID, exit: Exit.Exit<Credential.Value, unknown>) {
       const now = yield* Clock.currentTimeMillis
       const result = yield* SynchronizedRef.modify(attempts, (current) => {
         const attempt = current.get(attemptID)
@@ -450,28 +436,18 @@ export const locationLayer = Layer.effect(
       get: Effect.fn("Integration.get")(function* (id) {
         const entry = state.get().integrations.get(id)
         if (!entry) return undefined
-        return project(entry, yield* credentials.list(id))
+        return project(entry, resolveConnections(entry, yield* credentials.list(id)))
       }),
       list: Effect.fn("Integration.list")(function* () {
-        return (yield* Effect.forEach(state.get().integrations.values(), (entry) =>
-          Effect.gen(function* () {
-            return project(entry, yield* credentials.list(entry.ref.id))
-          }),
-        )).toSorted((a, b) => a.name.localeCompare(b.name))
+        const saved = Map.groupBy(yield* credentials.all(), (credential) => credential.integrationID)
+        return Array.from(state.get().integrations.values(), (entry) =>
+          project(entry, resolveConnections(entry, saved.get(entry.ref.id) ?? [])),
+        ).toSorted((a, b) => a.name.localeCompare(b.name))
       }),
       connection: {
-        list: Effect.fn("Integration.connection.list")(function* () {
-          const saved = Map.groupBy(yield* credentials.all(), (credential) => credential.integrationID)
-          return new Map(
-            new Set([...state.get().integrations.keys(), ...saved.keys()]).values().flatMap((id) => {
-              const connection = activeConnection(state.get().integrations.get(id), saved.get(id) ?? [])
-              return connection ? [[id, connection] as const] : []
-            }),
-          )
-        }),
         forIntegration: Effect.fn("Integration.connection.forIntegration")(function* (id) {
           const entry = state.get().integrations.get(id)
-          return activeConnection(entry, yield* credentials.list(id))
+          return resolveConnections(entry, yield* credentials.list(id))[0]
         }),
         key: Effect.fn("Integration.connection.key")(function* (input) {
           const method = state

packages/core/src/plugin.ts

@@ -103,8 +103,16 @@ export const layer = Layer.effect(
       }
     }[keyof Hooks][] = []
     const events = yield* EventV2.Service
-    const scope = yield* Scope.Scope
     const locks = KeyedMutex.makeUnsafe<ID>()
+    const scope = yield* Scope.make()
+
+    // One registry-owned scope lets shutdown remove every plugin transform in one batch.
+    yield* Effect.addFinalizer((exit) =>
+      Effect.gen(function* () {
+        hooks = []
+        yield* State.batch(Scope.close(scope, exit))
+      }),
+    )
 
     const svc = Service.of({
       add: Effect.fn("Plugin.add")(function* (input) {
@@ -112,7 +120,7 @@ export const layer = Layer.effect(
         yield* locks.withLock(id)(
           Effect.gen(function* () {
             const existing = hooks.find((item) => item.id === id)
-            if (existing) yield* Scope.close(existing.scope, Exit.void).pipe(Effect.ignore)
+            if (existing) yield* State.batch(Scope.close(existing.scope, Exit.void)).pipe(Effect.ignore)
             const childScope = yield* Scope.fork(scope)
             const result = yield* input.effect.pipe(
               Scope.provide(childScope),
@@ -181,7 +189,7 @@ export const layer = Layer.effect(
           Effect.gen(function* () {
             const existing = hooks.find((item) => item.id === id)
             hooks = hooks.filter((item) => item.id !== id)
-            if (existing) yield* Scope.close(existing.scope, Exit.void).pipe(Effect.ignore)
+            if (existing) yield* State.batch(Scope.close(existing.scope, Exit.void)).pipe(Effect.ignore)
           }),
         )
       }),

packages/core/src/provider.ts

@@ -38,8 +38,7 @@ export const Native = Schema.Struct({
 export const Api = Schema.Union([AISDK, Native]).pipe(Schema.toTaggedUnion("type"))
 export type Api = typeof Api.Type
 export type MutableApi<T extends Api = Api> = T extends Api
-  ? Omit<Types.DeepMutable<T>, "settings"> &
-      (undefined extends T["settings"] ? { settings?: any } : { settings: any })
+  ? Omit<Types.DeepMutable<T>, "settings"> & (undefined extends T["settings"] ? { settings?: any } : { settings: any })
   : never
 
 export const Request = Schema.Struct({

packages/core/src/public/opencode.ts

@@ -1,11 +1,9 @@
 export * as OpenCode from "./opencode"
 
 import { Context, Effect, Layer } from "effect"
-import { Catalog } from "../catalog"
 import { Database } from "../database/database"
 import { EventV2 } from "../event"
 import { LocationServiceMap } from "../location-layer"
-import { PluginBoot } from "../plugin/boot"
 import { ProjectV2 } from "../project"
 import { SessionV2 } from "../session"
 import * as SessionExecutionLocal from "../session/execution/local"
@@ -23,69 +21,22 @@ export interface Interface {
 /** Intentional public native API for Effect applications embedding OpenCode. */
 export class Service extends Context.Service<Service, Interface>()("@opencode/public/OpenCode") {}
 
-class SessionModelValidation extends Context.Service<
-  SessionModelValidation,
-  {
-    readonly validate: (
-      input: Session.SwitchModelInput & { readonly location: Session.Info["location"] },
-    ) => Effect.Effect<void, Session.ModelUnavailableError | Session.VariantUnavailableError>
-  }
->()("@opencode/public/OpenCode/SessionModelValidation") {}
-
-const ApplicationToolsLayer = ApplicationTools.layer
-const LocationServicesLayer = LocationServiceMap.layer.pipe(Layer.provide(ApplicationToolsLayer))
-const SessionModelValidationLayer = Layer.effect(
-  SessionModelValidation,
-  Effect.gen(function* () {
-    const locations = yield* LocationServiceMap
-    return SessionModelValidation.of({
-      validate: Effect.fn("OpenCode.sessions.validateModel")(function* (input) {
-        yield* Effect.gen(function* () {
-          yield* (yield* PluginBoot.Service).wait()
-          const catalog = yield* Catalog.Service
-          const model = (yield* catalog.model.available()).find(
-            (model) => model.providerID === input.model.providerID && model.id === input.model.id,
-          )
-          if (!model)
-            return yield* new Session.ModelUnavailableError({
-              providerID: input.model.providerID,
-              modelID: input.model.id,
-            })
-          if (
-            input.model.variant !== undefined &&
-            input.model.variant !== "default" &&
-            !model.variants.some((variant) => variant.id === input.model.variant)
-          )
-            return yield* new Session.VariantUnavailableError({
-              providerID: input.model.providerID,
-              modelID: input.model.id,
-              variant: input.model.variant,
-            })
-        }).pipe(Effect.provide(locations.get(input.location)))
-      }),
-    })
-  }),
+const SessionsLayer = SessionV2.layer.pipe(
+  Layer.provide(SessionProjector.layer),
+  Layer.provide(SessionExecutionLocal.layer),
+  Layer.provide(SessionStore.layer),
+  Layer.provide(EventV2.layer),
+  Layer.provide(Database.defaultLayer),
+  Layer.provide(ProjectV2.defaultLayer),
+  Layer.provide(LocationServiceMap.layer.pipe(Layer.provide(ApplicationTools.layer))),
+  Layer.orDie,
 )
-
-const SessionsLayer = Layer.merge(
-  SessionV2.layer.pipe(
-    Layer.provide(SessionProjector.layer),
-    Layer.provide(SessionExecutionLocal.layer),
-    Layer.provide(SessionStore.layer),
-    Layer.provide(EventV2.layer),
-    Layer.provide(Database.defaultLayer),
-    Layer.provide(ProjectV2.defaultLayer),
-    Layer.orDie,
-  ),
-  SessionModelValidationLayer,
-).pipe(Layer.provide(LocationServicesLayer))
 // TODO: Accept explicit storage so tests and embeddings can select disposable or application-owned persistence.
 export const layer = Layer.effect(
   Service,
   Effect.gen(function* () {
     const sessions = yield* SessionV2.Service
     const tools = yield* ApplicationTools.Service
-    const validation = yield* SessionModelValidation
     return Service.of({
       tools: { register: tools.register },
       sessions: {
@@ -98,11 +49,7 @@ export const layer = Layer.effect(
           }),
         get: sessions.get,
         list: sessions.list,
-        switchModel: Effect.fn("OpenCode.sessions.switchModel")(function* (input) {
-          const session = yield* sessions.get(input.sessionID)
-          yield* validation.validate({ ...input, location: session.location })
-          yield* sessions.switchModel(input)
-        }),
+        switchModel: sessions.switchModel,
         interrupt: sessions.interrupt,
         prompt: (input) =>
           sessions.prompt({
@@ -124,6 +71,6 @@ export const layer = Layer.effect(
       },
     })
   }),
-).pipe(Layer.provide(Layer.merge(ApplicationToolsLayer, SessionsLayer)))
+).pipe(Layer.provide(Layer.merge(ApplicationTools.layer, SessionsLayer)))
 
 // TODO: Add OpenCode.create(...) as the Promise facade over the same native API semantics.

packages/core/src/public/session.ts

@@ -1,8 +1,6 @@
 export * as Session from "./session"
 
-import { Effect, Schema, Stream } from "effect"
-import { EventV2 } from "../event"
-import { ModelV2 } from "../model"
+import { Effect, Stream } from "effect"
 import { SessionV2 } from "../session"
 import { MessageDecodeError } from "../session/error"
 import { SessionEvent } from "../session/event"
@@ -34,9 +32,7 @@ export type Delivery = SessionInput.Delivery
 export const ListInput = SessionV2.ListInput
 export type ListInput = SessionV2.ListInput
 
-export const EventCursor = EventV2.Cursor
-export type EventCursor = EventV2.Cursor
-export type Event = EventV2.CursorEvent<SessionEvent.DurableEvent>
+export type Event = SessionEvent.DurableEvent
 
 export const NotFoundError = SessionV2.NotFoundError
 export type NotFoundError = SessionV2.NotFoundError
@@ -44,23 +40,6 @@ export type NotFoundError = SessionV2.NotFoundError
 export const PromptConflictError = SessionV2.PromptConflictError
 export type PromptConflictError = SessionV2.PromptConflictError
 
-export class ModelUnavailableError extends Schema.TaggedErrorClass<ModelUnavailableError>()(
-  "Session.ModelUnavailableError",
-  {
-    providerID: Model.Ref.fields.providerID,
-    modelID: Model.Ref.fields.id,
-  },
-) {}
-
-export class VariantUnavailableError extends Schema.TaggedErrorClass<VariantUnavailableError>()(
-  "Session.VariantUnavailableError",
-  {
-    providerID: Model.Ref.fields.providerID,
-    modelID: Model.Ref.fields.id,
-    variant: ModelV2.VariantID,
-  },
-) {}
-
 export { MessageDecodeError }
 
 export interface CreateInput {
@@ -99,7 +78,7 @@ export interface MessageInput {
 
 export interface EventsInput {
   readonly sessionID: ID
-  readonly after?: EventCursor
+  readonly after?: number
 }
 
 export interface Interface {
@@ -107,9 +86,7 @@ export interface Interface {
   readonly get: (sessionID: ID) => Effect.Effect<Info, NotFoundError>
   readonly list: (input?: ListInput) => Effect.Effect<Info[]>
   readonly prompt: (input: PromptInput) => Effect.Effect<Admission, NotFoundError | PromptConflictError>
-  readonly switchModel: (
-    input: SwitchModelInput,
-  ) => Effect.Effect<void, NotFoundError | ModelUnavailableError | VariantUnavailableError>
+  readonly switchModel: (input: SwitchModelInput) => Effect.Effect<void, NotFoundError>
   /** Interrupt the active V2 execution chain for one Session on this process. Interrupting an idle or missing Session is a no-op. */
   readonly interrupt: (sessionID: ID) => Effect.Effect<void>
   readonly messages: (input: MessagesInput) => Effect.Effect<Message[], NotFoundError | MessageDecodeError>

packages/core/src/session.ts

@@ -1,7 +1,7 @@
 export * as SessionV2 from "./session"
 export * from "./session/schema"
 
-import { Cause, DateTime, Effect, Layer, Schema, Context, Stream } from "effect"
+import { DateTime, Effect, Layer, Schema, Context, Stream } from "effect"
 import { and, asc, desc, eq, gt, like, lt, or, type SQL } from "drizzle-orm"
 import { ProjectV2 } from "./project"
 import { WorkspaceV2 } from "./workspace"
@@ -25,7 +25,6 @@ import { fromRow } from "./session/info"
 import { SessionRunner } from "./session/runner/index"
 import { SessionStore } from "./session/store"
 import { SessionExecution } from "./session/execution"
-import { logFailure } from "./session/logging"
 import { MessageDecodeError } from "./session/error"
 import { SessionEvent } from "./session/event"
 import { SessionInput } from "./session/input"
@@ -124,12 +123,9 @@ export interface Interface {
   ) => Effect.Effect<SessionMessage.Message[], NotFoundError | MessageDecodeError>
   readonly events: (input: {
     sessionID: SessionSchema.ID
-    after?: EventV2.Cursor
-  }) => Stream.Stream<EventV2.CursorEvent<SessionEvent.DurableEvent>, NotFoundError>
-  readonly switchAgent: (input: {
-    sessionID: SessionSchema.ID
-    agent: string
-  }) => Effect.Effect<void, OperationUnavailableError>
+    after?: number
+  }) => Stream.Stream<SessionEvent.DurableEvent, NotFoundError>
+  readonly switchAgent: (input: { sessionID: SessionSchema.ID; agent: string }) => Effect.Effect<void, NotFoundError>
   readonly switchModel: (input: {
     sessionID: SessionSchema.ID
     model: ModelV2.Ref
@@ -171,20 +167,6 @@ export const layer = Layer.effect(
     const store = yield* SessionStore.Service
     const decodeMessage = Schema.decodeUnknownEffect(SessionMessage.Message)
     const isDurableSessionEvent = Schema.is(SessionEvent.Durable)
-    const scope = yield* Effect.scope
-
-    const enqueueWake = (admitted: SessionInput.Admitted) =>
-      execution.wake(admitted.sessionID, admitted.admittedSeq).pipe(
-        Effect.tapCause((cause) =>
-          Cause.hasInterruptsOnly(cause)
-            ? Effect.void
-            : logFailure("Failed to wake Session", admitted.sessionID, cause),
-        ),
-        Effect.ignore,
-        Effect.forkIn(scope, { startImmediately: true }),
-        Effect.asVoid,
-      )
-
     const decode = (row: typeof SessionMessageTable.$inferSelect) =>
       decodeMessage({ ...row.data, id: row.id, type: row.type }).pipe(
         Effect.mapError(
@@ -339,20 +321,12 @@ export const layer = Layer.effect(
         Stream.unwrap(
           result
             .get(input.sessionID)
-            .pipe(Effect.as(events.aggregateEvents({ aggregateID: input.sessionID, after: input.after }))),
-        ).pipe(
-          Stream.filter((event): event is EventV2.CursorEvent<SessionEvent.DurableEvent> =>
-            isDurableSessionEvent(event.event),
-          ),
-        ),
+            .pipe(Effect.as(events.durable({ aggregateID: input.sessionID, after: input.after }))),
+        ).pipe(Stream.filter((event): event is SessionEvent.DurableEvent => isDurableSessionEvent(event))),
       prompt: Effect.fn("V2Session.prompt")((input) =>
         Effect.uninterruptible(
           Effect.gen(function* () {
             yield* result.get(input.sessionID)
-            const returnPrompt = Effect.fnUntraced(function* (admitted: SessionInput.Admitted) {
-              if (input.resume !== false) yield* enqueueWake(admitted)
-              return admitted
-            }, Effect.uninterruptible)
             const messageID = input.id ?? SessionMessage.ID.create()
             const delivery = input.delivery ?? "steer"
             const expected = { sessionID: input.sessionID, messageID, prompt: input.prompt, delivery }
@@ -370,7 +344,8 @@ export const layer = Layer.effect(
             )
             if (!SessionInput.equivalent(admitted, expected))
               return yield* new PromptConflictError({ sessionID: input.sessionID, messageID })
-            return yield* returnPrompt(admitted)
+            if (input.resume !== false) yield* execution.wake(admitted.sessionID)
+            return admitted
           }),
         ),
       ),
@@ -380,8 +355,14 @@ export const layer = Layer.effect(
       skill: Effect.fn("V2Session.skill")(function* () {
         return yield* new OperationUnavailableError({ operation: "skill" })
       }),
-      switchAgent: Effect.fn("V2Session.switchAgent")(function* () {
-        return yield* new OperationUnavailableError({ operation: "switchAgent" })
+      switchAgent: Effect.fn("V2Session.switchAgent")(function* (input) {
+        yield* result.get(input.sessionID)
+        yield* events.publish(SessionEvent.AgentSwitched, {
+          sessionID: input.sessionID,
+          messageID: SessionMessage.ID.create(),
+          timestamp: yield* DateTime.now,
+          agent: input.agent,
+        })
       }),
       switchModel: Effect.fn("V2Session.switchModel")(function* (input) {
         yield* result.get(input.sessionID)
@@ -405,19 +386,7 @@ export const layer = Layer.effect(
         yield* execution.resume(sessionID)
       }),
       interrupt: Effect.fn("V2Session.interrupt")((sessionID) =>
-        Effect.uninterruptible(
-          Effect.gen(function* () {
-            const session = yield* store.get(sessionID)
-            if (!session) return yield* execution.interrupt(sessionID)
-            const event = yield* events.publish(SessionEvent.InterruptRequested, {
-              sessionID,
-              timestamp: yield* DateTime.now,
-            })
-            if (event.seq === undefined)
-              return yield* Effect.die("Interrupt request event is missing aggregate sequence")
-            yield* execution.interrupt(sessionID, event.seq)
-          }),
-        ),
+        Effect.uninterruptible(execution.interrupt(sessionID)),
       ),
     })
 

packages/core/src/session/context-epoch.ts

@@ -1,54 +1,31 @@
 export * as SessionContextEpoch from "./context-epoch"
 
-import { and, eq, isNull, lt, or, sql } from "drizzle-orm"
+import { eq } from "drizzle-orm"
 import { DateTime, Effect, Schema } from "effect"
-import { AgentV2 } from "../agent"
 import type { Database } from "../database/database"
 import { EventV2 } from "../event"
-import { Location } from "../location"
 import { SystemContext } from "../system-context/index"
 import { ContextSnapshotDecodeError } from "./error"
 import { SessionEvent } from "./event"
+import { SessionHistory } from "./history"
 import { SessionInput } from "./input"
 import { SessionMessageID } from "./message-id"
 import { SessionSchema } from "./schema"
-import { SessionContextEpochTable, SessionTable } from "./sql"
+import { SessionContextEpochTable } from "./sql"
 
 type DatabaseService = Database.Interface["db"]
 
-class RevisionMismatch extends Error {}
-class LocationMismatch extends Error {}
-export class AgentMismatch extends Error {}
-export class AgentReplacementBlocked extends Schema.TaggedErrorClass<AgentReplacementBlocked>()(
-  "SessionContextEpoch.AgentReplacementBlocked",
-  { sessionID: SessionSchema.ID, previous: AgentV2.ID, current: AgentV2.ID },
-) {}
-
-const retryRevisionMismatch = <A, E>(attempt: () => Effect.Effect<A, E>): Effect.Effect<A, E> =>
-  attempt().pipe(
-    Effect.catchDefect((defect) =>
-      defect instanceof RevisionMismatch
-        ? Effect.yieldNow.pipe(Effect.andThen(retryRevisionMismatch(attempt)))
-        : Effect.die(defect),
-    ),
-  )
-
 interface Prepared {
   readonly baseline: string
   readonly baselineSeq: number
-  readonly revision: number
 }
 
 export function initialize(
   db: DatabaseService,
   context: Effect.Effect<SystemContext.SystemContext>,
   sessionID: SessionSchema.ID,
-  location: Location.Ref,
-  agent: AgentV2.ID,
 ): Effect.Effect<Prepared | undefined, SystemContext.InitializationBlocked> {
-  return retryRevisionMismatch(() => initializeOnce(db, context, sessionID, location, agent)).pipe(
-    Effect.withSpan("SessionContextEpoch.initialize"),
-  )
+  return initializeOnce(db, context, sessionID).pipe(Effect.withSpan("SessionContextEpoch.initialize"))
 }
 
 export function prepare(
@@ -56,12 +33,8 @@ export function prepare(
   events: EventV2.Interface,
   context: Effect.Effect<SystemContext.SystemContext>,
   sessionID: SessionSchema.ID,
-  location: Location.Ref,
-  agent: AgentV2.ID,
-): Effect.Effect<Prepared, SystemContext.InitializationBlocked | ContextSnapshotDecodeError | AgentReplacementBlocked> {
-  return retryRevisionMismatch(() => prepareOnce(db, events, context, sessionID, location, agent)).pipe(
-    Effect.withSpan("SessionContextEpoch.prepare"),
-  )
+): Effect.Effect<Prepared, SystemContext.InitializationBlocked | ContextSnapshotDecodeError> {
+  return prepareOnce(db, events, context, sessionID).pipe(Effect.withSpan("SessionContextEpoch.prepare"))
 }
 
 const prepareOnce = Effect.fnUntraced(function* (
@@ -69,57 +42,50 @@ const prepareOnce = Effect.fnUntraced(function* (
   events: EventV2.Interface,
   context: Effect.Effect<SystemContext.SystemContext>,
   sessionID: SessionSchema.ID,
-  location: Location.Ref,
-  agent: AgentV2.ID,
 ) {
-  const [value, stored] = yield* Effect.all([context, find(db, sessionID)], { concurrency: "unbounded" })
+  const [value, stored, compaction] = yield* Effect.all(
+    [context, find(db, sessionID), SessionHistory.latestCompaction(db, sessionID)],
+    { concurrency: "unbounded" },
+  )
   if (!stored) {
     const generation = yield* SystemContext.initialize(value)
-    const baselineSeq = yield* insert(db, sessionID, location, agent, generation)
-    return { baseline: generation.baseline, baselineSeq, revision: 0 }
+    const baselineSeq = yield* insert(db, sessionID, generation)
+    return { baseline: generation.baseline, baselineSeq }
   }
 
   const snapshot = yield* Schema.decodeUnknownEffect(SystemContext.Snapshot)(stored.snapshot).pipe(
     Effect.mapError((error) => new ContextSnapshotDecodeError({ sessionID, details: String(error) })),
   )
-  const replacingAgent = stored.agent !== agent
-  const result =
-    stored.replacement_seq === null && !replacingAgent
-      ? yield* SystemContext.reconcile(value, snapshot)
-      : yield* SystemContext.replace(value, snapshot)
-  if (result._tag === "ReplacementBlocked" && replacingAgent) {
-    yield* fence(db, sessionID, agent, stored.revision)
-    return yield* new AgentReplacementBlocked({ sessionID, previous: stored.agent, current: agent })
-  }
+  const replacementSeq = compaction !== undefined && compaction.seq > stored.baseline_seq ? compaction.seq : undefined
+  const result = replacementSeq
+    ? yield* SystemContext.replace(value, snapshot)
+    : yield* SystemContext.reconcile(value, snapshot)
   if (result._tag === "Unchanged" || result._tag === "ReplacementBlocked") {
-    yield* fence(db, sessionID, agent, stored.revision)
-    return { baseline: stored.baseline, baselineSeq: stored.baseline_seq, revision: stored.revision }
+    return { baseline: stored.baseline, baselineSeq: stored.baseline_seq }
   }
   if (result._tag === "ReplacementReady") {
-    const replacementSeq = stored.replacement_seq ?? (yield* SessionInput.latestSeq(db, sessionID))
-    yield* replace(db, sessionID, agent, stored.revision, replacementSeq, result.generation)
-    return { baseline: result.generation.baseline, baselineSeq: replacementSeq, revision: stored.revision + 1 }
+    const baselineSeq = replacementSeq ?? (yield* SessionInput.latestSeq(db, sessionID))
+    yield* replace(db, sessionID, baselineSeq, result.generation)
+    return { baseline: result.generation.baseline, baselineSeq }
   }
 
   yield* events.publish(
     SessionEvent.ContextUpdated,
     { sessionID, messageID: SessionMessageID.ID.create(), timestamp: yield* DateTime.now, text: result.text },
-    { commit: () => advance(db, sessionID, stored.revision, result.snapshot).pipe(Effect.orDie) },
+    { commit: () => advance(db, sessionID, result.snapshot).pipe(Effect.orDie) },
   )
-  return { baseline: stored.baseline, baselineSeq: stored.baseline_seq, revision: stored.revision + 1 }
+  return { baseline: stored.baseline, baselineSeq: stored.baseline_seq }
 })
 
 const initializeOnce = Effect.fnUntraced(function* (
   db: DatabaseService,
   context: Effect.Effect<SystemContext.SystemContext>,
   sessionID: SessionSchema.ID,
-  location: Location.Ref,
-  agent: AgentV2.ID,
 ) {
   if (yield* exists(db, sessionID)) return
   const generation = yield* context.pipe(Effect.flatMap(SystemContext.initialize))
-  const baselineSeq = yield* insert(db, sessionID, location, agent, generation)
-  return { baseline: generation.baseline, baselineSeq, revision: 0 }
+  const baselineSeq = yield* insert(db, sessionID, generation)
+  return { baseline: generation.baseline, baselineSeq }
 })
 
 const exists = Effect.fn("SessionContextEpoch.exists")(function* (db: DatabaseService, sessionID: SessionSchema.ID) {
@@ -142,39 +108,6 @@ const find = Effect.fn("SessionContextEpoch.find")(function* (db: DatabaseServic
     .pipe(Effect.orDie)
 })
 
-const requireAgentSelection = Effect.fnUntraced(function* (
-  db: DatabaseService,
-  sessionID: SessionSchema.ID,
-  agent: AgentV2.ID,
-) {
-  const selected = yield* db
-    .select({ agent: SessionTable.agent })
-    .from(SessionTable)
-    .where(eq(SessionTable.id, sessionID))
-    .get()
-    .pipe(Effect.orDie)
-  if (!selected || (selected.agent !== null && selected.agent !== agent)) return yield* Effect.die(new AgentMismatch())
-})
-
-export const requestReplacement = Effect.fn("SessionContextEpoch.requestReplacement")(function* (
-  db: DatabaseService,
-  sessionID: SessionSchema.ID,
-  seq: number,
-) {
-  return yield* db
-    .update(SessionContextEpochTable)
-    .set({ replacement_seq: seq, revision: sql`${SessionContextEpochTable.revision} + 1` })
-    .where(
-      and(
-        eq(SessionContextEpochTable.session_id, sessionID),
-        lt(SessionContextEpochTable.baseline_seq, seq),
-        or(isNull(SessionContextEpochTable.replacement_seq), lt(SessionContextEpochTable.replacement_seq, seq)),
-      ),
-    )
-    .run()
-    .pipe(Effect.orDie)
-})
-
 export const reset = Effect.fn("SessionContextEpoch.reset")(function* (
   db: DatabaseService,
   sessionID: SessionSchema.ID,
@@ -189,155 +122,53 @@ export const reset = Effect.fn("SessionContextEpoch.reset")(function* (
 const insert = Effect.fnUntraced(function* (
   db: DatabaseService,
   sessionID: SessionSchema.ID,
-  location: Location.Ref,
-  agent: AgentV2.ID,
   generation: SystemContext.Generation,
 ) {
-  return yield* db
-    .transaction(
-      () =>
-        Effect.gen(function* () {
-          const placed = yield* db
-            .select({ agent: SessionTable.agent })
-            .from(SessionTable)
-            .where(
-              and(
-                eq(SessionTable.id, sessionID),
-                eq(SessionTable.directory, location.directory),
-                location.workspaceID === undefined
-                  ? isNull(SessionTable.workspace_id)
-                  : eq(SessionTable.workspace_id, location.workspaceID),
-              ),
-            )
-            .get()
-            .pipe(Effect.orDie)
-          if (!placed) return yield* Effect.die(new LocationMismatch())
-          if (placed.agent !== null && placed.agent !== agent) return yield* Effect.die(new AgentMismatch())
-          const baselineSeq = yield* SessionInput.latestSeq(db, sessionID)
-          yield* db
-            .insert(SessionContextEpochTable)
-            .values({
-              session_id: sessionID,
-              baseline: generation.baseline,
-              agent,
-              snapshot: generation.snapshot,
-              baseline_seq: baselineSeq,
-              revision: 0,
-            })
-            .onConflictDoNothing()
-            .returning({ sessionID: SessionContextEpochTable.session_id })
-            .get()
-            .pipe(
-              Effect.orDie,
-              Effect.flatMap((inserted) => (inserted ? Effect.void : Effect.die(new RevisionMismatch()))),
-            )
-          return baselineSeq
-        }),
-      { behavior: "immediate" },
-    )
+  const baselineSeq = yield* SessionInput.latestSeq(db, sessionID)
+  yield* db
+    .insert(SessionContextEpochTable)
+    .values({
+      session_id: sessionID,
+      baseline: generation.baseline,
+      snapshot: generation.snapshot,
+      baseline_seq: baselineSeq,
+    })
+    .run()
     .pipe(Effect.orDie)
+  return baselineSeq
 })
 
 const replace = Effect.fnUntraced(function* (
   db: DatabaseService,
   sessionID: SessionSchema.ID,
-  agent: AgentV2.ID,
-  expectedRevision: number,
   baselineSeq: number,
   generation: SystemContext.Generation,
 ) {
-  yield* db
-    .transaction(
-      () =>
-        Effect.gen(function* () {
-          yield* requireAgentSelection(db, sessionID, agent)
-          const updated = yield* db
-            .update(SessionContextEpochTable)
-            .set({
-              baseline: generation.baseline,
-              agent,
-              snapshot: generation.snapshot,
-              baseline_seq: baselineSeq,
-              replacement_seq: null,
-              revision: expectedRevision + 1,
-            })
-            .where(
-              and(
-                eq(SessionContextEpochTable.session_id, sessionID),
-                eq(SessionContextEpochTable.revision, expectedRevision),
-              ),
-            )
-            .returning({ revision: SessionContextEpochTable.revision })
-            .get()
-            .pipe(Effect.orDie)
-          if (!updated) return yield* Effect.die(new RevisionMismatch())
-        }),
-      { behavior: "immediate" },
-    )
-    .pipe(Effect.orDie)
-})
-
-const fence = Effect.fnUntraced(function* (
-  db: DatabaseService,
-  sessionID: SessionSchema.ID,
-  agent: AgentV2.ID,
-  expectedRevision: number,
-) {
-  const current = yield* db
-    .select({ selected: SessionTable.agent, revision: SessionContextEpochTable.revision })
-    .from(SessionContextEpochTable)
-    .innerJoin(SessionTable, eq(SessionTable.id, SessionContextEpochTable.session_id))
-    .where(eq(SessionContextEpochTable.session_id, sessionID))
-    .get()
-    .pipe(Effect.orDie)
-  if (!current || (current.selected !== null && current.selected !== agent))
-    return yield* Effect.die(new AgentMismatch())
-  if (current.revision !== expectedRevision) return yield* Effect.die(new RevisionMismatch())
-})
-
-export const current = Effect.fn("SessionContextEpoch.current")(function* (
-  db: DatabaseService,
-  sessionID: SessionSchema.ID,
-  agent: AgentV2.ID,
-  revision: number,
-) {
-  const value = yield* db
-    .select({
-      agent: SessionContextEpochTable.agent,
-      selected: SessionTable.agent,
-      revision: SessionContextEpochTable.revision,
+  const updated = yield* db
+    .update(SessionContextEpochTable)
+    .set({
+      baseline: generation.baseline,
+      snapshot: generation.snapshot,
+      baseline_seq: baselineSeq,
     })
-    .from(SessionContextEpochTable)
-    .innerJoin(SessionTable, eq(SessionTable.id, SessionContextEpochTable.session_id))
     .where(eq(SessionContextEpochTable.session_id, sessionID))
+    .returning({ sessionID: SessionContextEpochTable.session_id })
     .get()
     .pipe(Effect.orDie)
-  return (
-    value !== undefined &&
-    value.agent === agent &&
-    (value.selected === null || value.selected === agent) &&
-    value.revision === revision
-  )
+  if (!updated) return yield* Effect.die("Context Epoch not found")
 })
 
 const advance = Effect.fnUntraced(function* (
   db: DatabaseService,
   sessionID: SessionSchema.ID,
-  expectedRevision: number,
   snapshot: SystemContext.Snapshot,
 ) {
   const updated = yield* db
     .update(SessionContextEpochTable)
-    .set({ snapshot, revision: expectedRevision + 1 })
-    .where(
-      and(
-        eq(SessionContextEpochTable.session_id, sessionID),
-        eq(SessionContextEpochTable.revision, expectedRevision),
-        isNull(SessionContextEpochTable.replacement_seq),
-      ),
-    )
-    .returning({ revision: SessionContextEpochTable.revision })
+    .set({ snapshot })
+    .where(eq(SessionContextEpochTable.session_id, sessionID))
+    .returning({ sessionID: SessionContextEpochTable.session_id })
     .get()
     .pipe(Effect.orDie)
-  if (!updated) return yield* Effect.die(new RevisionMismatch())
+  if (!updated) return yield* Effect.die("Context Epoch not found")
 })

packages/core/src/session/event.ts

@@ -27,13 +27,13 @@ const Base = {
 }
 
 const options = {
-  sync: {
+  durable: {
     aggregate: "sessionID",
     version: 1,
   },
 } as const
 const stepSettlementOptions = {
-  sync: {
+  durable: {
     aggregate: "sessionID",
     version: 2,
   },
@@ -118,13 +118,6 @@ export namespace PromptLifecycle {
   export type Promoted = typeof Promoted.Type
 }
 
-export const InterruptRequested = EventV2.define({
-  type: "session.next.interrupt.requested",
-  ...options,
-  schema: Base,
-})
-export type InterruptRequested = typeof InterruptRequested.Type
-
 export const ContextUpdated = EventV2.define({
   type: "session.next.context.updated",
   ...options,
@@ -443,20 +436,9 @@ export namespace Compaction {
   })
   export type Delta = typeof Delta.Type
 
-  // Retain the unpublished v1 decoder so stored beta events remain replayable.
-  export const EndedV1 = EventV2.define({
-    type: "session.next.compaction.ended",
-    ...options,
-    schema: {
-      ...Base,
-      text: Schema.String,
-      include: Schema.String.pipe(Schema.optional),
-    },
-  })
-
   export const Ended = EventV2.define({
     type: "session.next.compaction.ended",
-    sync: { aggregate: "sessionID", version: 2 },
+    ...options,
     schema: {
       ...Base,
       messageID: SessionMessageID.ID,
@@ -475,7 +457,6 @@ const DurableDefinitions = [
   Prompted,
   PromptLifecycle.Admitted,
   PromptLifecycle.Promoted,
-  InterruptRequested,
   ContextUpdated,
   Synthetic,
   Shell.Started,

packages/core/src/session/execution.ts

@@ -5,12 +5,12 @@ import { SessionRunner } from "./runner/index"
 import { SessionSchema } from "./schema"
 
 export interface Interface {
-  /** Explicitly drain one Session, making at least one provider attempt. */
+  /** Starts execution while idle or joins the active execution. */
   readonly resume: (sessionID: SessionSchema.ID) => Effect.Effect<void, SessionRunner.RunError>
-  /** Schedule a drain after durable work is recorded. Repeated wakeups may coalesce. */
-  readonly wake: (sessionID: SessionSchema.ID, seq?: number) => Effect.Effect<void, SessionRunner.RunError>
+  /** Registers newly recorded work. Repeated wakeups may coalesce. */
+  readonly wake: (sessionID: SessionSchema.ID) => Effect.Effect<void>
   /** Interrupt active work owned by this process. Idle interruption is a no-op. */
-  readonly interrupt: (sessionID: SessionSchema.ID, seq?: number) => Effect.Effect<void>
+  readonly interrupt: (sessionID: SessionSchema.ID) => Effect.Effect<void>
 }
 
 /** Routes execution from a Session ID to the runner owned by that Session's Location. */

packages/core/src/session/execution/local.ts

@@ -1,11 +1,10 @@
-import { Effect, Layer } from "effect"
+import { Cause, Effect, Layer } from "effect"
 import { LocationServiceMap } from "../../location-layer"
 import { SessionRunCoordinator } from "../run-coordinator"
 import { SessionRunner } from "../runner"
 import { SessionSchema } from "../schema"
 import { SessionStore } from "../store"
 import { SessionExecution } from "../execution"
-import { logFailure } from "../logging"
 
 /** Current-process routing for implicit-local Locations. Future remote placement belongs here. */
 export const layer = Layer.effect(
@@ -13,15 +12,19 @@ export const layer = Layer.effect(
   Effect.gen(function* () {
     const store = yield* SessionStore.Service
     const locations = yield* LocationServiceMap
-    const coordinator = yield* SessionRunCoordinator.make<SessionSchema.ID, void, SessionRunner.RunError>({
-      drain: Effect.fnUntraced(function* (sessionID: SessionSchema.ID, mode) {
+    const coordinator = yield* SessionRunCoordinator.make<SessionSchema.ID, SessionRunner.RunError>({
+      drain: Effect.fnUntraced(function* (sessionID: SessionSchema.ID, force) {
         const session = yield* store.get(sessionID)
         if (!session) return yield* Effect.die(`Session not found: ${sessionID}`)
-        return yield* SessionRunner.Service.use((runner) => runner.run({ sessionID, force: mode === "run" })).pipe(
+        return yield* SessionRunner.Service.use((runner) => runner.run({ sessionID, force })).pipe(
           Effect.provide(locations.get(session.location)),
+          Effect.tapCause((cause) =>
+            Cause.hasInterruptsOnly(cause)
+              ? Effect.void
+              : Effect.logError("Failed to drain Session", cause).pipe(Effect.annotateLogs({ sessionID })),
+          ),
         )
       }),
-      onFailure: (sessionID, cause) => logFailure("Failed to drain Session", sessionID, cause),
     })
 
     return SessionExecution.Service.of({

packages/core/src/session/history.ts

@@ -10,9 +10,9 @@ type DatabaseService = Database.Interface["db"]
 
 const decode = Schema.decodeUnknownEffect(SessionMessage.Message)
 
-const latestCompaction = Effect.fnUntraced(function* (db: DatabaseService, sessionID: SessionSchema.ID) {
+export const latestCompaction = Effect.fnUntraced(function* (db: DatabaseService, sessionID: SessionSchema.ID) {
   return yield* db
-    .select()
+    .select({ seq: SessionMessageTable.seq })
     .from(SessionMessageTable)
     .where(and(eq(SessionMessageTable.session_id, sessionID), eq(SessionMessageTable.type, "compaction")))
     .orderBy(desc(SessionMessageTable.seq))

packages/core/src/session/input.ts

@@ -74,11 +74,11 @@ export const admit = Effect.fn("SessionInput.admit")(function* (
     })
     .pipe(
       Effect.flatMap((event) =>
-        event.seq === undefined
+        event.durable === undefined
           ? Effect.die("Prompt admission event is missing aggregate sequence")
           : Effect.succeed(
               new Admitted({
-                admittedSeq: event.seq,
+                admittedSeq: event.durable.seq,
                 id: input.id,
                 sessionID: input.sessionID,
                 prompt: input.prompt,
@@ -117,13 +117,6 @@ export const projectAdmitted = Effect.fn("SessionInput.projectAdmitted")(functio
     readonly timeCreated: DateTime.Utc
   },
 ) {
-  const message = yield* db
-    .select({ id: SessionMessageTable.id })
-    .from(SessionMessageTable)
-    .where(eq(SessionMessageTable.id, input.id))
-    .get()
-    .pipe(Effect.orDie)
-  if (message) return yield* Effect.die(new LifecycleConflict({ id: input.id }))
   const stored = yield* db
     .insert(SessionInputTable)
     .values({
@@ -208,37 +201,6 @@ const matchesPrompt = (input: Admitted, expected: { readonly sessionID: SessionS
   input.sessionID === expected.sessionID &&
   JSON.stringify(encodePrompt(input.prompt)) === JSON.stringify(encodePrompt(expected.prompt))
 
-export const guardReservedID = Effect.fn("SessionInput.guardReservedID")(function* (
-  db: DatabaseService,
-  event: EventV2.Payload,
-) {
-  if (
-    Schema.is(SessionEvent.PromptLifecycle.Admitted)(event) ||
-    Schema.is(SessionEvent.PromptLifecycle.Promoted)(event)
-  )
-    return
-  const id = reservedID(event)
-  if (id === undefined) return
-  const admitted = yield* db
-    .select({ id: SessionInputTable.id })
-    .from(SessionInputTable)
-    .where(eq(SessionInputTable.id, id))
-    .get()
-    .pipe(Effect.orDie)
-  if (admitted === undefined) return
-  return yield* Effect.die(new LifecycleConflict({ id }))
-})
-
-const reservedID = (event: EventV2.Payload) => {
-  if (Schema.is(SessionEvent.Step.Started)(event)) return event.data.assistantMessageID
-  if (Schema.is(SessionEvent.AgentSwitched)(event)) return event.data.messageID
-  if (Schema.is(SessionEvent.ModelSwitched)(event)) return event.data.messageID
-  if (Schema.is(SessionEvent.Prompted)(event)) return event.data.messageID
-  if (Schema.is(SessionEvent.Synthetic)(event)) return event.data.messageID
-  if (Schema.is(SessionEvent.Shell.Started)(event)) return event.data.messageID
-  if (Schema.is(SessionEvent.Compaction.Started)(event)) return event.data.messageID
-}
-
 export const projectLegacyPrompted = Effect.fn("SessionInput.projectLegacyPrompted")(function* (
   db: DatabaseService,
   input: {

packages/core/src/session/logging.ts

@@ -1,8 +0,0 @@
-import { Cause, Effect } from "effect"
-import { SessionSchema } from "./schema"
-
-export const logFailure = (
-  message: "Failed to drain Session" | "Failed to wake Session",
-  sessionID: SessionSchema.ID,
-  cause: Cause.Cause<unknown>,
-) => Effect.logError(message, cause).pipe(Effect.annotateLogs({ sessionID }))

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

@@ -138,7 +138,6 @@ export function update(adapter: Adapter, event: SessionEvent.Event) {
       },
       "session.next.prompt.admitted": () => Effect.void,
       "session.next.prompt.promoted": () => Effect.void,
-      "session.next.interrupt.requested": () => Effect.void,
       "session.next.context.updated": (event) =>
         adapter.appendMessage(
           new SessionMessage.System({

packages/core/src/session/projector.ts

@@ -115,7 +115,7 @@ function run(db: DatabaseService, event: SessionEvent.Event) {
     const decodeRow = (row: typeof SessionMessageTable.$inferSelect) =>
       decodeMessage({ ...row.data, id: row.id, type: row.type })
     const updateMessage = (message: SessionMessage.Message) => {
-      if (event.seq === undefined) return Effect.die("Synchronized Session event is missing aggregate sequence")
+      if (event.durable === undefined) return Effect.die("Durable Session event is missing aggregate sequence")
       const encoded = encodeMessage(message)
       const { id, type, ...data } = encoded
       return db
@@ -192,7 +192,7 @@ function run(db: DatabaseService, event: SessionEvent.Event) {
 }
 
 function insertMessage(db: DatabaseService, event: SessionEvent.Event, message: SessionMessage.Message) {
-  if (event.seq === undefined) return Effect.die("Synchronized Session event is missing aggregate sequence")
+  if (event.durable === undefined) return Effect.die("Durable Session event is missing aggregate sequence")
   const encoded = encodeMessage(message)
   const { id, type, ...data } = encoded
   return db
@@ -201,7 +201,7 @@ function insertMessage(db: DatabaseService, event: SessionEvent.Event, message:
       id: SessionMessage.ID.make(id),
       session_id: event.data.sessionID,
       type,
-      seq: event.seq,
+      seq: event.durable.seq,
       time_created: DateTime.toEpochMillis(message.time.created),
       data,
     })
@@ -213,7 +213,6 @@ export const layer = Layer.effectDiscard(
   Effect.gen(function* () {
     const events = yield* EventV2.Service
     const { db } = yield* Database.Service
-    yield* events.beforeCommit((event) => SessionInput.guardReservedID(db, event))
     yield* events.project(SessionV1.Event.Created, (event) =>
       Effect.gen(function* () {
         const stored = yield* db
@@ -330,19 +329,14 @@ export const layer = Layer.effectDiscard(
         if (next) yield* applyUsage(db, sessionID, next)
       }),
     )
-    yield* events.project(SessionEvent.AgentSwitched, (event) => {
-      if (event.seq === undefined) return Effect.die("Synchronized Session event is missing aggregate sequence")
-      return db
+    yield* events.project(SessionEvent.AgentSwitched, (event) =>
+      db
         .update(SessionTable)
         .set({ agent: event.data.agent, time_updated: DateTime.toEpochMillis(event.data.timestamp) })
         .where(eq(SessionTable.id, event.data.sessionID))
         .run()
-        .pipe(
-          Effect.orDie,
-          Effect.andThen(run(db, event)),
-          Effect.andThen(SessionContextEpoch.requestReplacement(db, event.data.sessionID, event.seq)),
-        )
-    })
+        .pipe(Effect.orDie, Effect.andThen(run(db, event))),
+    )
     yield* events.project(SessionEvent.ModelSwitched, (event) =>
       Effect.gen(function* () {
         yield* db
@@ -352,9 +346,6 @@ export const layer = Layer.effectDiscard(
           .run()
           .pipe(Effect.orDie)
         yield* run(db, event)
-        if (event.seq === undefined)
-          return yield* Effect.die("Synchronized Session event is missing aggregate sequence")
-        yield* SessionContextEpoch.requestReplacement(db, event.data.sessionID, event.seq)
       }),
     )
     yield* events.project(SessionEvent.Prompted, (event) =>
@@ -368,24 +359,22 @@ export const layer = Layer.effectDiscard(
           .pipe(Effect.orDie)
         if (existing) return yield* Effect.die(new PromptAlreadyProjected())
         yield* run(db, event)
-        if (event.seq === undefined)
-          return yield* Effect.die("Synchronized Session event is missing aggregate sequence")
+        if (event.durable === undefined) return yield* Effect.die("Durable Session event is missing aggregate sequence")
         yield* SessionInput.projectLegacyPrompted(db, {
           id: messageID,
           sessionID: event.data.sessionID,
           prompt: event.data.prompt,
           delivery: event.data.delivery,
           timeCreated: event.data.timestamp,
-          promotedSeq: event.seq,
+          promotedSeq: event.durable.seq,
         })
       }),
     )
     yield* events.project(SessionEvent.PromptLifecycle.Admitted, (event) =>
       Effect.gen(function* () {
-        if (event.seq === undefined)
-          return yield* Effect.die("Synchronized Session event is missing aggregate sequence")
+        if (event.durable === undefined) return yield* Effect.die("Durable Session event is missing aggregate sequence")
         yield* SessionInput.projectAdmitted(db, {
-          admittedSeq: event.seq,
+          admittedSeq: event.durable.seq,
           id: event.data.messageID,
           sessionID: event.data.sessionID,
           prompt: event.data.prompt,
@@ -396,8 +385,7 @@ export const layer = Layer.effectDiscard(
     )
     yield* events.project(SessionEvent.PromptLifecycle.Promoted, (event) =>
       Effect.gen(function* () {
-        if (event.seq === undefined)
-          return yield* Effect.die("Synchronized Session event is missing aggregate sequence")
+        if (event.durable === undefined) return yield* Effect.die("Durable Session event is missing aggregate sequence")
         yield* insertMessage(
           db,
           event,
@@ -406,18 +394,12 @@ export const layer = Layer.effectDiscard(
             sessionID: event.data.sessionID,
             prompt: event.data.prompt,
             timeCreated: event.data.timeCreated,
-            promotedSeq: event.seq,
+            promotedSeq: event.durable.seq,
           }),
         )
       }),
     )
-    yield* events.project(SessionEvent.InterruptRequested, () => Effect.void)
-    yield* events.project(SessionEvent.ContextUpdated, (event) => {
-      if (!event.replay || event.seq === undefined) return run(db, event)
-      return run(db, event).pipe(
-        Effect.andThen(SessionContextEpoch.requestReplacement(db, event.data.sessionID, event.seq)),
-      )
-    })
+    yield* events.project(SessionEvent.ContextUpdated, (event) => run(db, event))
     yield* events.project(SessionEvent.Synthetic, (event) => run(db, event))
     yield* events.project(SessionEvent.Shell.Started, (event) => run(db, event))
     yield* events.project(SessionEvent.Shell.Ended, (event) => run(db, event))
@@ -435,15 +417,7 @@ export const layer = Layer.effectDiscard(
     yield* events.project(SessionEvent.Reasoning.Started, (event) => run(db, event))
     yield* events.project(SessionEvent.Reasoning.Ended, (event) => run(db, event))
     // yield* events.project(SessionEvent.Retried, (event) => run(db, event))
-    yield* events.project(SessionEvent.Compaction.Ended, (event) => {
-      if (event.version === 1) return Effect.void
-      const seq = event.seq
-      if (seq === undefined) return Effect.die("Synchronized Session event is missing aggregate sequence")
-      return Effect.gen(function* () {
-        yield* run(db, event)
-        yield* SessionContextEpoch.requestReplacement(db, event.data.sessionID, seq)
-      })
-    })
+    yield* events.project(SessionEvent.Compaction.Ended, (event) => run(db, event))
   }),
 )
 

packages/core/src/session/run-coordinator.ts

@@ -1,106 +1,43 @@
 export * as SessionRunCoordinator from "./run-coordinator"
 
-import { Cause, Context, Deferred, Effect, Exit, Fiber, FiberSet, Layer, Scope } from "effect"
-import { SessionRunner } from "./runner"
-import { logFailure } from "./logging"
-import { SessionSchema } from "./schema"
+import { Deferred, Effect, Exit, Fiber, FiberSet, Scope } from "effect"
 
-export type Mode = "run" | "wake"
-
-/** Why one drain generation should run. Explicit runs dominate advisory wakes when demands coalesce. */
-type Demand = { readonly _tag: "run" } | { readonly _tag: "wake"; readonly seq?: number }
-
-/**
- * Runs at most one drain chain per key while allowing different keys to drain concurrently.
- *
- * For each key:
- *
- *   idle --run/wake--> draining --run/wake--> draining + one coalesced rerun --> idle
- *
- * `run` is an explicit drain request. It starts a chain or joins the current chain and
- * upgrades a pending follow-up so the caller receives explicit-run semantics.
- *
- * `wake` reports that durable work may now be available. It starts a chain while idle or
- * requests one coalesced follow-up while draining. Repeated wakes collapse together.
- *
- * `interrupt` stops the current ownership chain. Advisory wakes from before the interrupt
- * boundary are suppressed; advisory wakes after the boundary run after cleanup.
- */
-export interface Coordinator<Key, A, E> {
-  /** Starts or joins one explicit drain generation. */
-  readonly run: (key: Key) => Effect.Effect<A, E>
-  /** Coalesces one wake-up after durable work is recorded. */
-  readonly wake: (key: Key, seq?: number) => Effect.Effect<void>
-  /** Waits until the current ownership chain settles. */
-  readonly awaitIdle: (key: Key) => Effect.Effect<void, E>
-  /** Interrupts the active ownership chain without automatically draining pending wakes. */
-  readonly interrupt: (key: Key, seq?: number) => Effect.Effect<void>
+/** Serializes execution for each key while allowing different keys to run concurrently. */
+export interface Coordinator<Key, E> {
+  /** Starts execution while idle or joins the active execution. */
+  readonly run: (key: Key) => Effect.Effect<void, E>
+  /** Registers one coalesced follow-up after newly recorded work. */
+  readonly wake: (key: Key) => Effect.Effect<void>
+  /** Stops active execution and waits for its cleanup. */
+  readonly interrupt: (key: Key) => Effect.Effect<void>
 }
 
-/** One Session's process-local execution lane: one active demand and at most one coalesced follow-up. */
-type Entry<A, E> = {
-  readonly done: Deferred.Deferred<A, E>
-  readonly settled: Deferred.Deferred<Exit.Exit<A, E>>
-  current: Demand
-  pending?: Demand
-  explicitWaiter?: Deferred.Deferred<A, E>
-  interruptSeq?: number
+type Entry<E> = {
+  readonly done: Deferred.Deferred<void, E>
   owner?: Fiber.Fiber<void, never>
+  pendingWake: boolean
   stopping: boolean
 }
 
-/** Combines follow-up demand: runs dominate, while wakes retain the newest durable admission sequence. */
-const coalesce = (left: Demand | undefined, right: Demand): Demand => {
-  if (left?._tag === "run" || right._tag === "run") return { _tag: "run" }
-  return { _tag: "wake", seq: maxSeq(left?.seq, right.seq) }
-}
-
-const maxSeq = (left: number | undefined, right: number | undefined) => {
-  if (left === undefined) return right
-  if (right === undefined) return left
-  return Math.max(left, right)
-}
-
-/** Constructs a scoped coordinator. Every in-memory transition is synchronous. */
-export const make = <Key, A, E>(options: {
-  readonly drain: (key: Key, mode: Mode) => Effect.Effect<A, E>
-  readonly onFailure?: (key: Key, cause: Cause.Cause<E>) => Effect.Effect<void>
-}): Effect.Effect<Coordinator<Key, A, E>, never, Scope.Scope> =>
+export const make = <Key, E>(options: {
+  readonly drain: (key: Key, force: boolean) => Effect.Effect<void, E>
+}): Effect.Effect<Coordinator<Key, E>, never, Scope.Scope> =>
   Effect.gen(function* () {
-    const active = new Map<Key, Entry<A, E>>()
-    const interruptSeq = new Map<Key, number>()
-    const report = yield* FiberSet.makeRuntime<never, void, never>()
+    const active = new Map<Key, Entry<E>>()
     const fork = yield* FiberSet.makeRuntime<never, void, never>()
-    const shutdown = Deferred.makeUnsafe<void>()
-    let closed = false
-    yield* Effect.addFinalizer(() =>
-      Effect.sync(() => {
-        closed = true
-        Deferred.doneUnsafe(shutdown, Effect.void)
-        active.clear()
-        interruptSeq.clear()
-      }),
-    )
 
-    const makeEntry = (current: Demand, explicitWaiter?: Deferred.Deferred<A, E>): Entry<A, E> => ({
-      done: Deferred.makeUnsafe<A, E>(),
-      settled: Deferred.makeUnsafe<Exit.Exit<A, E>>(),
-      current,
-      explicitWaiter,
+    const makeEntry = (): Entry<E> => ({
+      done: Deferred.makeUnsafe<void, E>(),
+      pendingWake: false,
       stopping: false,
     })
 
-    const start = (key: Key, entry: Entry<A, E>, demand: Demand, successor = false) => {
+    const start = (key: Key, entry: Entry<E>, force: boolean, successor = false) => {
       const ready = Deferred.makeUnsafe<void>()
-      const drain = Effect.suspend(() => options.drain(key, demand._tag))
-      // Initial work retains immediate-start behavior but cannot run before ownership is published.
-      // Observer-started successors yield once so synchronous drains cannot recurse on the JS stack.
       const owner = fork(
-        (successor
-          ? Effect.yieldNow.pipe(Effect.andThen(drain))
-          : Deferred.await(ready).pipe(Effect.andThen(drain))
-        ).pipe(
-          Effect.onExit((exit) => Effect.sync(() => settle(key, entry, demand, exit))),
+        (successor ? Effect.yieldNow : Deferred.await(ready)).pipe(
+          Effect.andThen(Effect.suspend(() => options.drain(key, force))),
+          Effect.onExit((exit) => Effect.sync(() => settle(key, entry, exit))),
           Effect.exit,
           Effect.asVoid,
         ),
@@ -109,176 +46,57 @@ export const make = <Key, A, E>(options: {
       if (!successor) Deferred.doneUnsafe(ready, Effect.void)
     }
 
-    const settle = (key: Key, entry: Entry<A, E>, demand: Demand, exit: Exit.Exit<A, E>) => {
-      if (closed) {
-        Deferred.doneUnsafe(entry.done, exit)
-        Deferred.doneUnsafe(entry.settled, Effect.succeed(exit))
-        return
-      }
-      if (demand._tag === "run" && entry.explicitWaiter !== undefined) {
-        Deferred.doneUnsafe(entry.explicitWaiter, exit)
-        entry.explicitWaiter = undefined
-      }
-      if (entry.stopping && demand._tag === "wake" && entry.explicitWaiter !== undefined) {
-        Deferred.doneUnsafe(entry.explicitWaiter, exit)
-        entry.explicitWaiter = undefined
-      }
-      if (active.get(key) !== entry) {
-        Deferred.doneUnsafe(entry.done, exit)
-        Deferred.doneUnsafe(entry.settled, Effect.succeed(exit))
-        return
-      }
-      if (exit._tag === "Success" && !entry.stopping) {
-        if (entry.pending !== undefined) {
-          const pending = entry.pending
-          entry.pending = undefined
-          entry.current = pending
-          start(key, entry, pending, true)
-          return
-        }
-        active.delete(key)
-        Deferred.doneUnsafe(entry.done, exit)
-        Deferred.doneUnsafe(entry.settled, Effect.succeed(exit))
+    const settle = (key: Key, entry: Entry<E>, exit: Exit.Exit<void, E>) => {
+      if (Exit.isSuccess(exit) && !entry.stopping && entry.pendingWake) {
+        entry.pendingWake = false
+        start(key, entry, false, true)
         return
       }
 
-      const successor = entry.pending !== undefined ? makeEntry(entry.pending, entry.explicitWaiter) : undefined
+      const successor = entry.pendingWake ? makeEntry() : undefined
       if (successor === undefined) active.delete(key)
-      else active.set(key, successor)
-      if (successor !== undefined) start(key, successor, successor.current, true)
-      Deferred.doneUnsafe(entry.done, exit)
-      Deferred.doneUnsafe(entry.settled, Effect.succeed(exit))
-      if (
-        exit._tag === "Failure" &&
-        !(entry.stopping && Cause.hasInterruptsOnly(exit.cause)) &&
-        demand._tag === "wake" &&
-        options.onFailure !== undefined
-      ) {
-        report(Effect.suspend(() => options.onFailure!(key, exit.cause)))
+      else {
+        active.set(key, successor)
+        start(key, successor, false, true)
       }
+      Deferred.doneUnsafe(entry.done, exit)
     }
 
-    const wake = (key: Key, seq?: number) =>
-      Effect.sync(() => {
-        if (closed) return
-        if (!isAfterInterrupt(key, seq)) return
+    const run = (key: Key): Effect.Effect<void, E> =>
+      Effect.uninterruptibleMask((restore) => {
         const entry = active.get(key)
         if (entry !== undefined) {
-          if (!acceptsWake(entry, seq)) return
-          entry.pending = coalesce(entry.pending, { _tag: "wake", seq })
+          if (entry.stopping) return restore(Deferred.await(entry.done).pipe(Effect.andThen(run(key))))
+          return restore(Deferred.await(entry.done))
+        }
+
+        const next = makeEntry()
+        active.set(key, next)
+        start(key, next, true)
+        return restore(Deferred.await(next.done))
+      })
+
+    const wake = (key: Key) =>
+      Effect.sync(() => {
+        const entry = active.get(key)
+        if (entry !== undefined) {
+          entry.pendingWake = true
           return
         }
 
-        const next = makeEntry({ _tag: "wake", seq })
+        const next = makeEntry()
         active.set(key, next)
-        start(key, next, next.current)
+        start(key, next, false)
       })
 
-    const awaitIdle = (key: Key): Effect.Effect<void, E> =>
-      Effect.gen(function* () {
-        let firstFailure: Cause.Cause<E> | undefined
-        while (!closed) {
-          const entry = active.get(key)
-          if (entry === undefined) break
-          const exit = yield* Effect.raceFirst(
-            Deferred.await(entry.settled),
-            Deferred.await(shutdown).pipe(Effect.as(Exit.void)),
-          )
-          if (closed) break
-          if (exit._tag === "Failure" && firstFailure === undefined) firstFailure = exit.cause
-        }
-        if (firstFailure !== undefined) return yield* Effect.failCause(firstFailure)
-      })
-
-    const interrupt = (key: Key, seq?: number): Effect.Effect<void> =>
+    const interrupt = (key: Key): Effect.Effect<void> =>
       Effect.suspend(() => {
         const entry = active.get(key)
-        const latest = interruptSeq.get(key)
-        if (seq !== undefined && latest !== undefined && seq <= latest)
-          return entry?.stopping && entry.owner !== undefined ? Fiber.interrupt(entry.owner) : Effect.void
-        if (seq !== undefined) interruptSeq.set(key, seq)
         if (entry?.owner === undefined) return Effect.void
-        if (
-          seq !== undefined &&
-          entry.current._tag === "wake" &&
-          entry.current.seq !== undefined &&
-          entry.current.seq > seq
-        )
-          return Effect.void
-        if (entry.stopping) {
-          entry.interruptSeq = maxSeq(entry.interruptSeq, seq)
-          suppressPendingAtOrBefore(entry, seq)
-          return Fiber.interrupt(entry.owner)
-        }
         entry.stopping = true
-        entry.interruptSeq = seq
-        suppressPendingAtOrBefore(entry, seq)
+        entry.pendingWake = false
         return Fiber.interrupt(entry.owner)
       })
 
-    return { run, wake, awaitIdle, interrupt }
-
-    function run(key: Key): Effect.Effect<A, E> {
-      return Effect.uninterruptibleMask((restore) => {
-        if (closed) return Effect.interrupt
-        const entry = active.get(key)
-        if (entry !== undefined) {
-          if (entry.stopping) {
-            return restore(Deferred.await(entry.settled).pipe(Effect.andThen(run(key))))
-          }
-          if (entry.current._tag === "wake") {
-            entry.pending = coalesce(entry.pending, { _tag: "run" })
-            entry.explicitWaiter ??= Deferred.makeUnsafe<A, E>()
-            return restore(awaitRun(entry.explicitWaiter))
-          }
-          return restore(awaitRun(entry.done))
-        }
-
-        const next = makeEntry({ _tag: "run" })
-        active.set(key, next)
-        start(key, next, next.current)
-        return restore(awaitRun(next.done))
-      })
-    }
-
-    function awaitRun(done: Deferred.Deferred<A, E>): Effect.Effect<A, E> {
-      return Effect.raceFirst(Deferred.await(done), Deferred.await(shutdown).pipe(Effect.andThen(Effect.interrupt)))
-    }
-
-    function acceptsWake(entry: Entry<A, E>, seq: number | undefined) {
-      return !entry.stopping || (entry.interruptSeq !== undefined && seq !== undefined && seq > entry.interruptSeq)
-    }
-
-    function isAfterInterrupt(key: Key, seq: number | undefined) {
-      const latest = interruptSeq.get(key)
-      return latest === undefined || (seq !== undefined && seq > latest)
-    }
-
-    function suppressPendingAtOrBefore(entry: Entry<A, E>, seq: number | undefined) {
-      if (
-        entry.pending?._tag === "wake" &&
-        seq !== undefined &&
-        entry.pending.seq !== undefined &&
-        entry.pending.seq > seq
-      )
-        return
-      entry.pending = undefined
-    }
+    return { run, wake, interrupt }
   })
-
-export interface Interface extends Coordinator<SessionSchema.ID, void, SessionRunner.RunError> {}
-
-export class Service extends Context.Service<Service, Interface>()("@opencode/v2/SessionRunCoordinator") {}
-
-export const layer = Layer.effect(
-  Service,
-  SessionRunner.Service.pipe(
-    Effect.flatMap((runner) =>
-      make<SessionSchema.ID, void, SessionRunner.RunError>({
-        drain: (sessionID, mode) => runner.run({ sessionID, force: mode === "run" }),
-        onFailure: (sessionID, cause) => logFailure("Failed to drain Session", sessionID, cause),
-      }),
-    ),
-    Effect.map(Service.of),
-  ),
-)

packages/core/src/session/runner/index.ts

@@ -6,7 +6,6 @@ import { SessionSchema } from "../schema"
 import type { ContextSnapshotDecodeError, MessageDecodeError } from "../error"
 import { SessionRunnerModel } from "./model"
 import type { SystemContext } from "../../system-context/index"
-import type { SessionContextEpoch } from "../context-epoch"
 import type { ToolOutputStore } from "../../tool-output-store"
 
 export type RunError =
@@ -15,7 +14,6 @@ export type RunError =
   | MessageDecodeError
   | ContextSnapshotDecodeError
   | SystemContext.InitializationBlocked
-  | SessionContextEpoch.AgentReplacementBlocked
   | ToolOutputStore.Error
 
 /** Runs one local continuation from already-recorded Session history. */
@@ -23,7 +21,7 @@ export interface Interface {
   /** Drains eligible durable work. Explicit runs perform one provider attempt even when no work is eligible. */
   readonly run: (input: {
     readonly sessionID: SessionSchema.ID
-    readonly force?: boolean
+    readonly force: boolean
   }) => Effect.Effect<void, RunError>
 }
 

packages/core/src/session/runner/llm.ts

@@ -8,7 +8,7 @@ import {
   isContextOverflowFailure,
   type ProviderErrorEvent,
 } from "@opencode-ai/llm"
-import { Cause, DateTime, Effect, FiberSet, Layer, Option, Schema, Semaphore, Stream } from "effect"
+import { Cause, DateTime, Effect, FiberSet, Layer, Option, Semaphore, Stream } from "effect"
 import { AgentV2 } from "../../agent"
 import { Config } from "../../config"
 import { Database } from "../../database/database"
@@ -141,8 +141,8 @@ export const layer = Layer.effect(
       cause.reasons.some((reason) => Cause.isDieReason(reason) && reason.defect instanceof QuestionV2.RejectedError)
 
     type TurnTransition =
-      // Request preparation observed a concurrent Session change and must restart from durable state.
-      | { readonly _tag: "RebuildPreparedTurn"; readonly promotion?: SessionInput.Delivery }
+      // Automatic compaction completed; rebuild the request from compacted history.
+      | { readonly _tag: "ContinueAfterCompaction" }
       // Overflow compaction completed; rebuild once through the path without overflow recovery.
       | { readonly _tag: "ContinueAfterOverflowCompaction" }
 
@@ -152,20 +152,11 @@ export const layer = Layer.effect(
       }
     }
 
-    const rebuildPreparedTurn = (promotion?: SessionInput.Delivery) =>
-      new TurnTransitionError({ _tag: "RebuildPreparedTurn", promotion })
+    const continueAfterCompaction = new TurnTransitionError({ _tag: "ContinueAfterCompaction" })
     const continueAfterOverflowCompaction = new TurnTransitionError({
       _tag: "ContinueAfterOverflowCompaction",
     })
 
-    const retryAgentMismatch = (promotion: SessionInput.Delivery | undefined) =>
-      Effect.catchDefect((defect) =>
-        defect instanceof SessionContextEpoch.AgentMismatch
-          ? Effect.die(rebuildPreparedTurn(promotion))
-          : Effect.die(defect),
-      )
-
-    const sameModel = Schema.toEquivalence(Schema.UndefinedOr(ModelV2.Ref))
     const loadSystemContext = (agent: AgentV2.Selection) =>
       Effect.all([systemContext.load(), skillGuidance.load(agent), referenceGuidance.load()], {
         concurrency: "unbounded",
@@ -181,13 +172,7 @@ export const layer = Layer.effect(
       if (session.location.directory !== location.directory || session.location.workspaceID !== location.workspaceID)
         return yield* Effect.interrupt
       const agent = yield* agents.select(session.agent)
-      const initialized = yield* SessionContextEpoch.initialize(
-        db,
-        loadSystemContext(agent),
-        session.id,
-        session.location,
-        agent.id,
-      ).pipe(retryAgentMismatch(promotion))
+      const initialized = yield* SessionContextEpoch.initialize(db, loadSystemContext(agent), session.id)
       const toolFibers = yield* FiberSet.make<void, ToolOutputStore.Error>()
       let needsContinuation = false
       if (promotion) {
@@ -199,18 +184,7 @@ export const layer = Layer.effect(
         }
       }
       const system =
-        initialized ??
-        (yield* SessionContextEpoch.prepare(
-          db,
-          events,
-          loadSystemContext(agent),
-          session.id,
-          session.location,
-          agent.id,
-        ).pipe(retryAgentMismatch(undefined)))
-      const current = yield* getSession(sessionID)
-      if ((yield* agents.select(current.agent)).id !== agent.id || !sameModel(current.model, session.model))
-        return yield* Effect.die(rebuildPreparedTurn())
+        initialized ?? (yield* SessionContextEpoch.prepare(db, events, loadSystemContext(agent), session.id))
       const model = yield* models.resolve(session)
       const entries = yield* SessionHistory.entriesForRunner(db, session.id, system.baselineSeq)
       const context = entries.map((entry) => entry.message)
@@ -228,7 +202,7 @@ export const layer = Layer.effect(
         toolChoice: isLastStep ? "none" : undefined,
       })
       if (yield* compaction.compactIfNeeded({ sessionID: session.id, entries, model, request }))
-        return yield* Effect.die(rebuildPreparedTurn())
+        return yield* Effect.die(continueAfterCompaction)
       const publisher = createLLMEventPublisher(events, {
         sessionID: session.id,
         agent: agent.id,
@@ -242,8 +216,6 @@ export const layer = Layer.effect(
       const publish = (event: LLMEvent, outputPaths: ReadonlyArray<string> = []) =>
         withPublication(publisher.publish(event, outputPaths))
       let overflowFailure: ProviderErrorEvent | undefined
-      if (!(yield* SessionContextEpoch.current(db, session.id, agent.id, system.revision)))
-        return yield* Effect.die(rebuildPreparedTurn())
       const providerStream = llm.stream(request).pipe(
         Stream.runForEach((event) =>
           Effect.gen(function* () {
@@ -305,14 +277,7 @@ export const layer = Layer.effect(
           const llmFailure = failure instanceof LLMError ? failure : undefined
           if (llmFailure && !publisher.hasProviderError()) {
             yield* withPublication(publisher.failUnsettledTools("Provider did not return a tool result", true))
-            yield* withPublication(
-              events.publish(SessionEvent.Step.Failed, {
-                sessionID: session.id,
-                timestamp: yield* DateTime.now,
-                assistantMessageID: yield* publisher.startAssistant(),
-                error: { type: "unknown", message: llmFailure.reason.message },
-              }),
-            )
+            yield* withPublication(publisher.failAssistant(llmFailure.reason.message))
           }
           if (stream._tag === "Failure" && Cause.hasInterrupts(stream.cause)) yield* FiberSet.clear(toolFibers)
           const settled = yield* restore(awaitToolFibers(toolFibers)).pipe(Effect.exit)
@@ -327,6 +292,8 @@ export const layer = Layer.effect(
           ) {
             yield* FiberSet.clear(toolFibers)
             yield* withPublication(publisher.failUnsettledTools("Tool execution interrupted"))
+            if (publisher.hasActiveAssistant())
+              yield* withPublication(publisher.failAssistant("Provider turn interrupted"))
           }
           if (settled._tag === "Failure" && !Cause.hasInterrupts(settled.cause)) {
             const failure = Cause.squash(settled.cause)
@@ -357,7 +324,7 @@ export const layer = Layer.effect(
             if (defect.transition._tag === "ContinueAfterOverflowCompaction")
               return yield* Effect.die("Post-compaction provider attempt cannot recover another overflow")
             yield* Effect.yieldNow
-            return yield* runAfterOverflowCompaction(sessionID, defect.transition.promotion, step)
+            return yield* runAfterOverflowCompaction(sessionID, undefined, step)
           }),
         ),
       )
@@ -371,7 +338,7 @@ export const layer = Layer.effect(
             yield* Effect.yieldNow
             if (defect.transition._tag === "ContinueAfterOverflowCompaction")
               return yield* runAfterOverflowCompaction(sessionID, undefined, step)
-            return yield* runTurn(sessionID, defect.transition.promotion, step)
+            return yield* runTurn(sessionID, undefined, step)
           }),
         ),
       )
@@ -379,14 +346,14 @@ export const layer = Layer.effect(
 
     const run = Effect.fn("SessionRunner.run")(function* (input: {
       readonly sessionID: SessionSchema.ID
-      readonly force?: boolean
+      readonly force: boolean
     }) {
       const hasSteer = yield* SessionInput.hasPending(db, input.sessionID, "steer")
       const hasQueue = hasSteer ? false : yield* SessionInput.hasPending(db, input.sessionID, "queue")
-      if (input.force !== true && !hasSteer && !hasQueue) return
+      if (!input.force && !hasSteer && !hasQueue) return
       yield* failInterruptedTools(input.sessionID)
       let promotion: SessionInput.Delivery | undefined = hasSteer ? "steer" : hasQueue ? "queue" : undefined
-      let openActivity = input.force === true || hasSteer || hasQueue
+      let openActivity = input.force || hasSteer || hasQueue
       while (openActivity) {
         let needsContinuation = true
         for (let step = 1; needsContinuation; step++) {

packages/core/src/session/runner/model.ts

@@ -5,7 +5,7 @@ import * as AnthropicMessages from "@opencode-ai/llm/protocols/anthropic-message
 import * as OpenAICompatibleChat from "@opencode-ai/llm/protocols/openai-compatible-chat"
 import * as OpenAIResponses from "@opencode-ai/llm/protocols/openai-responses"
 import { Auth, type AnyRoute } from "@opencode-ai/llm/route"
-import { Context, Effect, Layer, Option, Schema } from "effect"
+import { Context, Effect, Layer, Schema } from "effect"
 import { produce } from "immer"
 import { Catalog } from "../../catalog"
 import { Credential } from "../../credential"
@@ -24,6 +24,23 @@ export class ModelNotSelectedError extends Schema.TaggedErrorClass<ModelNotSelec
   },
 ) {}
 
+export class ModelUnavailableError extends Schema.TaggedErrorClass<ModelUnavailableError>()(
+  "SessionRunnerModel.ModelUnavailableError",
+  {
+    providerID: ProviderV2.ID,
+    modelID: ModelV2.ID,
+  },
+) {}
+
+export class VariantUnavailableError extends Schema.TaggedErrorClass<VariantUnavailableError>()(
+  "SessionRunnerModel.VariantUnavailableError",
+  {
+    providerID: ProviderV2.ID,
+    modelID: ModelV2.ID,
+    variant: ModelV2.VariantID,
+  },
+) {}
+
 export class UnsupportedApiError extends Schema.TaggedErrorClass<UnsupportedApiError>()(
   "SessionRunnerModel.UnsupportedApiError",
   {
@@ -33,7 +50,7 @@ export class UnsupportedApiError extends Schema.TaggedErrorClass<UnsupportedApiE
   },
 ) {}
 
-export type Error = ModelNotSelectedError | UnsupportedApiError
+export type Error = ModelNotSelectedError | ModelUnavailableError | VariantUnavailableError | UnsupportedApiError
 
 export interface Interface {
   readonly resolve: (session: SessionSchema.Info) => Effect.Effect<Model, Error>
@@ -44,7 +61,7 @@ export class Service extends Context.Service<Service, Interface>()("@opencode/v2
 /** Test or embedding seam for supplying a model resolver directly. */
 export const layerWith = (resolve: Interface["resolve"]) => Layer.succeed(Service, Service.of({ resolve }))
 
-const apiKey = (model: ModelV2.Info, connection?: IntegrationConnection.Info, credential?: Credential.Stored) => {
+const apiKey = (model: ModelV2.Info, connection?: IntegrationConnection.Info, credential?: Credential.Info) => {
   if (credential?.value.type === "key") return Auth.value(credential.value.key)
   if (credential?.value.type === "oauth") return Auth.value(credential.value.access)
   const value = model.request.body.apiKey ?? model.api.settings?.apiKey
@@ -70,13 +87,27 @@ const withDefaults = (model: ModelV2.Info, route: AnyRoute) => {
   })
 }
 
-const withVariant = (model: ModelV2.Info, variantID: ModelV2.VariantID | undefined) => {
+const withVariant = (
+  model: ModelV2.Info,
+  variantID: ModelV2.VariantID | undefined,
+): Effect.Effect<ModelV2.Info, VariantUnavailableError> => {
   const id = variantID === "default" || variantID === undefined ? model.request.variant : variantID
   const variant = model.variants.find((item) => item.id === id)
-  if (!variant) return model
-  return produce(model, (draft) => {
-    ModelRequest.assign(draft.request, variant)
-  })
+  if (!variant && variantID !== undefined && variantID !== "default")
+    return Effect.fail(
+      new VariantUnavailableError({
+        providerID: model.providerID,
+        modelID: model.id,
+        variant: variantID,
+      }),
+    )
+  return Effect.succeed(
+    variant
+      ? produce(model, (draft) => {
+          ModelRequest.assign(draft.request, variant)
+        })
+      : model,
+  )
 }
 
 const apiName = (model: ModelV2.Info) =>
@@ -85,7 +116,7 @@ const apiName = (model: ModelV2.Info) =>
 export const fromCatalogModel = (
   model: ModelV2.Info,
   connection?: IntegrationConnection.Info,
-  credential?: Credential.Stored,
+  credential?: Credential.Info,
 ): Effect.Effect<Model, UnsupportedApiError> => {
   const resolved =
     credential?.value.metadata === undefined
@@ -124,8 +155,15 @@ export const fromCatalogModel = (
   )
 }
 
-export const resolve = (session: SessionSchema.Info, model: ModelV2.Info) =>
-  fromCatalogModel(withVariant(model, session.model?.variant))
+export const resolve = (
+  session: SessionSchema.Info,
+  model: ModelV2.Info,
+  connection?: IntegrationConnection.Info,
+  credential?: Credential.Info,
+) =>
+  withVariant(model, session.model?.variant).pipe(
+    Effect.flatMap((model) => fromCatalogModel(model, connection, credential)),
+  )
 
 export const supported = (model: ModelV2.Info) =>
   model.api.type === "aisdk" &&
@@ -147,14 +185,22 @@ export const locationLayer = Layer.effect(
         yield* boot.wait()
         const defaultModel = session.model ? undefined : yield* catalog.model.default()
         const selected = session.model
-          ? yield* catalog.model.get(session.model.providerID, session.model.id)
+          ? (yield* catalog.model.available()).find(
+              (model) => model.providerID === session.model?.providerID && model.id === session.model.id,
+            )
           : defaultModel && supported(defaultModel)
             ? defaultModel
             : (yield* catalog.model.available()).find(supported)
+        if (!selected && session.model)
+          return yield* new ModelUnavailableError({
+            providerID: session.model.providerID,
+            modelID: session.model.id,
+          })
         if (!selected) return yield* new ModelNotSelectedError({ sessionID: session.id })
         const connection = yield* integrations.connection.forIntegration(Integration.ID.make(selected.providerID))
-        return yield* fromCatalogModel(
-          withVariant(selected, session.model?.variant),
+        return yield* resolve(
+          session,
+          selected,
           connection,
           connection?.type === "credential" ? yield* credentials.get(connection.id) : undefined,
         )

packages/core/src/session/runner/publish-llm-event.ts

@@ -65,11 +65,14 @@ export const createLLMEventPublisher = (events: EventV2.Interface, input: Input)
   >()
   const timestamp = DateTime.now
   let assistantMessageID: SessionMessage.ID | undefined
+  let assistantActive = false
+  let assistantFailed = false
   let providerFailed = false
 
   const startAssistant = Effect.fnUntraced(function* () {
     if (assistantMessageID !== undefined) return assistantMessageID
     assistantMessageID = SessionMessage.ID.create()
+    assistantActive = true
     yield* events.publish(SessionEvent.Step.Started, {
       ...input,
       assistantMessageID,
@@ -190,6 +193,20 @@ export const createLLMEventPublisher = (events: EventV2.Interface, input: Input)
     yield* flushFragments()
   })
 
+  const failAssistant = Effect.fnUntraced(function* (message: string) {
+    if (assistantFailed) return
+    yield* flush()
+    const assistantMessageID = yield* startAssistant()
+    assistantActive = false
+    assistantFailed = true
+    yield* events.publish(SessionEvent.Step.Failed, {
+      sessionID: input.sessionID,
+      timestamp: yield* timestamp,
+      assistantMessageID,
+      error: { type: "unknown", message },
+    })
+  })
+
   const failUnsettledTools = Effect.fn("SessionRunner.failUnsettledTools")(function* (
     message: string,
     hostedOnly = false,
@@ -375,6 +392,7 @@ export const createLLMEventPublisher = (events: EventV2.Interface, input: Input)
       }
       case "step-finish":
         yield* flush()
+        assistantActive = false
         yield* events.publish(SessionEvent.Step.Ended, {
           sessionID: input.sessionID,
           timestamp: yield* timestamp,
@@ -388,13 +406,7 @@ export const createLLMEventPublisher = (events: EventV2.Interface, input: Input)
         return
       case "provider-error":
         providerFailed = true
-        yield* flush()
-        yield* events.publish(SessionEvent.Step.Failed, {
-          sessionID: input.sessionID,
-          timestamp: yield* timestamp,
-          assistantMessageID: yield* startAssistant(),
-          error: { type: "unknown", message: event.message },
-        })
+        yield* failAssistant(event.message)
         return
     }
   })
@@ -402,10 +414,11 @@ export const createLLMEventPublisher = (events: EventV2.Interface, input: Input)
   return {
     publish,
     flush,
+    failAssistant,
     failUnsettledTools,
+    hasActiveAssistant: () => assistantActive,
     hasAssistantStarted: () => assistantMessageID !== undefined,
     hasProviderError: () => providerFailed,
-    startAssistant,
     assistantMessageID: assistantMessageIDForTool,
   }
 }

packages/core/src/session/runner/to-llm-message.ts

@@ -82,12 +82,21 @@ const assistant = (message: SessionMessage.Assistant, model: Model) => {
     const result = toolResult(item, sameModel ? (item.provider?.resultMetadata ?? item.provider?.metadata) : undefined)
     return item.provider?.executed === true && result ? [call, result] : [call]
   })
+  const meaningful = content.filter((part) => {
+    if (part.type === "text") return part.text !== ""
+    if (part.type !== "reasoning") return true
+    return part.text !== "" || (part.providerMetadata !== undefined && Object.keys(part.providerMetadata).length > 0)
+  })
   const results = message.content
     .filter((item): item is SessionMessage.AssistantTool => item.type === "tool" && item.provider?.executed !== true)
     .map((item) => toolResult(item, sameModel ? (item.provider?.resultMetadata ?? item.provider?.metadata) : undefined))
     .filter((message) => message !== undefined)
     .map(Message.tool)
-  return [Message.make({ id: message.id, role: "assistant", content, metadata: message.metadata }), ...results]
+  if (meaningful.length === 0) return results
+  return [
+    Message.make({ id: message.id, role: "assistant", content: meaningful, metadata: message.metadata }),
+    ...results,
+  ]
 }
 
 function toLLMMessage(message: SessionMessage.Message, model: Model): Message[] {

packages/core/src/session/sql.ts

@@ -170,9 +170,6 @@ export const SessionContextEpochTable = sqliteTable("session_context_epoch", {
     .primaryKey()
     .references(() => SessionTable.id, { onDelete: "cascade" }),
   baseline: text().notNull(),
-  agent: text().$type<AgentV2.ID>().notNull().default(AgentV2.defaultID),
   snapshot: text({ mode: "json" }).notNull().$type<SystemContext.Snapshot>(),
   baseline_seq: integer().notNull(),
-  replacement_seq: integer(),
-  revision: integer().notNull().default(0),
 })

packages/core/src/tool/http-body.ts

@@ -0,0 +1,30 @@
+import { Effect, Stream } from "effect"
+import { HttpClientResponse } from "effect/unstable/http"
+
+export const collectBoundedResponseBody = (
+  response: HttpClientResponse.HttpClientResponse,
+  maximumBytes: number,
+  tooLarge: () => Error,
+) =>
+  Effect.gen(function* () {
+    const contentLength = response.headers["content-length"]
+    const parsedSize = contentLength ? Number.parseInt(contentLength, 10) : undefined
+    const declaredSize =
+      parsedSize !== undefined && Number.isSafeInteger(parsedSize) && parsedSize >= 0 ? parsedSize : undefined
+    if (declaredSize !== undefined && declaredSize > maximumBytes) return yield* Effect.fail(tooLarge())
+    let body = Buffer.allocUnsafe(Math.min(maximumBytes, declaredSize || 64 * 1024))
+    let size = 0
+    yield* Stream.runForEach(response.stream, (chunk) => {
+      if (chunk.byteLength === 0) return Effect.void
+      if (size + chunk.byteLength > maximumBytes) return Effect.fail(tooLarge())
+      if (size + chunk.byteLength > body.byteLength) {
+        const grown = Buffer.allocUnsafe(Math.min(maximumBytes, Math.max(size + chunk.byteLength, body.byteLength * 2)))
+        body.copy(grown, 0, 0, size)
+        body = grown
+      }
+      body.set(chunk, size)
+      size += chunk.byteLength
+      return Effect.void
+    })
+    return body.subarray(0, size)
+  })

packages/core/src/tool/read-filesystem.ts

@@ -13,23 +13,61 @@ export const MAX_MEDIA_INGEST_BYTES = 20 * 1024 * 1024
 const MAX_LINE_LENGTH = 2_000
 const MAX_LINE_SUFFIX = `... (line truncated to ${MAX_LINE_LENGTH} chars)`
 
-export class BinaryFileError extends Error {
-  constructor(readonly resource: string) {
-    super(`Cannot read binary file: ${resource}`)
-    this.name = "BinaryFileError"
+export class BinaryFileError extends Schema.TaggedErrorClass<BinaryFileError>()("ReadTool.BinaryFileError", {
+  resource: Schema.String,
+}) {
+  override get message() {
+    return `Cannot read binary file: ${this.resource}`
   }
 }
 
-export class MediaIngestLimitError extends Error {
-  constructor(
-    readonly resource: string,
-    readonly maximumBytes: number,
-  ) {
-    super(`Media exceeds ${maximumBytes} byte ingestion limit: ${resource}`)
-    this.name = "MediaIngestLimitError"
+export class MediaIngestLimitError extends Schema.TaggedErrorClass<MediaIngestLimitError>()(
+  "ReadTool.MediaIngestLimitError",
+  {
+    resource: Schema.String,
+    maximumBytes: Schema.Number,
+  },
+) {
+  override get message() {
+    return `Media exceeds ${this.maximumBytes} byte ingestion limit: ${this.resource}`
   }
 }
 
+export class MalformedUtf8Error extends Schema.TaggedErrorClass<MalformedUtf8Error>()("ReadTool.MalformedUtf8Error", {
+  resource: Schema.String,
+}) {
+  override get message() {
+    return `File is not valid UTF-8: ${this.resource}`
+  }
+}
+
+export class OffsetOutOfRangeError extends Schema.TaggedErrorClass<OffsetOutOfRangeError>()(
+  "ReadTool.OffsetOutOfRangeError",
+  { offset: Schema.Number },
+) {
+  override get message() {
+    return `Offset ${this.offset} is out of range`
+  }
+}
+
+export class PathKindError extends Schema.TaggedErrorClass<PathKindError>()("ReadTool.PathKindError", {
+  resource: Schema.String,
+  expected: Schema.Literals(["a file", "a file or directory"]),
+}) {
+  override get message() {
+    return `Path is not ${this.expected}: ${this.resource}`
+  }
+}
+
+export type InspectError = FSUtil.Error | PathKindError
+export type ReadError =
+  | FSUtil.Error
+  | BinaryFileError
+  | MediaIngestLimitError
+  | MalformedUtf8Error
+  | OffsetOutOfRangeError
+  | PathKindError
+
 export const PageInput = Schema.Struct({
   offset: PositiveInt.pipe(Schema.optional),
   limit: PositiveInt.check(Schema.isLessThanOrEqualTo(MAX_READ_LINES)).pipe(Schema.optional),
@@ -52,13 +90,13 @@ export class ListPage extends Schema.Class<ListPage>("ReadTool.ListPage")({
 }) {}
 
 export interface Interface {
-  readonly inspect: (path: AbsolutePath) => Effect.Effect<"file" | "directory">
+  readonly inspect: (path: AbsolutePath) => Effect.Effect<"file" | "directory", InspectError>
   readonly read: (
     path: AbsolutePath,
     resource: string,
     page?: PageInput,
-  ) => Effect.Effect<FileSystem.Content | TextPage>
-  readonly list: (path: AbsolutePath, page?: PageInput) => Effect.Effect<ListPage>
+  ) => Effect.Effect<FileSystem.Content | TextPage, ReadError>
+  readonly list: (path: AbsolutePath, page?: PageInput) => Effect.Effect<ListPage, FSUtil.Error>
 }
 
 export class Service extends Context.Service<Service, Interface>()("@opencode/ReadToolFileSystem") {}
@@ -111,11 +149,21 @@ const binary = (resource: string, bytes: Uint8Array) => {
   }
   return nonPrintable / bytes.length > 0.3
 }
+const decodeUtf8 = (resource: string, decoder: TextDecoder, bytes?: Uint8Array) =>
+  Effect.try({
+    try: () => decoder.decode(bytes, { stream: bytes !== undefined }),
+    catch: (error) => {
+      if (error instanceof TypeError) return new MalformedUtf8Error({ resource })
+      throw error
+    },
+  })
+const decodeChunk = (resource: string, decoder: TextDecoder, bytes: Uint8Array) =>
+  bytes.includes(0) ? Effect.fail(new BinaryFileError({ resource })) : decodeUtf8(resource, decoder, bytes)
 
 export const inspect = Effect.fn("ReadTool.inspect")(function* (fs: FSUtil.Interface, input: string) {
-  const info = yield* fs.stat(input).pipe(Effect.orDie)
+  const info = yield* fs.stat(input)
   const type = info.type === "File" ? "file" : info.type === "Directory" ? "directory" : undefined
-  if (!type) return yield* Effect.die(new Error("Path is not a file or directory"))
+  if (!type) return yield* Effect.fail(new PathKindError({ resource: input, expected: "a file or directory" }))
   return type
 })
 
@@ -125,32 +173,30 @@ export const read = Effect.fn("ReadTool.read")(function* (
   resource: string,
   page: PageInput = {},
 ) {
-  const real = yield* fs.realPath(input).pipe(Effect.orDie)
+  const real = yield* fs.realPath(input)
   return yield* Effect.scoped(
     Effect.gen(function* () {
-      const file = yield* fs.open(real, { flag: "r" }).pipe(Effect.orDie)
-      const info = yield* file.stat.pipe(Effect.orDie)
-      if (info.type !== "File") return yield* Effect.die(new Error("Path is not a file"))
+      const file = yield* fs.open(real, { flag: "r" })
+      const info = yield* file.stat
+      if (info.type !== "File") return yield* Effect.fail(new PathKindError({ resource, expected: "a file" }))
       const first = Option.getOrElse(
-        yield* file.readAlloc(Math.min(64 * 1024, Number(info.size) || 4 * 1024)).pipe(Effect.orDie),
+        yield* file.readAlloc(Math.min(64 * 1024, Number(info.size) || 4 * 1024)),
         () => new Uint8Array(),
       )
       const mime = imageMime(first)
       if (mime) {
         if (info.size > MAX_MEDIA_INGEST_BYTES)
-          return yield* Effect.die(new MediaIngestLimitError(resource, MAX_MEDIA_INGEST_BYTES))
+          return yield* Effect.fail(new MediaIngestLimitError({ resource, maximumBytes: MAX_MEDIA_INGEST_BYTES }))
         const chunks = [first]
         let total = first.length
         while (total <= MAX_MEDIA_INGEST_BYTES) {
-          const chunk = yield* file
-            .readAlloc(Math.min(64 * 1024, MAX_MEDIA_INGEST_BYTES + 1 - total))
-            .pipe(Effect.orDie)
+          const chunk = yield* file.readAlloc(Math.min(64 * 1024, MAX_MEDIA_INGEST_BYTES + 1 - total))
           if (Option.isNone(chunk)) break
           chunks.push(chunk.value)
           total += chunk.value.length
         }
         if (total > MAX_MEDIA_INGEST_BYTES)
-          return yield* Effect.die(new MediaIngestLimitError(resource, MAX_MEDIA_INGEST_BYTES))
+          return yield* Effect.fail(new MediaIngestLimitError({ resource, maximumBytes: MAX_MEDIA_INGEST_BYTES }))
         return {
           uri: pathToFileURL(real).href,
           name: path.basename(real),
@@ -162,19 +208,19 @@ export const read = Effect.fn("ReadTool.read")(function* (
           mime,
         }
       }
-      if (startsWith(first, [0x25, 0x50, 0x44, 0x46]) || binary(resource, first))
-        return yield* Effect.die(new BinaryFileError(resource))
+      if (startsWith(first, [0x25, 0x50, 0x44, 0x46]) || extensions.has(path.extname(resource).toLowerCase()))
+        return yield* Effect.fail(new BinaryFileError({ resource }))
       const paged = info.size > MAX_READ_BYTES || page.offset !== undefined || page.limit !== undefined
       if (!paged) {
+        if (binary(resource, first)) return yield* Effect.fail(new BinaryFileError({ resource }))
         const decoder = new TextDecoder("utf-8", { fatal: true })
-        const text = [yield* Effect.sync(() => decoder.decode(first, { stream: true }))]
+        const text = [yield* decodeUtf8(resource, decoder, first)]
         while (true) {
-          const chunk = yield* file.readAlloc(64 * 1024).pipe(Effect.orDie)
+          const chunk = yield* file.readAlloc(64 * 1024)
           if (Option.isNone(chunk)) break
-          if (chunk.value.includes(0)) return yield* Effect.die(new BinaryFileError(resource))
-          text.push(yield* Effect.sync(() => decoder.decode(chunk.value, { stream: true })))
+          text.push(yield* decodeChunk(resource, decoder, chunk.value))
         }
-        text.push(yield* Effect.sync(() => decoder.decode()))
+        text.push(yield* decodeUtf8(resource, decoder))
         return {
           uri: pathToFileURL(real).href,
           name: path.basename(real),
@@ -191,34 +237,29 @@ export const read = Effect.fn("ReadTool.read")(function* (
       let discard = false
       let line = 1
       let bytes = 0
-      let found = false
-      let truncated = false
       let next: number | undefined
       const append = (input: string) => {
         if (line < offset) {
           line++
-          return
+          return true
         }
         if (lines.length >= limit || bytes >= MAX_READ_BYTES) {
-          truncated = true
-          next ??= line++
-          return
+          next = line
+          return false
         }
-        found = true
         const text = input.length > MAX_LINE_LENGTH ? input.slice(0, MAX_LINE_LENGTH) + MAX_LINE_SUFFIX : input
         const size = Buffer.byteLength(text, "utf-8") + (lines.length > 0 ? 1 : 0)
         if (bytes + size > MAX_READ_BYTES) {
-          truncated = true
-          next ??= line++
-          return
+          next = line
+          return false
         }
         lines.push(text)
         bytes += size
         line++
+        return true
       }
-      const consume = (chunk: Uint8Array) => {
-        if (chunk.includes(0)) throw new BinaryFileError(resource)
-        let text = decoder.decode(chunk, { stream: true })
+      const consume = (input: string) => {
+        let text = input
         while (true) {
           const index = text.indexOf("\n")
           if (index === -1) {
@@ -235,25 +276,44 @@ export const read = Effect.fn("ReadTool.read")(function* (
           pending = ""
           discard = false
           text = text.slice(index + 1)
-          append(current.endsWith("\r") ? current.slice(0, -1) : current)
+          if (!append(current.endsWith("\r") ? current.slice(0, -1) : current)) return false
         }
+        return true
       }
-      yield* Effect.sync(() => consume(first))
-      while (true) {
-        const chunk = yield* file.readAlloc(64 * 1024).pipe(Effect.orDie)
+      const consumeChunk = Effect.fnUntraced(function* (chunk: Uint8Array) {
+        let start = 0
+        while (start < chunk.length) {
+          if (lines.length >= limit || bytes >= MAX_READ_BYTES) {
+            next = line
+            return false
+          }
+          const newline = chunk.indexOf(10, start)
+          const end = newline === -1 ? chunk.length : newline + 1
+          const segment = chunk.subarray(start, end)
+          if (binary(resource, segment)) return yield* Effect.fail(new BinaryFileError({ resource }))
+          if (!consume(yield* decodeUtf8(resource, decoder, segment))) return false
+          start = end
+        }
+        return true
+      })
+      let done = !(yield* consumeChunk(first))
+      while (!done) {
+        const chunk = yield* file.readAlloc(64 * 1024)
         if (Option.isNone(chunk)) break
-        yield* Effect.sync(() => consume(chunk.value))
+        done = !(yield* consumeChunk(chunk.value))
       }
-      const tail = yield* Effect.sync(() => decoder.decode())
-      if (!discard) pending += tail
-      if (pending) append(pending.endsWith("\r") ? pending.slice(0, -1) : pending)
-      if (!found && offset !== 1) return yield* Effect.die(new Error(`Offset ${offset} is out of range`))
+      if (!done) {
+        const tail = yield* decodeUtf8(resource, decoder)
+        if (!discard) pending += tail
+        if (pending) append(pending.endsWith("\r") ? pending.slice(0, -1) : pending)
+      }
+      if (lines.length === 0 && offset !== 1) return yield* Effect.fail(new OffsetOutOfRangeError({ offset }))
       return new TextPage({
         type: "text-page",
         content: lines.join("\n"),
         mime: FSUtil.mimeType(real),
         offset,
-        truncated,
+        truncated: next !== undefined,
         ...(next === undefined ? {} : { next }),
       })
     }),
@@ -261,8 +321,8 @@ export const read = Effect.fn("ReadTool.read")(function* (
 })
 
 export const list = Effect.fn("ReadTool.list")(function* (fs: FSUtil.Interface, input: string, page: PageInput = {}) {
-  const real = yield* fs.realPath(input).pipe(Effect.orDie)
-  const items = yield* fs.readDirectoryEntries(real).pipe(Effect.orDie)
+  const real = yield* fs.realPath(input)
+  const items = yield* fs.readDirectoryEntries(real)
   const offset = page.offset ?? 1
   const limit = Math.min(page.limit ?? MAX_READ_LINES, MAX_READ_LINES)
   const entries = yield* Effect.forEach(

packages/core/src/tool/read.ts

@@ -57,8 +57,8 @@ export const layer = Layer.effectDiscard(
               const selected = path.isAbsolute(input.path) ? path.dirname(absolute) : location.directory
               if (!path.isAbsolute(input.path) && !FSUtil.contains(location.directory, absolute))
                 return yield* Effect.die(new Error("Path escapes the allowed read root"))
-              const real = yield* fs.realPath(absolute).pipe(Effect.orDie)
-              const root = yield* fs.realPath(selected).pipe(Effect.orDie)
+              const real = yield* fs.realPath(absolute)
+              const root = yield* fs.realPath(selected)
               if (!FSUtil.contains(root, real))
                 return yield* Effect.die(new Error("Path escapes the allowed read root"))
               const resource = path.relative(root, real).replaceAll("\\", "/") || "."
@@ -83,7 +83,7 @@ export const layer = Layer.effectDiscard(
                   .pipe(Effect.catchTag("Image.ResizerUnavailableError", () => Effect.succeed(content)))
               }
               if ("encoding" in content && content.encoding === "base64")
-                return yield* Effect.fail(new ReadToolFileSystem.BinaryFileError(resource))
+                return yield* Effect.fail(new ReadToolFileSystem.BinaryFileError({ resource }))
               return content
             }).pipe(
               Effect.mapError((error) => {

packages/core/src/tool/webfetch.ts

@@ -1,11 +1,12 @@
 export * as WebFetchTool from "./webfetch"
 
 import { ToolFailure } from "@opencode-ai/llm"
-import { Duration, Effect, Layer, Schema, Stream } from "effect"
+import { Duration, Effect, Layer, Schema } from "effect"
 import { HttpClient, HttpClientRequest, HttpClientResponse } from "effect/unstable/http"
 import { Parser } from "htmlparser2"
 import TurndownService from "turndown"
 import { PermissionV2 } from "../permission"
+import { collectBoundedResponseBody } from "./http-body"
 import { Tool } from "./tool"
 import { Tools } from "./tools"
 
@@ -86,24 +87,11 @@ const execute = (http: HttpClient.HttpClient, url: string, format: Format, userA
   http.execute(request(url, format, userAgent)).pipe(Effect.flatMap(HttpClientResponse.filterStatusOk))
 
 const collectBody = (response: HttpClientResponse.HttpClientResponse) =>
-  Effect.gen(function* () {
-    const contentLength = response.headers["content-length"]
-    if (contentLength && Number.parseInt(contentLength, 10) > MAX_RESPONSE_BYTES) {
-      return yield* Effect.fail(new Error(`Response too large (exceeds ${MAX_RESPONSE_BYTES} byte limit)`))
-    }
-    const chunks: Uint8Array[] = []
-    let size = 0
-    yield* Stream.runForEach(response.stream, (chunk) =>
-      Effect.gen(function* () {
-        size += chunk.byteLength
-        if (size > MAX_RESPONSE_BYTES)
-          return yield* Effect.fail(new Error(`Response too large (exceeds ${MAX_RESPONSE_BYTES} byte limit)`))
-        chunks.push(chunk)
-        return undefined
-      }),
-    )
-    return Buffer.concat(chunks, size)
-  })
+  collectBoundedResponseBody(
+    response,
+    MAX_RESPONSE_BYTES,
+    () => new Error(`Response too large (exceeds ${MAX_RESPONSE_BYTES} byte limit)`),
+  )
 
 const mimeFrom = (contentType: string) => contentType.split(";", 1)[0]?.trim().toLowerCase() ?? ""
 const isImageAttachment = (mime: string) =>
@@ -171,12 +159,16 @@ export const layer = Layer.effectDiscard(
                   orElse: () => Effect.fail(new Error("Request timed out")),
                 }),
               )
-              const content = convert(new TextDecoder().decode(body), contentType, input.format)
+              const content = new TextDecoder().decode(body)
+              const output = yield* Effect.try({
+                try: () => convert(content, contentType, input.format),
+                catch: (error) => error,
+              })
               return {
                 url: input.url,
                 contentType,
                 format: input.format,
-                output: content,
+                output,
               }
             }).pipe(Effect.mapError(() => new ToolFailure({ message: `Unable to fetch ${input.url}` }))),
         }),

packages/core/src/tool/websearch.ts

@@ -9,6 +9,7 @@ import { PositiveInt } from "../schema"
 import { PermissionV2 } from "../permission"
 import { Tool } from "./tool"
 import { Tools } from "./tools"
+import { collectBoundedResponseBody } from "./http-body"
 import { checksum } from "../util/encode"
 
 export const name = "websearch"
@@ -164,10 +165,12 @@ const callMcp = <F extends Schema.Struct.Fields>(
     )
     return yield* Effect.gen(function* () {
       const response = yield* HttpClient.filterStatusOk(http).execute(request)
-      const body = yield* response.text
-      if (Buffer.byteLength(body, "utf8") > MAX_RESPONSE_BYTES)
-        return yield* Effect.fail(new Error(`${tool} response exceeded ${MAX_RESPONSE_BYTES} bytes`))
-      return yield* parseResponse(body)
+      const body = yield* collectBoundedResponseBody(
+        response,
+        MAX_RESPONSE_BYTES,
+        () => new Error(`${tool} response exceeded ${MAX_RESPONSE_BYTES} bytes`),
+      )
+      return yield* parseResponse(body.toString("utf8"))
     }).pipe(
       Effect.timeoutOrElse({
         duration: Duration.seconds(25),

packages/core/src/v1/config/migrate.ts

@@ -215,8 +215,23 @@ function migrateModel(info: typeof ConfigProviderV1.Model.Type, packageName?: st
       : []),
   ]
   const capabilities =
-    info.tool_call !== undefined || info.modalities?.input !== undefined || info.modalities?.output !== undefined
-      ? { tools: info.tool_call ?? false, input: info.modalities?.input ?? [], output: info.modalities?.output ?? [] }
+    info.attachment !== undefined ||
+    info.tool_call !== undefined ||
+    info.modalities?.input !== undefined ||
+    info.modalities?.output !== undefined
+      ? {
+          ...(info.tool_call === undefined ? {} : { tools: info.tool_call }),
+          ...(info.modalities?.input !== undefined
+            ? { input: info.modalities.input }
+            : info.attachment !== undefined
+              ? { input: info.attachment ? ["text", "image"] : ["text"] }
+              : {}),
+          ...(info.modalities?.output !== undefined
+            ? { output: info.modalities.output }
+            : info.attachment !== undefined
+              ? { output: ["text"] }
+              : {}),
+        }
       : undefined
   return {
     family: info.family,

packages/core/src/v1/session.ts

@@ -502,7 +502,7 @@ export type WithParts = {
 }
 
 const options = {
-  sync: {
+  durable: {
     aggregate: "sessionID",
     version: 1,
   },

packages/core/test/catalog.test.ts

@@ -11,7 +11,11 @@ import { ProviderV2 } from "@opencode-ai/core/provider"
 import { AbsolutePath } from "@opencode-ai/core/schema"
 import { location } from "./fixture/location"
 import { testEffect } from "./lib/effect"
-import { required } from "./plugin/provider-helper"
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
 
 const locationLayer = Layer.succeed(
   Location.Service,
@@ -21,12 +25,7 @@ const it = testEffect(
   Catalog.locationLayer.pipe(
     Layer.provideMerge(EventV2.defaultLayer),
     Layer.provideMerge(locationLayer),
-    Layer.provideMerge(
-      Layer.mock(Credential.Service)({
-        all: () => Effect.succeed([]),
-        list: () => Effect.succeed([]),
-      }),
-    ),
+    Layer.provideMerge(Credential.defaultLayer),
   ),
 )
 
@@ -48,38 +47,30 @@ describe("CatalogV2", () => {
 
   it.effect("derives availability from active credentials without changing provider state", () => {
     const integrationID = Integration.ID.make("test")
-    const first = {
-      id: Credential.ID.create(),
-      integrationID,
-      label: "First",
-      value: new Credential.Key({ type: "key", key: "first", metadata: { tenant: "one" } }),
-    }
-    const second = {
-      id: Credential.ID.create(),
-      integrationID,
-      label: "Second",
-      value: new Credential.Key({ type: "key", key: "second", metadata: { tenant: "two" } }),
-    }
-    let active = first
     const layer = Catalog.locationLayer.pipe(
       Layer.fresh,
       Layer.provideMerge(EventV2.defaultLayer),
       Layer.provideMerge(locationLayer),
-      Layer.provideMerge(
-        Layer.mock(Credential.Service)({
-          all: () => Effect.sync(() => [active]),
-          list: () => Effect.sync(() => [active]),
-        }),
-      ),
+      Layer.provideMerge(Credential.defaultLayer.pipe(Layer.fresh)),
     )
 
     return Effect.gen(function* () {
       const catalog = yield* Catalog.Service
+      const credentials = yield* Credential.Service
       yield* catalog.transform((editor) => editor.provider.update(ProviderV2.ID.make("test"), () => {}))
+      yield* credentials.create({
+        integrationID,
+        label: "First",
+        value: new Credential.Key({ type: "key", key: "first", metadata: { tenant: "one" } }),
+      })
 
       expect((yield* catalog.provider.available()).map((provider) => provider.id)).toEqual([ProviderV2.ID.make("test")])
       expect(required(yield* catalog.provider.get(ProviderV2.ID.make("test"))).request.body).toEqual({})
-      active = second
+      yield* credentials.create({
+        integrationID,
+        label: "Second",
+        value: new Credential.Key({ type: "key", key: "second", metadata: { tenant: "two" } }),
+      })
       expect((yield* catalog.provider.available()).map((provider) => provider.id)).toEqual([ProviderV2.ID.make("test")])
       expect(required(yield* catalog.provider.get(ProviderV2.ID.make("test"))).request.body).toEqual({})
     }).pipe(Effect.provide(layer))

packages/core/test/config/config.test.ts

@@ -116,6 +116,34 @@ describe("Config", () => {
     }),
   )
 
+  it.effect("migrates v1 custom model capability overrides without replacing unspecified fields", () =>
+    Effect.sync(() => {
+      const migrated = ConfigMigrateV1.migrate({
+        provider: {
+          custom: {
+            models: {
+              default: { tool_call: true },
+              text: { attachment: false },
+              explicit: { modalities: { input: ["audio"], output: ["audio"] } },
+            },
+          },
+        },
+      })
+
+      expect(migrated.providers?.custom?.models?.default?.capabilities).toEqual({
+        tools: true,
+      })
+      expect(migrated.providers?.custom?.models?.text?.capabilities).toEqual({
+        input: ["text"],
+        output: ["text"],
+      })
+      expect(migrated.providers?.custom?.models?.explicit?.capabilities).toEqual({
+        input: ["audio"],
+        output: ["audio"],
+      })
+    }),
+  )
+
   it.effect("migrates v1 command configuration", () =>
     Effect.sync(() => {
       expect(

packages/core/test/config/provider.test.ts

@@ -1,14 +1,53 @@
 import { describe, expect } from "bun:test"
-import { Effect, Option, Schema } from "effect"
+import { Effect, Schema } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
 import { Config } from "@opencode-ai/core/config"
 import { ConfigProviderPlugin } from "@opencode-ai/core/config/plugin/provider"
+import { ConfigMigrateV1 } from "@opencode-ai/core/v1/config/migrate"
 import { Integration } from "@opencode-ai/core/integration"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { it, required, withEnv } from "../plugin/provider-helper"
-import { catalogHost, host, integrationHost } from "../plugin/host"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "../plugin/fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* (config: Config.Interface) {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({
+    ...ConfigProviderPlugin.Plugin,
+    effect: ConfigProviderPlugin.Plugin.effect(host).pipe(Effect.provideService(Config.Service, config)),
+  })
+})
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, effect: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    effect,
+    (previous) =>
+      Effect.sync(() =>
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        }),
+      ),
+  )
+}
 
 function request(headers: Record<string, string>, variant?: string) {
   return {
@@ -23,8 +62,6 @@ describe("ConfigProviderPlugin.Plugin", () => {
   it.effect("partitions existing model variant bodies without changing config shape", () =>
     Effect.gen(function* () {
       const catalog = yield* Catalog.Service
-      const integrations = yield* Integration.Service
-      const plugin = yield* PluginV2.Service
       const providerID = ProviderV2.ID.opencode
       const modelID = ModelV2.ID.make("alpha-gpt-next")
       const config = Config.Service.of({
@@ -57,14 +94,7 @@ describe("ConfigProviderPlugin.Plugin", () => {
           ]),
       })
 
-      yield* plugin.add({
-        ...ConfigProviderPlugin.Plugin,
-        effect: ConfigProviderPlugin.Plugin.effect(
-          host({ catalog: catalogHost(catalog), integration: integrationHost(integrations) }),
-        ).pipe(
-          Effect.provideService(Config.Service, config),
-        ),
-      })
+      yield* addPlugin(config)
 
       const model = required(yield* catalog.model.get(providerID, modelID))
       expect(model.variants).toMatchObject([
@@ -84,8 +114,6 @@ describe("ConfigProviderPlugin.Plugin", () => {
   it.effect("uses the effective provider package across layered config", () =>
     Effect.gen(function* () {
       const catalog = yield* Catalog.Service
-      const integrations = yield* Integration.Service
-      const plugin = yield* PluginV2.Service
       const providerID = ProviderV2.ID.opencode
       const modelID = ModelV2.ID.make("alpha-gpt-next")
       const config = Config.Service.of({
@@ -118,14 +146,7 @@ describe("ConfigProviderPlugin.Plugin", () => {
           ]),
       })
 
-      yield* plugin.add({
-        ...ConfigProviderPlugin.Plugin,
-        effect: ConfigProviderPlugin.Plugin.effect(
-          host({ catalog: catalogHost(catalog), integration: integrationHost(integrations) }),
-        ).pipe(
-          Effect.provideService(Config.Service, config),
-        ),
-      })
+      yield* addPlugin(config)
 
       const model = required(yield* catalog.model.get(providerID, modelID))
       expect(model.variants[0]).toMatchObject({
@@ -141,7 +162,6 @@ describe("ConfigProviderPlugin.Plugin", () => {
       Effect.gen(function* () {
         const catalog = yield* Catalog.Service
         const integrations = yield* Integration.Service
-        const plugin = yield* PluginV2.Service
         const providerID = ProviderV2.ID.make("custom")
         const modelID = ModelV2.ID.make("chat")
         const config = Config.Service.of({
@@ -221,18 +241,13 @@ describe("ConfigProviderPlugin.Plugin", () => {
             ]),
         })
 
-        yield* plugin.add({
-          ...ConfigProviderPlugin.Plugin,
-          effect: ConfigProviderPlugin.Plugin.effect(
-            host({ catalog: catalogHost(catalog), integration: integrationHost(integrations) }),
-          ).pipe(
-            Effect.provideService(Config.Service, config),
-          ),
-        })
+        yield* addPlugin(config)
 
         const provider = required(yield* catalog.provider.get(providerID))
         const model = required(yield* catalog.model.get(providerID, modelID))
-        expect((yield* catalog.model.default())?.id).toBe(ModelV2.ID.make("default"))
+        const defaultModel = required(yield* catalog.model.default())
+        expect(defaultModel.id).toBe(ModelV2.ID.make("default"))
+        expect(defaultModel.capabilities).toEqual({ tools: false, input: ["text", "image"], output: ["text"] })
         expect(provider.name).toBe("Renamed")
         expect((yield* integrations.get(Integration.ID.make("custom")))?.methods).toContainEqual({
           type: "env",
@@ -259,4 +274,67 @@ describe("ConfigProviderPlugin.Plugin", () => {
       }),
     ),
   )
+
+  it.effect("lowers a migrated attachment override into modalities", () =>
+    Effect.gen(function* () {
+      const catalog = yield* Catalog.Service
+      const providerID = ProviderV2.ID.make("custom")
+      const modelID = ModelV2.ID.make("chat")
+      yield* catalog.transform((catalog) =>
+        catalog.model.update(providerID, modelID, (model) => {
+          model.capabilities = { tools: true, input: ["text", "image", "audio"], output: ["text", "audio"] }
+        }),
+      )
+      const config = Config.Service.of({
+        entries: () =>
+          Effect.succeed([
+            new Config.Document({
+              type: "document",
+              info: decode(
+                ConfigMigrateV1.migrate({
+                  provider: { custom: { models: { chat: { attachment: false } } } },
+                }),
+              ),
+            }),
+          ]),
+      })
+
+      yield* addPlugin(config)
+
+      expect(required(yield* catalog.model.get(providerID, modelID)).capabilities).toEqual({
+        tools: true,
+        input: ["text"],
+        output: ["text"],
+      })
+    }),
+  )
+
+  it.effect("defaults a migrated custom model with attachment disabled to text only", () =>
+    Effect.gen(function* () {
+      const catalog = yield* Catalog.Service
+      const providerID = ProviderV2.ID.make("custom")
+      const modelID = ModelV2.ID.make("chat")
+      const config = Config.Service.of({
+        entries: () =>
+          Effect.succeed([
+            new Config.Document({
+              type: "document",
+              info: decode(
+                ConfigMigrateV1.migrate({
+                  provider: { custom: { models: { chat: { attachment: false } } } },
+                }),
+              ),
+            }),
+          ]),
+      })
+
+      yield* addPlugin(config)
+
+      expect(required(yield* catalog.model.get(providerID, modelID)).capabilities).toEqual({
+        tools: false,
+        input: ["text"],
+        output: ["text"],
+      })
+    }),
+  )
 })

packages/core/test/credential.test.ts

@@ -1,49 +1,35 @@
-import path from "path"
 import { describe, expect } from "bun:test"
-import { Effect, Layer } from "effect"
+import { Effect } from "effect"
 import { Credential } from "@opencode-ai/core/credential"
-import { Database } from "@opencode-ai/core/database/database"
 import { Integration } from "@opencode-ai/core/integration"
-import { tmpdir } from "./fixture/tmpdir"
-import { it } from "./lib/effect"
+import { testEffect } from "./lib/effect"
 
-function layer(directory: string) {
-  return Credential.layer.pipe(
-    Layer.provide(Database.layerFromPath(path.join(directory, "credential.db")).pipe(Layer.fresh)),
-  )
-}
+const it = testEffect(Credential.defaultLayer)
 
 describe("Credential", () => {
-  it.live("stores, updates, lists, and removes credentials", () =>
-    Effect.acquireRelease(
-      Effect.promise(() => tmpdir()),
-      (tmp) => Effect.promise(() => tmp[Symbol.asyncDispose]()),
-    ).pipe(
-      Effect.flatMap((tmp) =>
-        Effect.gen(function* () {
-          const credentials = yield* Credential.Service
-          const integrationID = Integration.ID.make("openai")
-          const created = yield* credentials.create({
-            integrationID,
-            label: "Work",
-            value: new Credential.Key({ type: "key", key: "secret" }),
-          })
+  it.effect("stores, updates, lists, and removes credentials", () =>
+    Effect.gen(function* () {
+      const credentials = yield* Credential.Service
+      const integrationID = Integration.ID.make("openai")
+      const created = yield* credentials.create({
+        integrationID,
+        label: "Work",
+        value: new Credential.Key({ type: "key", key: "secret" }),
+      })
 
-          expect(yield* credentials.list(integrationID)).toEqual([created])
-          yield* credentials.update(created.id, { label: "Personal" })
-          expect((yield* credentials.list(integrationID))[0]?.label).toBe("Personal")
+      expect(yield* credentials.list(integrationID)).toEqual([created])
+      yield* credentials.update(created.id, { label: "Personal" })
+      expect((yield* credentials.list(integrationID))[0]?.label).toBe("Personal")
 
-          const replacement = yield* credentials.create({
-            integrationID,
-            label: "Replacement",
-            value: new Credential.Key({ type: "key", key: "replacement" }),
-          })
-          expect(yield* credentials.list(integrationID)).toEqual([replacement])
+      const replacement = yield* credentials.create({
+        integrationID,
+        label: "Replacement",
+        value: new Credential.Key({ type: "key", key: "replacement" }),
+      })
+      expect(yield* credentials.list(integrationID)).toEqual([replacement])
 
-          yield* credentials.remove(replacement.id)
-          expect(yield* credentials.list(integrationID)).toEqual([])
-        }).pipe(Effect.provide(layer(tmp.path))),
-      ),
-    ),
+      yield* credentials.remove(replacement.id)
+      expect(yield* credentials.list(integrationID)).toEqual([])
+    }),
   )
 })

packages/core/test/database-migration.test.ts

@@ -14,6 +14,8 @@ import sessionMessageProjectionOrderMigration from "@opencode-ai/core/database/m
 import eventSourcedSessionInputMigration from "@opencode-ai/core/database/migration/20260604172448_event_sourced_session_input"
 import contextEpochAgentMigration from "@opencode-ai/core/database/migration/20260605042240_add_context_epoch_agent"
 import simplifyIntegrationCredentialsMigration from "@opencode-ai/core/database/migration/20260611192811_lush_chimera"
+import resetV2SessionStateMigration from "@opencode-ai/core/database/migration/20260622170816_reset_v2_session_state"
+import { EventV2 } from "@opencode-ai/core/event"
 import { ProjectV2 } from "@opencode-ai/core/project"
 import { ProjectTable } from "@opencode-ai/core/project/sql"
 import { AbsolutePath } from "@opencode-ai/core/schema"
@@ -22,6 +24,8 @@ import { SessionTable } from "@opencode-ai/core/session/sql"
 import sessionMetadataMigration from "@opencode-ai/core/database/migration/20260511173437_session-metadata"
 import type { SqlClient as SqlClientService } from "effect/unstable/sql/SqlClient"
 import { Database } from "@opencode-ai/core/database/database"
+import { SessionProjector } from "@opencode-ai/core/session/projector"
+import { SessionV1 } from "@opencode-ai/core/v1/session"
 import { tmpdir } from "./fixture/tmpdir"
 
 const run = <A, E>(effect: Effect.Effect<A, E, SqlClientService>) =>
@@ -71,9 +75,9 @@ describe("DatabaseMigration", () => {
         ).toEqual({ name: "session_context_epoch" })
         expect(
           yield* db.get(
-            sql`SELECT name, dflt_value FROM pragma_table_info('session_context_epoch') WHERE name = 'agent'`,
+            sql`SELECT name FROM pragma_table_info('session_context_epoch') WHERE name IN ('agent', 'replacement_seq', 'revision')`,
           ),
-        ).toEqual({ name: "agent", dflt_value: "'build'" })
+        ).toBeUndefined()
         expect(yield* db.get(sql`SELECT count(*) as count FROM migration`)).toEqual({ count: migrations.length })
         expect(
           yield* db.all(
@@ -226,6 +230,94 @@ describe("DatabaseMigration", () => {
     )
   })
 
+  test("preserves canonical V1 state and restarts its event stream", async () => {
+    await run(
+      Effect.gen(function* () {
+        const db = yield* makeDb
+        yield* db.run(sql`PRAGMA foreign_keys = ON`)
+        yield* DatabaseMigration.apply(db)
+        yield* db.run(
+          sql`INSERT INTO project (id, worktree, time_created, time_updated, sandboxes) VALUES ('global', '/project', 1, 1, '[]')`,
+        )
+        yield* db.run(
+          sql`INSERT INTO workspace (id, type, project_id, time_used) VALUES ('workspace', 'local', 'global', 1)`,
+        )
+        yield* db.run(
+          sql`INSERT INTO session (id, project_id, workspace_id, slug, directory, title, version, time_created, time_updated) VALUES ('session', 'global', 'workspace', 'session', '/project', 'Before', 'test', 1, 1)`,
+        )
+        yield* db.run(
+          sql`INSERT INTO message (id, session_id, time_created, time_updated, data) VALUES ('message', 'session', 1, 1, '{}')`,
+        )
+        yield* db.run(
+          sql`INSERT INTO part (id, message_id, session_id, time_created, time_updated, data) VALUES ('part', 'message', 'session', 1, 1, '{}')`,
+        )
+        yield* db.run(sql`INSERT INTO event_sequence (aggregate_id, seq) VALUES ('session', 9)`)
+        yield* db.run(
+          sql`INSERT INTO event (id, aggregate_id, seq, type, data) VALUES ('event', 'session', 9, 'session.updated.1', '{}')`,
+        )
+        yield* db.run(
+          sql`INSERT INTO session_input (id, session_id, prompt, delivery, admitted_seq, time_created) VALUES ('input', 'session', '{}', 'steer', 9, 1)`,
+        )
+        yield* db.run(
+          sql`INSERT INTO session_message (id, session_id, type, seq, time_created, time_updated, data) VALUES ('projected', 'session', 'user', 9, 1, 1, '{}')`,
+        )
+        yield* db.run(
+          sql`INSERT INTO session_context_epoch (session_id, baseline, snapshot, baseline_seq) VALUES ('session', 'baseline', '{}', 9)`,
+        )
+        yield* db.run(sql`DELETE FROM migration WHERE id = ${resetV2SessionStateMigration.id}`)
+        yield* DatabaseMigration.applyOnly(db, [resetV2SessionStateMigration])
+
+        const database = Layer.succeed(Database.Service, { db })
+        const events = EventV2.layer.pipe(Layer.provide(database))
+        yield* EventV2.Service.use((service) =>
+          service.publish(SessionV1.Event.Updated, {
+            sessionID: SessionSchema.ID.make("session"),
+            info: {
+              id: SessionSchema.ID.make("session"),
+              slug: "session",
+              projectID: ProjectV2.ID.global,
+              directory: "/project",
+              title: "After",
+              version: "test",
+              time: { created: 1, updated: 2 },
+            },
+          }),
+        ).pipe(
+          Effect.provide(
+            Layer.merge(events, SessionProjector.layer.pipe(Layer.provide(events), Layer.provide(database))),
+          ),
+        )
+
+        expect(
+          yield* db.get(sql`
+            SELECT
+              (SELECT title FROM session WHERE id = 'session') AS title,
+              (SELECT workspace_id FROM session WHERE id = 'session') AS workspaceID,
+              (SELECT COUNT(*) FROM message WHERE id = 'message') AS messages,
+              (SELECT COUNT(*) FROM part WHERE id = 'part') AS parts,
+              (SELECT COUNT(*) FROM workspace) AS workspaces,
+              (SELECT COUNT(*) FROM session_input) AS sessionInputs,
+              (SELECT COUNT(*) FROM session_message) AS sessionMessages,
+              (SELECT COUNT(*) FROM session_context_epoch) AS contextEpochs,
+              (SELECT seq FROM event_sequence WHERE aggregate_id = 'session') AS seq,
+              (SELECT type FROM event WHERE aggregate_id = 'session') AS eventType
+          `),
+        ).toEqual({
+          title: "After",
+          workspaceID: null,
+          messages: 1,
+          parts: 1,
+          workspaces: 0,
+          sessionInputs: 0,
+          sessionMessages: 0,
+          contextEpochs: 0,
+          seq: 0,
+          eventType: "session.updated.1",
+        })
+      }),
+    )
+  })
+
   test("resets incompatible projected Session messages before adding sequence order", async () => {
     await run(
       Effect.gen(function* () {

packages/core/test/event.test.ts

@@ -30,7 +30,7 @@ const Message = EventV2.define({
 
 const SyncMessage = EventV2.define({
   type: "test.sync",
-  sync: {
+  durable: {
     version: 1,
     aggregate: "id",
   },
@@ -42,7 +42,7 @@ const SyncMessage = EventV2.define({
 
 const SyncSent = EventV2.define({
   type: "test.sent",
-  sync: {
+  durable: {
     version: 1,
     aggregate: "messageID",
   },
@@ -61,7 +61,7 @@ const GlobalMessage = EventV2.define({
 
 const VersionedMessage = EventV2.define({
   type: "test.versioned",
-  sync: {
+  durable: {
     version: 2,
     aggregate: "id",
   },
@@ -73,7 +73,7 @@ const VersionedMessage = EventV2.define({
 
 const SyncTimestamp = EventV2.define({
   type: "test.timestamp",
-  sync: {
+  durable: {
     version: 1,
     aggregate: "id",
   },
@@ -132,7 +132,7 @@ describe("EventV2", () => {
       const event = yield* events.publish(VersionedMessage, { id: "one", text: "hello" })
 
       expect(event.type).toBe("test.versioned")
-      expect(event.version).toBe(2)
+      expect(event.durable?.version).toBe(2)
     }),
   )
 
@@ -146,12 +146,12 @@ describe("EventV2", () => {
     Effect.sync(() => {
       const latest = EventV2.define({
         type: "test.out-of-order",
-        sync: { version: 2, aggregate: "id" },
+        durable: { version: 2, aggregate: "id" },
         schema: { id: Schema.String },
       })
       EventV2.define({
         type: "test.out-of-order",
-        sync: { version: 1, aggregate: "id" },
+        durable: { version: 1, aggregate: "id" },
         schema: { id: Schema.String },
       })
 
@@ -190,7 +190,7 @@ describe("EventV2", () => {
     }),
   )
 
-  it.effect("commits local operational state inside a new synchronized event transaction", () =>
+  it.effect("commits local operational state inside a new durable event transaction", () =>
     Effect.gen(function* () {
       const events = yield* EventV2.Service
       const received = new Array<string>()
@@ -207,7 +207,7 @@ describe("EventV2", () => {
     }),
   )
 
-  it.effect("rolls back the synchronized event and projector when the local commit fails", () =>
+  it.effect("rolls back the durable event and projector when the local commit fails", () =>
     Effect.gen(function* () {
       const events = yield* EventV2.Service
       const { db } = yield* Database.Service
@@ -236,7 +236,7 @@ describe("EventV2", () => {
       const events = yield* EventV2.Service
       const exit = yield* events.publish(Message, { text: "hello" }, { commit: () => Effect.void }).pipe(Effect.exit)
 
-      expect(String(exit)).toContain("Local commit hooks require a synchronized event")
+      expect(String(exit)).toContain("Local commit hooks require a durable event")
     }),
   )
 
@@ -290,7 +290,6 @@ describe("EventV2", () => {
     Effect.gen(function* () {
       const events = yield* EventV2.Service
       const received = new Array<string>()
-      yield* events.sync(() => Effect.die("sync defect"))
       yield* events.listen(() => {
         throw new Error("listener defect")
       })
@@ -303,7 +302,7 @@ describe("EventV2", () => {
       const event = yield* events.publish(SyncMessage, { id: "one", text: "hello" })
 
       expect(received).toEqual([SyncMessage.type])
-      expect(event.seq).toBeNumber()
+      expect(event.durable?.seq).toBeNumber()
     }),
   )
 
@@ -336,49 +335,7 @@ describe("EventV2", () => {
     }),
   )
 
-  it.effect("does not synchronize live-only events", () =>
-    Effect.gen(function* () {
-      const events = yield* EventV2.Service
-      const synchronized = new Array<string>()
-      const unsubscribe = yield* events.sync((event) =>
-        Effect.sync(() => {
-          synchronized.push(event.type)
-        }),
-      )
-      yield* Effect.addFinalizer(() => unsubscribe)
-
-      yield* events.publish(Message, { text: "live only" })
-      yield* events.publish(SyncMessage, { id: "one", text: "durable" })
-
-      expect(synchronized).toEqual([SyncMessage.type])
-    }),
-  )
-
-  it.effect("synchronizes only after the durable event commits", () =>
-    Effect.gen(function* () {
-      const events = yield* EventV2.Service
-      const { db } = yield* Database.Service
-      const synchronized = new Array<boolean>()
-      yield* events.sync((event) =>
-        db
-          .select({ id: EventTable.id })
-          .from(EventTable)
-          .where(eq(EventTable.id, event.id))
-          .get()
-          .pipe(
-            Effect.orDie,
-            Effect.map((row) => synchronized.push(row !== undefined)),
-            Effect.asVoid,
-          ),
-      )
-
-      yield* events.publish(SyncMessage, { id: EventV2.ID.create(), text: "durable" })
-
-      expect(synchronized).toEqual([true])
-    }),
-  )
-
-  it.effect("inserts sync event rows on publish", () =>
+  it.effect("inserts durable event rows on publish", () =>
     Effect.gen(function* () {
       const events = yield* EventV2.Service
       const { db } = yield* Database.Service
@@ -398,7 +355,7 @@ describe("EventV2", () => {
     }),
   )
 
-  it.effect("increments sync event seq per aggregate", () =>
+  it.effect("increments durable event seq per aggregate", () =>
     Effect.gen(function* () {
       const events = yield* EventV2.Service
       const { db } = yield* Database.Service
@@ -417,22 +374,22 @@ describe("EventV2", () => {
     }),
   )
 
-  it.effect("replays durable aggregate events after a cursor and tails new events", () =>
+  it.effect("replays durable aggregate events after a sequence and tails new events", () =>
     Effect.gen(function* () {
       const events = yield* EventV2.Service
       const aggregateID = EventV2.ID.create()
       yield* events.publish(SyncMessage, { id: aggregateID, text: "zero" })
       yield* events.publish(SyncMessage, { id: aggregateID, text: "one" })
       const fiber = yield* events
-        .aggregateEvents({ aggregateID, after: EventV2.Cursor.make(0) })
+        .durable({ aggregateID, after: 0 })
         .pipe(Stream.take(2), Stream.runCollect, Effect.forkScoped)
       yield* Effect.yieldNow
 
       yield* events.publish(SyncMessage, { id: aggregateID, text: "two" })
 
-      expect(Array.from(yield* Fiber.join(fiber)).map((event) => [event.cursor, event.event.data])).toEqual([
-        [EventV2.Cursor.make(1), { id: aggregateID, text: "one" }],
-        [EventV2.Cursor.make(2), { id: aggregateID, text: "two" }],
+      expect(Array.from(yield* Fiber.join(fiber)).map((event) => [event.durable?.seq, event.data])).toEqual([
+        [1, { id: aggregateID, text: "one" }],
+        [2, { id: aggregateID, text: "two" }],
       ])
     }),
   )
@@ -442,20 +399,18 @@ describe("EventV2", () => {
       const events = yield* EventV2.Service
       const aggregateID = EventV2.ID.create()
       yield* events.publish(SyncMessage, { id: aggregateID, text: "zero" })
-      const fiber = yield* events
-        .aggregateEvents({ aggregateID })
-        .pipe(Stream.take(2), Stream.runCollect, Effect.forkScoped)
+      const fiber = yield* events.durable({ aggregateID }).pipe(Stream.take(2), Stream.runCollect, Effect.forkScoped)
 
       yield* events.publish(SyncMessage, { id: aggregateID, text: "one" })
 
       expect(
         Array.from(yield* Fiber.join(fiber)).map((event) => [
-          event.cursor,
-          (event.event.data as { text: string }).text,
+          event.durable?.seq,
+          (event.data as { text: string }).text,
         ]),
       ).toEqual([
-        [EventV2.Cursor.make(0), "zero"],
-        [EventV2.Cursor.make(1), "one"],
+        [0, "zero"],
+        [1, "one"],
       ])
     }),
   )
@@ -465,30 +420,27 @@ describe("EventV2", () => {
       const readStarted = yield* Deferred.make<void>()
       const continueRead = yield* Deferred.make<void>()
       let pause = true
-      const database = Database.layerFromPath(":memory:")
       const eventLayer = EventV2.layerWith({
         beforeAggregateRead: () =>
           pause
             ? Deferred.succeed(readStarted, undefined).pipe(Effect.andThen(Deferred.await(continueRead)))
             : Effect.void,
-      }).pipe(Layer.provide(database))
+      }).pipe(Layer.provide(Database.defaultLayer))
 
       yield* Effect.gen(function* () {
         const events = yield* EventV2.Service
         const aggregateID = EventV2.ID.create()
-        const fiber = yield* events
-          .aggregateEvents({ aggregateID })
-          .pipe(Stream.take(1), Stream.runCollect, Effect.forkScoped)
+        const fiber = yield* events.durable({ aggregateID }).pipe(Stream.take(1), Stream.runCollect, Effect.forkScoped)
         yield* Deferred.await(readStarted)
 
         pause = false
         yield* events.publish(SyncMessage, { id: aggregateID, text: "during handoff" })
         yield* Deferred.succeed(continueRead, undefined)
 
-        expect(Array.from(yield* Fiber.join(fiber)).map((event) => [event.cursor, event.event.data])).toEqual([
-          [EventV2.Cursor.make(0), { id: aggregateID, text: "during handoff" }],
+        expect(Array.from(yield* Fiber.join(fiber)).map((event) => [event.durable?.seq, event.data])).toEqual([
+          [0, { id: aggregateID, text: "during handoff" }],
         ])
-      }).pipe(Effect.provide(Layer.mergeAll(database, eventLayer)))
+      }).pipe(Effect.provide(Layer.mergeAll(Database.defaultLayer, eventLayer)))
     }),
   )
 
@@ -498,7 +450,7 @@ describe("EventV2", () => {
       const aggregateID = EventV2.ID.create()
       const count = 64
       const fiber = yield* events
-        .aggregateEvents({ aggregateID })
+        .durable({ aggregateID })
         .pipe(Stream.take(count), Stream.runCollect, Effect.forkScoped)
       yield* Effect.yieldNow
 
@@ -506,11 +458,8 @@ describe("EventV2", () => {
         yield* events.publish(SyncMessage, { id: aggregateID, text: String(index) })
       }
 
-      expect(Array.from(yield* Fiber.join(fiber)).map((event) => [event.cursor, event.event.data])).toEqual(
-        Array.from({ length: count }, (_, index) => [
-          EventV2.Cursor.make(index),
-          { id: aggregateID, text: String(index) },
-        ]),
+      expect(Array.from(yield* Fiber.join(fiber)).map((event) => [event.durable?.seq, event.data])).toEqual(
+        Array.from({ length: count }, (_, index) => [index, { id: aggregateID, text: String(index) }]),
       )
     }),
   )
@@ -519,15 +468,13 @@ describe("EventV2", () => {
     Effect.gen(function* () {
       const events = yield* EventV2.Service
       const aggregateID = EventV2.ID.create()
-      const fiber = yield* events
-        .aggregateEvents({ aggregateID })
-        .pipe(Stream.take(1), Stream.runCollect, Effect.forkScoped)
+      const fiber = yield* events.durable({ aggregateID }).pipe(Stream.take(1), Stream.runCollect, Effect.forkScoped)
       yield* Effect.yieldNow
 
       yield* events.publish(Message, { text: "live only" })
       yield* events.publish(SyncMessage, { id: aggregateID, text: "durable" })
 
-      expect(Array.from(yield* Fiber.join(fiber)).map((event) => event.event.type)).toEqual([SyncMessage.type])
+      expect(Array.from(yield* Fiber.join(fiber)).map((event) => event.type)).toEqual([SyncMessage.type])
     }),
   )
 
@@ -550,7 +497,7 @@ describe("EventV2", () => {
     }),
   )
 
-  it.effect("replays sync events through projectors", () =>
+  it.effect("replays durable events through projectors", () =>
     Effect.gen(function* () {
       const events = yield* EventV2.Service
       const received = new Array<EventV2.Payload>()
@@ -706,7 +653,7 @@ describe("EventV2", () => {
         })
         .pipe(Effect.exit)
 
-      expect(String(exit)).toContain("Unknown sync event type")
+      expect(String(exit)).toContain("Unknown durable event type")
     }),
   )
 
@@ -843,7 +790,7 @@ describe("EventV2", () => {
       const replayed = {
         id: published.id,
         type: EventV2.versionedType(SyncMessage.type, 1),
-        seq: published.seq!,
+        seq: published.durable!.seq,
         aggregateID,
         data: published.data,
       }
@@ -988,7 +935,7 @@ describe("EventV2", () => {
       yield* events.replay(replayed, { publish: true })
       yield* events.replay(replayed, { publish: true })
 
-      expect(received).toMatchObject([{ id: replayed.id, seq: 0, data: replayed.data }])
+      expect(received).toMatchObject([{ id: replayed.id, durable: { seq: 0, version: 1 }, data: replayed.data }])
     }),
   )
 
@@ -1110,7 +1057,7 @@ describe("EventV2", () => {
     }),
   )
 
-  it.effect("remove clears sync event sequence", () =>
+  it.effect("remove clears durable event sequence", () =>
     Effect.gen(function* () {
       const events = yield* EventV2.Service
       const received = new Array<EventV2.Payload>()

packages/core/test/filesystem/filesystem.test.ts

@@ -5,7 +5,7 @@ import { FSUtil } from "@opencode-ai/core/fs-util"
 import { testEffect } from "../lib/effect"
 import path from "path"
 
-const live = FSUtil.layer.pipe(Layer.provideMerge(NodeFileSystem.layer))
+const live = Layer.merge(FSUtil.defaultLayer, NodeFileSystem.layer)
 const { effect: it } = testEffect(live)
 
 describe("FSUtil", () => {

packages/core/test/filesystem/search.test.ts

@@ -22,7 +22,7 @@ describe("Ripgrep", () => {
         yield* Effect.promise(() => fs.mkdir(path.join(cwd, "src")))
         yield* Effect.promise(() => fs.writeFile(path.join(cwd, "src", "match.ts"), "needle\n"))
         const result = yield* (yield* Ripgrep.Service).glob({ cwd, pattern: "**/*.ts", limit: 10 })
-        expect(result.map((item) => item.path)).toEqual([RelativePath.make(path.join("src", "match.ts"))])
+        expect(result.map((item) => item.path)).toEqual([RelativePath.make("src/match.ts")])
       }),
     ),
   )
@@ -35,7 +35,7 @@ describe("Ripgrep", () => {
         yield* Effect.promise(() => fs.writeFile(path.join(cwd, "src", "skip.txt"), "needle\n"))
         const result = yield* (yield* Ripgrep.Service).grep({ cwd, pattern: "needle", include: "*.ts", limit: 10 })
         expect(result).toHaveLength(1)
-        expect(result[0]?.entry.path).toBe(RelativePath.make(path.join("src", "match.ts")))
+        expect(result[0]?.entry.path).toBe(RelativePath.make("src/match.ts"))
         expect(result[0]?.submatches[0]?.text).toBe("needle")
       }),
     ),

packages/core/test/fixture/location.ts

@@ -1,6 +1,8 @@
 import { Location } from "@opencode-ai/core/location"
 import { Project } from "@opencode-ai/core/project"
 import { AbsolutePath } from "@opencode-ai/core/schema"
+import { Effect, Layer } from "effect"
+import { tmpdir } from "./tmpdir"
 
 export function location(ref: Location.Ref, input: { projectDirectory?: AbsolutePath; vcs?: Project.Vcs } = {}) {
   return {
@@ -10,3 +12,15 @@ export function location(ref: Location.Ref, input: { projectDirectory?: Absolute
     vcs: input.vcs,
   } satisfies Location.Interface
 }
+
+export const tempLocationLayer = Layer.unwrap(
+  Effect.acquireRelease(
+    Effect.promise(() => tmpdir()),
+    (tmp) => Effect.promise(() => tmp[Symbol.asyncDispose]()),
+  ).pipe(
+    Effect.map((tmp) => {
+      const ref = Location.Ref.make({ directory: AbsolutePath.make(tmp.path) })
+      return Layer.succeed(Location.Service, Location.Service.of(location(ref)))
+    }),
+  ),
+)

packages/core/test/integration.test.ts

@@ -4,45 +4,12 @@ import * as TestClock from "effect/testing/TestClock"
 import { Integration } from "@opencode-ai/core/integration"
 import { Credential } from "@opencode-ai/core/credential"
 import { EventV2 } from "@opencode-ai/core/event"
-import { it } from "./lib/effect"
+import { testEffect } from "./lib/effect"
 
-const layer = Integration.locationLayer.pipe(
-  Layer.provide(EventV2.defaultLayer),
-  Layer.provide(
-    Layer.mock(Credential.Service)({
-      create: () => Effect.die("unexpected credential creation"),
-      list: () => Effect.succeed([]),
-    }),
-  ),
+const it = testEffect(
+  Integration.locationLayer.pipe(Layer.provideMerge(Credential.defaultLayer), Layer.provideMerge(EventV2.defaultLayer)),
 )
 
-function connectionLayer(
-  created: Array<{
-    integrationID: Integration.ID
-    label?: string
-    value: Credential.Info
-  }>,
-) {
-  return Integration.locationLayer.pipe(
-    Layer.provideMerge(EventV2.defaultLayer),
-    Layer.provide(
-      Layer.mock(Credential.Service)({
-        create: (input) =>
-          Effect.sync(() => {
-            created.push(input)
-            return new Credential.Stored({
-              id: Credential.ID.create(),
-              integrationID: input.integrationID,
-              label: input.label ?? "default",
-              value: input.value,
-            })
-          }),
-        list: () => Effect.succeed([]),
-      }),
-    ),
-  )
-}
-
 describe("Integration", () => {
   it.effect("registers integrations through the editor", () =>
     Effect.gen(function* () {
@@ -59,7 +26,7 @@ describe("Integration", () => {
 
       yield* Scope.close(scope, Exit.void)
       expect(yield* integrations.get(openai)).toBeUndefined()
-    }).pipe(Effect.provide(layer)),
+    }),
   )
 
   it.effect("reveals the previous registration when an override closes", () =>
@@ -80,7 +47,7 @@ describe("Integration", () => {
       yield* Scope.close(second, Exit.void)
       expect((yield* integrations.get(id))?.name).toBe("OpenAI")
       expect((yield* integrations.list()).map((integration) => integration.id)).toEqual([id])
-    }).pipe(Effect.provide(layer)),
+    }),
   )
 
   it.effect("registers and overrides methods independently", () =>
@@ -128,17 +95,13 @@ describe("Integration", () => {
       yield* Scope.close(second, Exit.void)
       expect((yield* integrations.get(integrationID))?.methods[0]).toMatchObject({ label: "ChatGPT" })
       expect((yield* integrations.get(integrationID))?.methods).toEqual([expect.objectContaining({ id: methodID })])
-    }).pipe(Effect.provide(layer)),
+    }),
   )
 
-  it.effect("connects with a key and stores the credential", () => {
-    const created: Array<{
-      integrationID: Integration.ID
-      label?: string
-      value: Credential.Info
-    }> = []
-    return Effect.gen(function* () {
+  it.effect("connects with a key and stores the credential", () =>
+    Effect.gen(function* () {
       const integrations = yield* Integration.Service
+      const credentials = yield* Credential.Service
       const events = yield* EventV2.Service
       const integrationID = Integration.ID.make("openai")
       yield* integrations.transform((editor) =>
@@ -158,25 +121,21 @@ describe("Integration", () => {
         label: "Work",
       })
 
-      expect(created).toEqual([
-        {
+      expect(yield* credentials.list(integrationID)).toEqual([
+        expect.objectContaining({
           integrationID,
           label: "Work",
           value: new Credential.Key({ type: "key", key: "secret" }),
-        },
+        }),
       ])
       expect((yield* Fiber.join(updated)).length).toBe(1)
-    }).pipe(Effect.provide(connectionLayer(created)))
-  })
+    }),
+  )
 
-  it.effect("completes code OAuth once and stores the credential", () => {
-    const created: Array<{
-      integrationID: Integration.ID
-      label?: string
-      value: Credential.Info
-    }> = []
-    return Effect.gen(function* () {
+  it.effect("completes code OAuth once and stores the credential", () =>
+    Effect.gen(function* () {
       const integrations = yield* Integration.Service
+      const credentials = yield* Credential.Service
       const integrationID = Integration.ID.make("openai")
       const methodID = Integration.MethodID.make("chatgpt")
       yield* integrations.transform((editor) =>
@@ -212,29 +171,27 @@ describe("Integration", () => {
       expect(attempt.mode).toBe("code")
       yield* integrations.attempt.complete({ attemptID: attempt.attemptID, code: "1234" })
 
-      expect(created[0]).toEqual({
-        integrationID,
-        label: "Personal",
-        value: new Credential.OAuth({
-          type: "oauth",
-          methodID,
-          access: "access",
-          refresh: "refresh",
-          expires: 1,
-          metadata: { code: "1234" },
+      expect((yield* credentials.list(integrationID))[0]).toEqual(
+        expect.objectContaining({
+          integrationID,
+          label: "Personal",
+          value: new Credential.OAuth({
+            type: "oauth",
+            methodID,
+            access: "access",
+            refresh: "refresh",
+            expires: 1,
+            metadata: { code: "1234" },
+          }),
         }),
-      })
-    }).pipe(Effect.provide(connectionLayer(created)))
-  })
+      )
+    }),
+  )
 
-  it.effect("keeps code attempts open when the code is missing and closes them on cancel", () => {
-    const created: Array<{
-      integrationID: Integration.ID
-      label?: string
-      value: Credential.Info
-    }> = []
-    return Effect.gen(function* () {
+  it.effect("keeps code attempts open when the code is missing and closes them on cancel", () =>
+    Effect.gen(function* () {
       const integrations = yield* Integration.Service
+      const credentials = yield* Credential.Service
       const integrationID = Integration.ID.make("openai")
       const methodID = Integration.MethodID.make("chatgpt")
       let closed = false
@@ -261,18 +218,14 @@ describe("Integration", () => {
       expect(closed).toBe(false)
       yield* integrations.attempt.cancel(attempt.attemptID)
       expect(closed).toBe(true)
-      expect(created).toEqual([])
-    }).pipe(Effect.provide(connectionLayer(created)))
-  })
+      expect(yield* credentials.list(integrationID)).toEqual([])
+    }),
+  )
 
-  it.effect("completes auto OAuth in the background", () => {
-    const created: Array<{
-      integrationID: Integration.ID
-      label?: string
-      value: Credential.Info
-    }> = []
-    return Effect.gen(function* () {
+  it.effect("completes auto OAuth in the background", () =>
+    Effect.gen(function* () {
       const integrations = yield* Integration.Service
+      const credentials = yield* Credential.Service
       const integrationID = Integration.ID.make("openai")
       const methodID = Integration.MethodID.make("browser")
       yield* integrations.transform((editor) =>
@@ -297,18 +250,14 @@ describe("Integration", () => {
         status: "complete",
         time: attempt.time,
       })
-      expect(created).toHaveLength(1)
-    }).pipe(Effect.provide(connectionLayer(created)))
-  })
+      expect(yield* credentials.list(integrationID)).toHaveLength(1)
+    }),
+  )
 
-  it.effect("expires abandoned OAuth attempts", () => {
-    const created: Array<{
-      integrationID: Integration.ID
-      label?: string
-      value: Credential.Info
-    }> = []
-    return Effect.gen(function* () {
+  it.effect("expires abandoned OAuth attempts", () =>
+    Effect.gen(function* () {
       const integrations = yield* Integration.Service
+      const credentials = yield* Credential.Service
       const integrationID = Integration.ID.make("openai")
       const methodID = Integration.MethodID.make("browser")
       let closed = false
@@ -337,34 +286,12 @@ describe("Integration", () => {
         time: attempt.time,
       })
       expect(closed).toBe(true)
-      expect(created).toEqual([])
-    }).pipe(Effect.provide(connectionLayer(created)))
-  })
+      expect(yield* credentials.list(integrationID)).toEqual([])
+    }),
+  )
 
   it.effect("projects credential and env connections", () => {
     const integrationID = Integration.ID.make("acme")
-    const rows = [
-      {
-        id: Credential.ID.create(),
-        integrationID,
-        label: "Work",
-        value: new Credential.Key({ type: "key", key: "a" }),
-      },
-      {
-        id: Credential.ID.create(),
-        integrationID,
-        label: "Personal",
-        value: new Credential.Key({ type: "key", key: "b" }),
-      },
-    ]
-    const projectionLayer = Integration.locationLayer.pipe(
-      Layer.provide(EventV2.defaultLayer),
-      Layer.provide(
-        Layer.mock(Credential.Service)({
-          list: () => Effect.succeed(rows.map((row) => new Credential.Stored(row))),
-        }),
-      ),
-    )
     return Effect.acquireUseRelease(
       Effect.sync(() => {
         const previous = process.env.INTEGRATION_TEST_ACME_KEY
@@ -375,6 +302,7 @@ describe("Integration", () => {
       () =>
         Effect.gen(function* () {
           const integrations = yield* Integration.Service
+          const credentials = yield* Credential.Service
           yield* integrations.transform((editor) =>
             editor.method.update({
               integrationID,
@@ -384,23 +312,33 @@ describe("Integration", () => {
               },
             }),
           )
+          const work = yield* credentials.create({
+            integrationID,
+            label: "Work",
+            value: new Credential.Key({ type: "key", key: "a" }),
+          })
+          const personal = yield* credentials.create({
+            integrationID,
+            label: "Personal",
+            value: new Credential.Key({ type: "key", key: "b" }),
+          })
 
           // Stored credentials and detected env vars appear as connections.
           expect((yield* integrations.get(integrationID))?.connections).toEqual([
-            { type: "credential", id: rows[0]!.id, label: "Work" },
             {
               type: "credential",
-              id: rows[1]!.id,
+              id: personal.id,
               label: "Personal",
             },
             { type: "env", name: "INTEGRATION_TEST_ACME_KEY" },
           ])
           expect(yield* integrations.connection.forIntegration(integrationID)).toEqual({
             type: "credential",
-            id: rows[1]!.id,
+            id: personal.id,
             label: "Personal",
           })
-        }).pipe(Effect.provide(projectionLayer)),
+          expect(work.id).not.toBe(personal.id)
+        }),
       (previous) =>
         Effect.sync(() => {
           if (previous === undefined) delete process.env.INTEGRATION_TEST_ACME_KEY

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

@@ -1,16 +1,20 @@
 import fs from "fs/promises"
 import path from "path"
 import { describe, expect } from "bun:test"
-import { Deferred, Effect, Equal, Hash, Layer, Schema, Stream } from "effect"
+import { DateTime, Deferred, Effect, Equal, Hash, Layer, Schema, Stream } from "effect"
 import { Tool } from "@opencode-ai/core/public"
 import { define } from "@opencode-ai/plugin/v2/effect"
 import { AgentV2 } from "@opencode-ai/core/agent"
 import { Catalog } from "@opencode-ai/core/catalog"
 import { LocationServiceMap } from "@opencode-ai/core/location-layer"
 import { Location } from "@opencode-ai/core/location"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginBoot } from "@opencode-ai/core/plugin/boot"
+import { ProjectV2 } from "@opencode-ai/core/project"
 import { ProviderV2 } from "@opencode-ai/core/provider"
 import { AbsolutePath } from "@opencode-ai/core/schema"
+import { SessionV2 } from "@opencode-ai/core/session"
+import { SessionRunnerModel } from "@opencode-ai/core/session/runner/model"
 import { tmpdir } from "./fixture/tmpdir"
 import { testEffect } from "./lib/effect"
 import { toolDefinitions } from "./lib/tool"
@@ -36,8 +40,7 @@ const it = testEffect(
         Layer.mergeAll(
           Project.defaultLayer,
           EventV2.defaultLayer,
-          Credential.defaultLayer,
-          Credential.layer.pipe(Layer.provide(Database.layerFromPath(":memory:").pipe(Layer.fresh))),
+          Credential.defaultLayer.pipe(Layer.fresh),
           Npm.defaultLayer,
           ModelsDev.defaultLayer,
           FSUtil.defaultLayer,
@@ -137,6 +140,56 @@ describe("LocationServiceMap", () => {
     ),
   )
 
+  it.live("rejects an unavailable selected model during location model resolution", () =>
+    Effect.acquireRelease(
+      Effect.promise(() => tmpdir()),
+      (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
+    ).pipe(
+      Effect.flatMap((dir) =>
+        Effect.gen(function* () {
+          const location = Location.Ref.make({ directory: AbsolutePath.make(dir.path) })
+          yield* Effect.promise(() =>
+            fs.writeFile(
+              path.join(dir.path, "opencode.json"),
+              JSON.stringify({
+                providers: {
+                  unavailable: {
+                    name: "Unavailable",
+                    api: { type: "native", settings: {} },
+                    models: { chat: { disabled: true } },
+                  },
+                },
+              }),
+            ),
+          )
+          const failure = yield* SessionRunnerModel.Service.use((models) =>
+            models.resolve(
+              SessionV2.Info.make({
+                id: SessionV2.ID.make("ses_unavailable_model"),
+                projectID: ProjectV2.ID.global,
+                title: "test",
+                model: {
+                  id: ModelV2.ID.make("chat"),
+                  providerID: ProviderV2.ID.make("unavailable"),
+                },
+                cost: 0,
+                tokens: { input: 0, output: 0, reasoning: 0, cache: { read: 0, write: 0 } },
+                time: { created: DateTime.makeUnsafe(0), updated: DateTime.makeUnsafe(0) },
+                location,
+              }),
+            ),
+          ).pipe(Effect.provide(LocationServiceMap.get(location)), Effect.flip)
+
+          expect(failure).toMatchObject({
+            _tag: "SessionRunnerModel.ModelUnavailableError",
+            providerID: "unavailable",
+            modelID: "chat",
+          })
+        }),
+      ),
+    ),
+  )
+
   it.live("installs public plugins into a location", () =>
     Effect.acquireRelease(
       Effect.promise(() => tmpdir()),

packages/core/test/model.test.ts

@@ -21,3 +21,11 @@ describe("ModelV2.Ref", () => {
     })
   })
 })
+
+describe("ModelV2.Info", () => {
+  test("creates an empty model without modalities", () => {
+    const model = ModelV2.Info.empty(ProviderV2.ID.make("custom"), ModelV2.ID.make("model"))
+
+    expect(model.capabilities).toEqual({ tools: false, input: [], output: [] })
+  })
+})

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

@@ -21,34 +21,39 @@ import { SessionStore } from "@opencode-ai/core/session/store"
 import { tmpdir } from "./fixture/tmpdir"
 import { testEffect } from "./lib/effect"
 
-const database = Database.layerFromPath(":memory:")
-const events = EventV2.layer.pipe(Layer.provide(database))
-const directories = ProjectDirectories.layer.pipe(Layer.provide(database), Layer.provide(events))
-const projector = SessionProjector.layer.pipe(Layer.provide(database), Layer.provide(events))
 const project = Project.layer.pipe(
-  Layer.provide(database),
+  Layer.provide(Database.defaultLayer),
   Layer.provide(FSUtil.defaultLayer),
   Layer.provide(Git.defaultLayer),
-  Layer.provide(directories),
+  Layer.provide(ProjectDirectories.defaultLayer),
 )
-const store = SessionStore.layer.pipe(Layer.provide(database))
 const sessions = SessionV2.layer.pipe(
-  Layer.provide(database),
-  Layer.provide(events),
+  Layer.provide(Database.defaultLayer),
+  Layer.provide(EventV2.defaultLayer),
   Layer.provide(project),
-  Layer.provide(store),
+  Layer.provide(SessionStore.defaultLayer),
   Layer.provide(SessionExecution.noopLayer),
 )
 const layer = MoveSession.layer.pipe(
-  Layer.provide(database),
+  Layer.provide(Database.defaultLayer),
   Layer.provide(FSUtil.defaultLayer),
   Layer.provide(Git.defaultLayer),
-  Layer.provide(events),
+  Layer.provide(EventV2.defaultLayer),
   Layer.provide(project),
   Layer.provide(sessions),
 )
 const it = testEffect(
-  Layer.mergeAll(layer, database, events, directories, project, projector, store, SessionExecution.noopLayer, sessions),
+  Layer.mergeAll(
+    layer,
+    Database.defaultLayer,
+    EventV2.defaultLayer,
+    ProjectDirectories.defaultLayer,
+    project,
+    SessionProjector.defaultLayer,
+    SessionStore.defaultLayer,
+    SessionExecution.noopLayer,
+    sessions,
+  ),
 )
 
 function abs(input: string) {

packages/core/test/permission.test.ts

@@ -18,29 +18,25 @@ import { eq } from "drizzle-orm"
 import { location } from "./fixture/location"
 import { testEffect } from "./lib/effect"
 
-const database = Database.layerFromPath(":memory:")
 const current = Layer.succeed(
   Location.Service,
   Location.Service.of(location({ directory: AbsolutePath.make("/project") })),
 )
-const events = EventV2.layer.pipe(Layer.provide(database))
-const store = SessionStore.layer.pipe(Layer.provide(database))
 const sessions = SessionV2.layer.pipe(
-  Layer.provide(events),
-  Layer.provide(database),
-  Layer.provide(store),
+  Layer.provide(EventV2.defaultLayer),
+  Layer.provide(Database.defaultLayer),
+  Layer.provide(SessionStore.defaultLayer),
   Layer.provide(Project.defaultLayer),
   Layer.provide(SessionExecution.noopLayer),
 )
-const saved = PermissionSaved.layer.pipe(Layer.provide(database))
 const layer = PermissionV2.locationLayer.pipe(
-  Layer.provideMerge(database),
-  Layer.provideMerge(store),
-  Layer.provideMerge(events),
+  Layer.provideMerge(Database.defaultLayer),
+  Layer.provideMerge(SessionStore.defaultLayer),
+  Layer.provideMerge(EventV2.defaultLayer),
   Layer.provideMerge(current),
   Layer.provideMerge(sessions),
   Layer.provideMerge(SessionExecution.noopLayer),
-  Layer.provideMerge(saved),
+  Layer.provideMerge(PermissionSaved.defaultLayer),
 )
 const it = testEffect(layer)
 

packages/core/test/plugin.test.ts

@@ -46,6 +46,40 @@ describe("PluginV2", () => {
     }),
   )
 
+  it.effect("batches plugin state rebuilds when the registry layer finalizes", () =>
+    Effect.gen(function* () {
+      let finalized = 0
+      const values = State.create({
+        initial: () => ({ values: [] as string[] }),
+        draft: (draft) => ({ add: (value: string) => draft.values.push(value) }),
+        finalize: () => Effect.sync(() => finalized++),
+      })
+      const layerScope = yield* Scope.fork(yield* Scope.Scope)
+      const plugin = Context.get(yield* Layer.buildWithScope(Layer.fresh(plugins), layerScope), PluginV2.Service)
+
+      yield* State.batch(
+        Effect.forEach(
+          ["first", "second"],
+          (id) =>
+            plugin.add({
+              id: PluginV2.ID.make(id),
+              effect: values
+                .transform((editor) => {
+                  editor.add(id)
+                })
+                .pipe(Effect.asVoid),
+            }),
+          { discard: true },
+        ),
+      )
+      finalized = 0
+
+      yield* Scope.close(layerScope, Exit.void)
+      expect(values.get().values).toEqual([])
+      expect(finalized).toBe(1)
+    }),
+  )
+
   it.effect("serializes same-ID additions and leaves one removable attachment", () =>
     Effect.gen(function* () {
       const values = state()

packages/core/test/plugin/fixture.ts

@@ -0,0 +1,48 @@
+import { AgentV2 } from "@opencode-ai/core/agent"
+import { Catalog } from "@opencode-ai/core/catalog"
+import { CommandV2 } from "@opencode-ai/core/command"
+import { Credential } from "@opencode-ai/core/credential"
+import { EventV2 } from "@opencode-ai/core/event"
+import { FileSystem } from "@opencode-ai/core/filesystem"
+import { FSUtil } from "@opencode-ai/core/fs-util"
+import { Global } from "@opencode-ai/core/global"
+import { Npm } from "@opencode-ai/core/npm"
+import { PluginV2 } from "@opencode-ai/core/plugin"
+import { Reference } from "@opencode-ai/core/reference"
+import { RepositoryCache } from "@opencode-ai/core/repository-cache"
+import { Ripgrep } from "@opencode-ai/core/ripgrep"
+import { SkillV2 } from "@opencode-ai/core/skill"
+import { SkillDiscovery } from "@opencode-ai/core/skill/discovery"
+import { Effect, Layer } from "effect"
+import { tempLocationLayer } from "../fixture/location"
+
+export const PluginTestLayer = Layer.mergeAll(
+  AgentV2.locationLayer,
+  CommandV2.locationLayer,
+  Catalog.locationLayer,
+  FileSystem.locationLayer,
+  PluginV2.locationLayer,
+  Reference.locationLayer,
+  SkillV2.locationLayer,
+).pipe(
+  Layer.provideMerge(
+    Layer.mergeAll(
+      Credential.defaultLayer,
+      EventV2.defaultLayer,
+      FSUtil.defaultLayer,
+      Global.defaultLayer,
+      Layer.succeed(
+        Npm.Service,
+        Npm.Service.of({
+          add: () => Effect.succeed({ directory: "", entrypoint: undefined }),
+          install: () => Effect.void,
+          which: () => Effect.succeed(undefined),
+        }),
+      ),
+      RepositoryCache.defaultLayer,
+      SkillDiscovery.defaultLayer,
+      Ripgrep.defaultLayer,
+      tempLocationLayer,
+    ),
+  ),
+)

packages/core/test/plugin/host.ts

@@ -255,7 +255,9 @@ function method(value: Integration.Method) {
   }
 }
 
-function internalMethod(value: IntegrationOAuthMethod | IntegrationKeyMethod | IntegrationEnvMethod): Integration.Method {
+function internalMethod(
+  value: IntegrationOAuthMethod | IntegrationKeyMethod | IntegrationEnvMethod,
+): Integration.Method {
   if (value.type === "env") return value
   if (value.type === "key") return value
   return {

packages/core/test/plugin/models-dev.test.ts

@@ -24,11 +24,7 @@ const locationLayer = Layer.succeed(
 )
 const plugins = PluginV2.layer.pipe(Layer.provide(events))
 const policy = Policy.layer.pipe(Layer.provide(locationLayer))
-const connections = Credential.layer.pipe(
-  Layer.fresh,
-  Layer.provide(Database.layerFromPath(":memory:").pipe(Layer.fresh)),
-  Layer.provide(events),
-)
+const connections = Credential.defaultLayer.pipe(Layer.fresh)
 const integrations = Integration.locationLayer.pipe(Layer.provide(events), Layer.provide(connections))
 const catalog = Catalog.layer.pipe(
   Layer.provide(Layer.mergeAll(events, locationLayer, plugins, policy, connections, integrations)),

packages/core/test/plugin/provider-alibaba.test.ts

@@ -3,17 +3,35 @@ import { createAlibaba } from "@ai-sdk/alibaba"
 import { Effect } from "effect"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { AlibabaPlugin } from "@opencode-ai/core/plugin/provider/alibaba"
-import { addPlugin, it, model } from "./provider-helper"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: AlibabaPlugin.id, effect: AlibabaPlugin.effect(host) })
+})
 
 describe("AlibabaPlugin", () => {
   it.effect("creates an Alibaba SDK for @ai-sdk/alibaba", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, AlibabaPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("alibaba", "qwen"), package: "@ai-sdk/alibaba", options: { name: "alibaba" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("alibaba"), ModelV2.ID.make("qwen")),
+            api: { id: ModelV2.ID.make("qwen"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/alibaba",
+          options: { name: "alibaba" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -23,10 +41,17 @@ describe("AlibabaPlugin", () => {
   it.effect("ignores non-Alibaba SDK packages", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, AlibabaPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("alibaba", "qwen"), package: "@ai-sdk/openai-compatible", options: { name: "alibaba" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("alibaba"), ModelV2.ID.make("qwen")),
+            api: { id: ModelV2.ID.make("qwen"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/openai-compatible",
+          options: { name: "alibaba" },
+        },
         {},
       )
       expect(result.sdk).toBeUndefined()
@@ -36,11 +61,14 @@ describe("AlibabaPlugin", () => {
   it.effect("matches the old bundled Alibaba SDK provider naming", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, AlibabaPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-alibaba", "qwen"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-alibaba"), ModelV2.ID.make("qwen")),
+            api: { id: ModelV2.ID.make("qwen"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/alibaba",
           options: { name: "custom-alibaba", apiKey: "test" },
         },
@@ -56,8 +84,11 @@ describe("AlibabaPlugin", () => {
   it.effect("uses the old default languageModel(api.id) behavior", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, AlibabaPlugin)
-      const item = model("alibaba", "alias", { api: { id: ModelV2.ID.make("qwen-plus") } })
+      yield* addPlugin()
+      const item = new ModelV2.Info({
+        ...ModelV2.Info.empty(ProviderV2.ID.make("alibaba"), ModelV2.ID.make("alias")),
+        api: { id: ModelV2.ID.make("qwen-plus"), type: "aisdk", package: "test-provider" },
+      })
       const result = yield* plugin.trigger("aisdk.sdk", { model: item, package: "@ai-sdk/alibaba", options: {} }, {})
       const language = result.sdk?.languageModel(item.api.id)
       expect(language?.modelId).toBe("qwen-plus")

packages/core/test/plugin/provider-amazon-bedrock.test.ts

@@ -1,10 +1,61 @@
 import { describe, expect } from "bun:test"
+import type { LanguageModelV3 } from "@ai-sdk/provider"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { AmazonBedrockPlugin } from "@opencode-ai/core/plugin/provider/amazon-bedrock"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, fakeSelectorSdk, it, model, provider, required, withEnv } from "./provider-helper"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: AmazonBedrockPlugin.id, effect: AmazonBedrockPlugin.effect(host) })
+})
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, fx: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    fx,
+    (previous) =>
+      Effect.sync(() => {
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        })
+      }),
+  )
+}
+
+function fakeSelectorSdk(calls: string[]) {
+  const make = (method: string) => (id: string) => {
+    calls.push(`${method}:${id}`)
+    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+  return {
+    responses: make("responses"),
+    messages: make("messages"),
+    chat: make("chat"),
+    languageModel: make("languageModel"),
+  }
+}
 
 function bedrockBaseURL(sdk: unknown, modelID = "anthropic.claude-sonnet-4-5") {
   const language = (sdk as { languageModel: (id: string) => unknown }).languageModel(modelID)
@@ -28,11 +79,10 @@ function openAIUrl(language: unknown, path: string, modelId: string) {
 describe("AmazonBedrockPlugin", () => {
   it.effect("moves endpoint option to api URL", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, AmazonBedrockPlugin)
       yield* catalog.transform((catalog) => {
-        const bedrock = provider("amazon-bedrock", {
+        const bedrock = new ProviderV2.Info({
+          ...ProviderV2.Info.empty(ProviderV2.ID.amazonBedrock),
           api: { type: "aisdk", package: "@ai-sdk/amazon-bedrock" },
           request: {
             headers: {},
@@ -44,6 +94,7 @@ describe("AmazonBedrockPlugin", () => {
           item.request = bedrock.request
         })
       })
+      yield* addPlugin()
       const result = required(yield* catalog.provider.get(ProviderV2.ID.amazonBedrock))
       expect(result.api).toEqual({
         type: "aisdk",
@@ -58,11 +109,14 @@ describe("AmazonBedrockPlugin", () => {
     withEnv({ AWS_BEARER_TOKEN_BEDROCK: undefined, AWS_PROFILE: undefined, AWS_ACCESS_KEY_ID: undefined }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, AmazonBedrockPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+              api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/amazon-bedrock",
             options: {
               name: "amazon-bedrock",
@@ -83,11 +137,14 @@ describe("AmazonBedrockPlugin", () => {
     withEnv({ AWS_BEARER_TOKEN_BEDROCK: undefined, AWS_PROFILE: undefined, AWS_ACCESS_KEY_ID: undefined }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, AmazonBedrockPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+              api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/amazon-bedrock",
             options: {
               name: "amazon-bedrock",
@@ -117,11 +174,18 @@ describe("AmazonBedrockPlugin", () => {
       () =>
         Effect.gen(function* () {
           const plugin = yield* PluginV2.Service
-          yield* addPlugin(plugin, AmazonBedrockPlugin)
+          yield* addPlugin()
           const result = yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+                api: {
+                  id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"),
+                  type: "aisdk",
+                  package: "test-provider",
+                },
+              }),
               package: "@ai-sdk/amazon-bedrock",
               options: { name: "amazon-bedrock" },
             },
@@ -137,11 +201,14 @@ describe("AmazonBedrockPlugin", () => {
     withEnv({ AWS_BEARER_TOKEN_BEDROCK: "token", AWS_REGION: "us-east-1" }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, AmazonBedrockPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+              api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/amazon-bedrock",
             options: { name: "amazon-bedrock", region: "eu-west-1" },
           },
@@ -156,11 +223,14 @@ describe("AmazonBedrockPlugin", () => {
     withEnv({ AWS_BEARER_TOKEN_BEDROCK: "token", AWS_REGION: "eu-west-1" }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, AmazonBedrockPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+              api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/amazon-bedrock",
             options: { name: "amazon-bedrock" },
           },
@@ -175,11 +245,14 @@ describe("AmazonBedrockPlugin", () => {
     withEnv({ AWS_BEARER_TOKEN_BEDROCK: "token", AWS_REGION: undefined }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, AmazonBedrockPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+              api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/amazon-bedrock",
             options: { name: "amazon-bedrock" },
           },
@@ -195,11 +268,14 @@ describe("AmazonBedrockPlugin", () => {
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
         const headers: Array<string | null> = []
-        yield* addPlugin(plugin, AmazonBedrockPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+              api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/amazon-bedrock",
             options: {
               name: "amazon-bedrock",
@@ -224,11 +300,14 @@ describe("AmazonBedrockPlugin", () => {
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
         const headers: Array<string | null> = []
-        yield* addPlugin(plugin, AmazonBedrockPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+              api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/amazon-bedrock",
             options: {
               name: "amazon-bedrock",
@@ -252,12 +331,17 @@ describe("AmazonBedrockPlugin", () => {
     withEnv({ AWS_BEARER_TOKEN_BEDROCK: undefined, AWS_PROFILE: undefined, AWS_ACCESS_KEY_ID: undefined }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, AmazonBedrockPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("amazon-bedrock", "openai.gpt-5.5", {
-              api: { type: "aisdk", package: "@ai-sdk/amazon-bedrock/mantle" },
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("openai.gpt-5.5")),
+              api: {
+                id: ModelV2.ID.make("openai.gpt-5.5"),
+                type: "aisdk",
+                package: "@ai-sdk/amazon-bedrock/mantle",
+              },
             }),
             package: "@ai-sdk/amazon-bedrock/mantle",
             options: {
@@ -281,12 +365,17 @@ describe("AmazonBedrockPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, AmazonBedrockPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("amazon-bedrock", "openai.gpt-5.5", {
-            api: { type: "aisdk", package: "@ai-sdk/amazon-bedrock/mantle" },
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("openai.gpt-5.5")),
+            api: {
+              id: ModelV2.ID.make("openai.gpt-5.5"),
+              type: "aisdk",
+              package: "@ai-sdk/amazon-bedrock/mantle",
+            },
           }),
           sdk: fakeSelectorSdk(calls),
           options: { baseURL: "https://bedrock-mantle.us-east-2.api.aws/openai/v1", region: "us-east-2" },
@@ -296,8 +385,13 @@ describe("AmazonBedrockPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("amazon-bedrock", "openai.gpt-oss-safeguard-120b", {
-            api: { type: "aisdk", package: "@ai-sdk/amazon-bedrock/mantle" },
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("openai.gpt-oss-safeguard-120b")),
+            api: {
+              id: ModelV2.ID.make("openai.gpt-oss-safeguard-120b"),
+              type: "aisdk",
+              package: "@ai-sdk/amazon-bedrock/mantle",
+            },
           }),
           sdk: fakeSelectorSdk(calls),
           options: { region: "us-east-1" },
@@ -311,12 +405,17 @@ describe("AmazonBedrockPlugin", () => {
   it.effect("ignores other Bedrock provider subpaths", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, AmazonBedrockPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5", {
-            api: { type: "aisdk", package: "@ai-sdk/amazon-bedrock/anthropic" },
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+            api: {
+              id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"),
+              type: "aisdk",
+              package: "@ai-sdk/amazon-bedrock/anthropic",
+            },
           }),
           package: "@ai-sdk/amazon-bedrock/anthropic",
           options: { name: "amazon-bedrock" },
@@ -340,11 +439,18 @@ describe("AmazonBedrockPlugin", () => {
         Effect.gen(function* () {
           const plugin = yield* PluginV2.Service
           const headers: Array<string | null> = []
-          yield* addPlugin(plugin, AmazonBedrockPlugin)
+          yield* addPlugin()
           const result = yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+                api: {
+                  id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"),
+                  type: "aisdk",
+                  package: "test-provider",
+                },
+              }),
               package: "@ai-sdk/amazon-bedrock",
               options: {
                 name: "amazon-bedrock",
@@ -371,11 +477,14 @@ describe("AmazonBedrockPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, AmazonBedrockPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+            api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: {},
         },
@@ -384,7 +493,10 @@ describe("AmazonBedrockPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+            api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: { region: "eu-west-1" },
         },
@@ -393,7 +505,14 @@ describe("AmazonBedrockPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("amazon-bedrock", "global.anthropic.claude-sonnet-4-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("global.anthropic.claude-sonnet-4-5")),
+            api: {
+              id: ModelV2.ID.make("global.anthropic.claude-sonnet-4-5"),
+              type: "aisdk",
+              package: "test-provider",
+            },
+          }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: { region: "eu-west-1" },
         },
@@ -402,7 +521,10 @@ describe("AmazonBedrockPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+            api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: { region: "ap-northeast-1" },
         },
@@ -411,7 +533,10 @@ describe("AmazonBedrockPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+            api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: { region: "ap-southeast-2" },
         },
@@ -432,11 +557,14 @@ describe("AmazonBedrockPlugin", () => {
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
         const calls: string[] = []
-        yield* addPlugin(plugin, AmazonBedrockPlugin)
+        yield* addPlugin()
         yield* plugin.trigger(
           "aisdk.language",
           {
-            model: model("amazon-bedrock", "anthropic.claude-sonnet-4-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+              api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+            }),
             sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
             options: {},
           },
@@ -517,12 +645,15 @@ describe("AmazonBedrockPlugin", () => {
           expected: "au.anthropic.claude-sonnet-4-5",
         },
       ]
-      yield* addPlugin(plugin, AmazonBedrockPlugin)
+      yield* addPlugin()
       for (const item of cases) {
         yield* plugin.trigger(
           "aisdk.language",
           {
-            model: model("amazon-bedrock", item.modelID),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.amazonBedrock, ModelV2.ID.make(item.modelID)),
+              api: { id: ModelV2.ID.make(item.modelID), type: "aisdk", package: "test-provider" },
+            }),
             sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
             options: { region: item.region },
           },
@@ -537,11 +668,14 @@ describe("AmazonBedrockPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, AmazonBedrockPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("openai", "anthropic.claude-sonnet-4-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.openai, ModelV2.ID.make("anthropic.claude-sonnet-4-5")),
+            api: { id: ModelV2.ID.make("anthropic.claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: { region: "eu-west-1" },
         },

packages/core/test/plugin/provider-anthropic.test.ts

@@ -1,19 +1,34 @@
 import { describe, expect } from "bun:test"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { AnthropicPlugin } from "@opencode-ai/core/plugin/provider/anthropic"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, it, model, provider, required } from "./provider-helper"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: AnthropicPlugin.id, effect: AnthropicPlugin.effect(host) })
+})
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
 
 describe("AnthropicPlugin", () => {
   it.effect("applies legacy beta headers", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, AnthropicPlugin)
       yield* catalog.transform((catalog) => {
-        const item = provider("anthropic", {
+        const item = new ProviderV2.Info({
+          ...ProviderV2.Info.empty(ProviderV2.ID.anthropic),
           api: { type: "aisdk", package: "@ai-sdk/anthropic" },
           request: { headers: { Existing: "1" }, body: {} },
         })
@@ -22,6 +37,7 @@ describe("AnthropicPlugin", () => {
           draft.request = item.request
         })
       })
+      yield* addPlugin()
       expect(required(yield* catalog.provider.get(ProviderV2.ID.anthropic)).request.headers["anthropic-beta"]).toBe(
         "interleaved-thinking-2025-05-14,fine-grained-tool-streaming-2025-05-14",
       )
@@ -31,65 +47,52 @@ describe("AnthropicPlugin", () => {
 
   it.effect("ignores non-Anthropic providers", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, AnthropicPlugin)
-      yield* catalog.transform((catalog) => catalog.provider.update(provider("openai").id, () => {}))
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.openai)).request.headers["anthropic-beta"]).toBeUndefined()
+      yield* catalog.transform((catalog) => catalog.provider.update(ProviderV2.ID.openai, () => {}))
+      yield* addPlugin()
+      expect(
+        required(yield* catalog.provider.get(ProviderV2.ID.openai)).request.headers["anthropic-beta"],
+      ).toBeUndefined()
     }),
   )
 
   it.effect("creates Anthropic SDKs with the model provider ID as the SDK name", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      const providers: string[] = []
-      yield* addPlugin(plugin, AnthropicPlugin)
-      yield* plugin.add({
-        id: PluginV2.ID.make("anthropic-sdk-inspector"),
-        effect: Effect.succeed({
-          "aisdk.sdk": (evt) =>
-            Effect.sync(() => {
-              providers.push(evt.sdk.languageModel("claude-sonnet-4-5").provider)
-            }),
-        }),
-      })
-      yield* plugin.trigger(
+      yield* addPlugin()
+      const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-anthropic", "claude-sonnet-4-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-anthropic"), ModelV2.ID.make("claude-sonnet-4-5")),
+            api: { id: ModelV2.ID.make("claude-sonnet-4-5"), type: "aisdk", package: "@ai-sdk/anthropic" },
+          }),
           package: "@ai-sdk/anthropic",
           options: { name: "custom-anthropic", apiKey: "test" },
         },
         {},
       )
-      expect(providers).toEqual(["custom-anthropic"])
+      expect(result.sdk.languageModel("claude-sonnet-4-5").provider).toBe("custom-anthropic")
     }),
   )
 
   it.effect("uses the Anthropic provider ID as the SDK name for the bundled Anthropic provider", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      const providers: string[] = []
-      yield* addPlugin(plugin, AnthropicPlugin)
-      yield* plugin.add({
-        id: PluginV2.ID.make("anthropic-sdk-inspector"),
-        effect: Effect.succeed({
-          "aisdk.sdk": (evt) =>
-            Effect.sync(() => {
-              providers.push(evt.sdk.languageModel("claude-sonnet-4-5").provider)
-            }),
-        }),
-      })
-      yield* plugin.trigger(
+      yield* addPlugin()
+      const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("anthropic", "claude-sonnet-4-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.anthropic, ModelV2.ID.make("claude-sonnet-4-5")),
+            api: { id: ModelV2.ID.make("claude-sonnet-4-5"), type: "aisdk", package: "@ai-sdk/anthropic" },
+          }),
           package: "@ai-sdk/anthropic",
           options: { name: "anthropic", apiKey: "test" },
         },
         {},
       )
-      expect(providers).toEqual(["anthropic"])
+      expect(result.sdk.languageModel("claude-sonnet-4-5").provider).toBe("anthropic")
     }),
   )
 })

packages/core/test/plugin/provider-azure-cognitive-services.test.ts

@@ -1,23 +1,73 @@
 import { describe, expect } from "bun:test"
+import type { LanguageModelV3 } from "@ai-sdk/provider"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { AzureCognitiveServicesPlugin } from "@opencode-ai/core/plugin/provider/azure"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, fakeSelectorSdk, it, model, provider, required, withEnv } from "./provider-helper"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: AzureCognitiveServicesPlugin.id, effect: AzureCognitiveServicesPlugin.effect(host) })
+})
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, fx: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    fx,
+    (previous) =>
+      Effect.sync(() => {
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        })
+      }),
+  )
+}
+
+function fakeSelectorSdk(calls: string[]) {
+  const make = (method: string) => (id: string) => {
+    calls.push(`${method}:${id}`)
+    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+  return {
+    responses: make("responses"),
+    messages: make("messages"),
+    chat: make("chat"),
+    languageModel: make("languageModel"),
+  }
+}
 
 describe("AzureCognitiveServicesPlugin", () => {
   it.effect("maps the resource env var to the Azure SDK baseURL", () =>
     withEnv({ AZURE_COGNITIVE_SERVICES_RESOURCE_NAME: "cognitive" }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
-        yield* addPlugin(plugin, AzureCognitiveServicesPlugin)
         yield* catalog.transform((catalog) => {
           catalog.provider.update(ProviderV2.ID.make("azure-cognitive-services"), (item) => {
             item.api = { type: "aisdk", package: "@ai-sdk/openai-compatible" }
           })
         })
+        yield* addPlugin()
         const result = required(yield* catalog.provider.get(ProviderV2.ID.make("azure-cognitive-services")))
         expect(result.api).toEqual({
           type: "aisdk",
@@ -33,14 +83,16 @@ describe("AzureCognitiveServicesPlugin", () => {
   it.effect("leaves baseURL unset without resource env and ignores other providers", () =>
     withEnv({ AZURE_COGNITIVE_SERVICES_RESOURCE_NAME: undefined }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
-        yield* addPlugin(plugin, AzureCognitiveServicesPlugin)
         yield* catalog.transform((catalog) => {
-          const azure = provider("azure-cognitive-services", {
+          const azure = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.make("azure-cognitive-services")),
             api: { type: "aisdk", package: "@ai-sdk/openai-compatible" },
           })
-          const openai = provider("openai")
+          const openai = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.openai),
+            api: { type: "aisdk", package: "test-provider" },
+          })
           catalog.provider.update(azure.id, (item) => {
             item.api = azure.api
           })
@@ -48,6 +100,7 @@ describe("AzureCognitiveServicesPlugin", () => {
             item.api = openai.api
           })
         })
+        yield* addPlugin()
         const azure = required(yield* catalog.provider.get(ProviderV2.ID.make("azure-cognitive-services")))
         const openai = required(yield* catalog.provider.get(ProviderV2.ID.openai))
         expect(azure.request.body.baseURL).toBeUndefined()
@@ -62,11 +115,14 @@ describe("AzureCognitiveServicesPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, AzureCognitiveServicesPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("azure-cognitive-services", "deployment"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("azure-cognitive-services"), ModelV2.ID.make("deployment")),
+            api: { id: ModelV2.ID.make("deployment"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: fakeSelectorSdk(calls),
           options: { useCompletionUrls: true },
         },
@@ -80,15 +136,29 @@ describe("AzureCognitiveServicesPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, AzureCognitiveServicesPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
-        { model: model("azure-cognitive-services", "deployment"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("azure-cognitive-services"), ModelV2.ID.make("deployment")),
+            api: { id: ModelV2.ID.make("deployment"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       const ignored = yield* plugin.trigger(
         "aisdk.language",
-        { model: model("openai", "deployment"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.openai, ModelV2.ID.make("deployment")),
+            api: { id: ModelV2.ID.make("deployment"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       expect(calls).toEqual(["responses:deployment"])
@@ -101,11 +171,17 @@ describe("AzureCognitiveServicesPlugin", () => {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
       const sdk = fakeSelectorSdk(calls)
-      yield* addPlugin(plugin, AzureCognitiveServicesPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("azure-cognitive-services", "messages-deployment"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(
+              ProviderV2.ID.make("azure-cognitive-services"),
+              ModelV2.ID.make("messages-deployment"),
+            ),
+            api: { id: ModelV2.ID.make("messages-deployment"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { messages: sdk.messages, chat: sdk.chat, languageModel: sdk.languageModel },
           options: {},
         },
@@ -114,7 +190,10 @@ describe("AzureCognitiveServicesPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("azure-cognitive-services", "chat-deployment"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("azure-cognitive-services"), ModelV2.ID.make("chat-deployment")),
+            api: { id: ModelV2.ID.make("chat-deployment"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { chat: sdk.chat, languageModel: sdk.languageModel },
           options: {},
         },
@@ -123,7 +202,13 @@ describe("AzureCognitiveServicesPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("azure-cognitive-services", "language-deployment"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(
+              ProviderV2.ID.make("azure-cognitive-services"),
+              ModelV2.ID.make("language-deployment"),
+            ),
+            api: { id: ModelV2.ID.make("language-deployment"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { languageModel: sdk.languageModel },
           options: {},
         },

packages/core/test/plugin/provider-azure.test.ts

@@ -1,23 +1,73 @@
 import { describe, expect } from "bun:test"
+import type { LanguageModelV3 } from "@ai-sdk/provider"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { AzurePlugin } from "@opencode-ai/core/plugin/provider/azure"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, fakeSelectorSdk, it, model, provider, required, withEnv } from "./provider-helper"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: AzurePlugin.id, effect: AzurePlugin.effect(host) })
+})
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, fx: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    fx,
+    (previous) =>
+      Effect.sync(() => {
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        })
+      }),
+  )
+}
+
+function fakeSelectorSdk(calls: string[]) {
+  const make = (method: string) => (id: string) => {
+    calls.push(`${method}:${id}`)
+    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+  return {
+    responses: make("responses"),
+    messages: make("messages"),
+    chat: make("chat"),
+    languageModel: make("languageModel"),
+  }
+}
 
 describe("AzurePlugin", () => {
   it.effect("resolves resourceName from env", () =>
     withEnv({ AZURE_RESOURCE_NAME: "from-env" }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
         yield* catalog.transform((catalog) => {
           catalog.provider.update(ProviderV2.ID.azure, (item) => {
             item.api = { type: "aisdk", package: "@ai-sdk/azure" }
           })
         })
-        yield* addPlugin(plugin, AzurePlugin)
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.azure)).request.body.resourceName).toBe("from-env")
       }),
     ),
@@ -26,10 +76,10 @@ describe("AzurePlugin", () => {
   it.effect("keeps explicit resourceName over env and ignores other providers", () =>
     withEnv({ AZURE_RESOURCE_NAME: "from-env" }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
         yield* catalog.transform((catalog) => {
-          const azure = provider("azure", {
+          const azure = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.azure),
             api: { type: "aisdk", package: "@ai-sdk/azure" },
             request: { headers: {}, body: { resourceName: "from-config" } },
           })
@@ -39,7 +89,7 @@ describe("AzurePlugin", () => {
           })
           catalog.provider.update(ProviderV2.ID.openai, () => {})
         })
-        yield* addPlugin(plugin, AzurePlugin)
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.azure)).request.body.resourceName).toBe("from-config")
         expect(required(yield* catalog.provider.get(ProviderV2.ID.openai)).request.body.resourceName).toBeUndefined()
       }),
@@ -49,10 +99,10 @@ describe("AzurePlugin", () => {
   it.effect("falls back to env when configured resourceName is blank", () =>
     withEnv({ AZURE_RESOURCE_NAME: "from-env" }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
         yield* catalog.transform((catalog) => {
-          const azure = provider("azure", {
+          const azure = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.azure),
             api: { type: "aisdk", package: "@ai-sdk/azure" },
             request: { headers: {}, body: { resourceName: "" } },
           })
@@ -61,7 +111,7 @@ describe("AzurePlugin", () => {
             item.request = azure.request
           })
         })
-        yield* addPlugin(plugin, AzurePlugin)
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.azure)).request.body.resourceName).toBe("from-env")
       }),
     ),
@@ -70,10 +120,10 @@ describe("AzurePlugin", () => {
   it.effect("falls back to env when configured resourceName is whitespace", () =>
     withEnv({ AZURE_RESOURCE_NAME: "from-env" }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
         yield* catalog.transform((catalog) => {
-          const azure = provider("azure", {
+          const azure = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.azure),
             api: { type: "aisdk", package: "@ai-sdk/azure" },
             request: { headers: {}, body: { resourceName: "   " } },
           })
@@ -82,7 +132,7 @@ describe("AzurePlugin", () => {
             item.request = azure.request
           })
         })
-        yield* addPlugin(plugin, AzurePlugin)
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.azure)).request.body.resourceName).toBe("from-env")
       }),
     ),
@@ -92,11 +142,14 @@ describe("AzurePlugin", () => {
     withEnv({ AZURE_RESOURCE_NAME: undefined }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, AzurePlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("azure", "deployment"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.azure, ModelV2.ID.make("deployment")),
+              api: { id: ModelV2.ID.make("deployment"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/azure",
             options: { name: "azure", baseURL: "https://proxy.example.com/openai" },
           },
@@ -111,11 +164,18 @@ describe("AzurePlugin", () => {
     withEnv({ AZURE_RESOURCE_NAME: undefined }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, AzurePlugin)
+        yield* addPlugin()
         const exit = yield* plugin
           .trigger(
             "aisdk.sdk",
-            { model: model("azure", "deployment"), package: "@ai-sdk/azure", options: { name: "azure" } },
+            {
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.azure, ModelV2.ID.make("deployment")),
+                api: { id: ModelV2.ID.make("deployment"), type: "aisdk", package: "test-provider" },
+              }),
+              package: "@ai-sdk/azure",
+              options: { name: "azure" },
+            },
             {},
           )
           .pipe(Effect.exit)
@@ -128,10 +188,17 @@ describe("AzurePlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, AzurePlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
-        { model: model("azure", "deployment"), sdk: fakeSelectorSdk(calls), options: { useCompletionUrls: true } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.azure, ModelV2.ID.make("deployment")),
+            api: { id: ModelV2.ID.make("deployment"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: { useCompletionUrls: true },
+        },
         {},
       )
       expect(calls).toEqual(["chat:deployment"])
@@ -142,10 +209,17 @@ describe("AzurePlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, AzurePlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
-        { model: model("azure", "deployment"), sdk: fakeSelectorSdk(calls), options: { useCompletionUrls: true } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.azure, ModelV2.ID.make("deployment")),
+            api: { id: ModelV2.ID.make("deployment"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: { useCompletionUrls: true },
+        },
         {},
       )
       expect(calls).toEqual(["chat:deployment"])
@@ -156,11 +230,13 @@ describe("AzurePlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, AzurePlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("azure", "deployment", {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.azure, ModelV2.ID.make("deployment")),
+            api: { id: ModelV2.ID.make("deployment"), type: "aisdk", package: "test-provider" },
             request: { headers: {}, body: { useCompletionUrls: true } },
           }),
           sdk: fakeSelectorSdk(calls),
@@ -176,15 +252,29 @@ describe("AzurePlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, AzurePlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
-        { model: model("azure", "deployment"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.azure, ModelV2.ID.make("deployment")),
+            api: { id: ModelV2.ID.make("deployment"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       const ignored = yield* plugin.trigger(
         "aisdk.language",
-        { model: model("openai", "deployment"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.openai, ModelV2.ID.make("deployment")),
+            api: { id: ModelV2.ID.make("deployment"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       expect(calls).toEqual(["responses:deployment"])
@@ -200,11 +290,14 @@ describe("AzurePlugin", () => {
         calls.push(`${method}:${id}`)
         return { modelId: id, provider: method, specificationVersion: "v3" }
       }
-      yield* addPlugin(plugin, AzurePlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("azure", "messages-deployment"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.azure, ModelV2.ID.make("messages-deployment")),
+            api: { id: ModelV2.ID.make("messages-deployment"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { messages: make("messages"), chat: make("chat"), languageModel: make("languageModel") },
           options: {},
         },
@@ -212,7 +305,14 @@ describe("AzurePlugin", () => {
       )
       yield* plugin.trigger(
         "aisdk.language",
-        { model: model("azure", "language-deployment"), sdk: { languageModel: make("languageModel") }, options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.azure, ModelV2.ID.make("language-deployment")),
+            api: { id: ModelV2.ID.make("language-deployment"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: { languageModel: make("languageModel") },
+          options: {},
+        },
         {},
       )
       expect(calls).toEqual(["messages:messages-deployment", "languageModel:language-deployment"])

packages/core/test/plugin/provider-cerebras.test.ts

@@ -1,12 +1,22 @@
 import { describe, expect, mock } from "bun:test"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { CerebrasPlugin } from "@opencode-ai/core/plugin/provider/cerebras"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, it, model, required } from "./provider-helper"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
 
 const cerebrasOptions: Record<string, unknown>[] = []
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: CerebrasPlugin.id, effect: CerebrasPlugin.effect(host) })
+})
 
 void mock.module("@ai-sdk/cerebras", () => ({
   createCerebras: (options: Record<string, unknown>) => {
@@ -21,16 +31,15 @@ void mock.module("@ai-sdk/cerebras", () => ({
 describe("CerebrasPlugin", () => {
   it.effect("applies the legacy integration header", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, CerebrasPlugin)
       yield* catalog.transform((catalog) => {
         catalog.provider.update(ProviderV2.ID.make("cerebras"), (item) => {
           item.api = { type: "aisdk", package: "@ai-sdk/cerebras" }
           item.request.headers.Existing = "1"
         })
       })
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("cerebras"))).request.headers).toEqual({
+      yield* addPlugin()
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("cerebras")))?.request.headers).toEqual({
         Existing: "1",
         "X-Cerebras-3rd-Party-Integration": "opencode",
       })
@@ -39,11 +48,10 @@ describe("CerebrasPlugin", () => {
 
   it.effect("ignores non-Cerebras providers", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, CerebrasPlugin)
       yield* catalog.transform((catalog) => catalog.provider.update(ProviderV2.ID.make("groq"), () => {}))
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("groq"))).request.headers).toEqual({})
+      yield* addPlugin()
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("groq")))?.request.headers).toEqual({})
     }),
   )
 
@@ -51,11 +59,21 @@ describe("CerebrasPlugin", () => {
     Effect.gen(function* () {
       cerebrasOptions.length = 0
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, CerebrasPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-cerebras", "llama-4-scout-17b-16e-instruct"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(
+              ProviderV2.ID.make("custom-cerebras"),
+              ModelV2.ID.make("llama-4-scout-17b-16e-instruct"),
+            ),
+            api: {
+              id: ModelV2.ID.make("llama-4-scout-17b-16e-instruct"),
+              type: "aisdk",
+              package: "test-provider",
+            },
+          }),
           package: "@ai-sdk/cerebras",
           options: { name: "custom-cerebras", apiKey: "test" },
         },
@@ -70,11 +88,21 @@ describe("CerebrasPlugin", () => {
     Effect.gen(function* () {
       cerebrasOptions.length = 0
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, CerebrasPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-cerebras", "llama-4-scout-17b-16e-instruct"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(
+              ProviderV2.ID.make("custom-cerebras"),
+              ModelV2.ID.make("llama-4-scout-17b-16e-instruct"),
+            ),
+            api: {
+              id: ModelV2.ID.make("llama-4-scout-17b-16e-instruct"),
+              type: "aisdk",
+              package: "test-provider",
+            },
+          }),
           package: "@ai-sdk/cerebras",
           options: { name: "configured-cerebras", apiKey: "test" },
         },
@@ -88,11 +116,21 @@ describe("CerebrasPlugin", () => {
     Effect.gen(function* () {
       cerebrasOptions.length = 0
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, CerebrasPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-cerebras", "llama-4-scout-17b-16e-instruct"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(
+              ProviderV2.ID.make("custom-cerebras"),
+              ModelV2.ID.make("llama-4-scout-17b-16e-instruct"),
+            ),
+            api: {
+              id: ModelV2.ID.make("llama-4-scout-17b-16e-instruct"),
+              type: "aisdk",
+              package: "test-provider",
+            },
+          }),
           package: "@ai-sdk/groq",
           options: { name: "custom-cerebras", apiKey: "test" },
         },

packages/core/test/plugin/provider-cloudflare-ai-gateway.test.ts

@@ -1,8 +1,41 @@
 import { describe, expect, mock } from "bun:test"
 import { Effect } from "effect"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { CloudflareAIGatewayPlugin } from "@opencode-ai/core/plugin/provider/cloudflare-ai-gateway"
-import { addPlugin, it, model, withEnv } from "./provider-helper"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: CloudflareAIGatewayPlugin.id, effect: CloudflareAIGatewayPlugin.effect(host) })
+})
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, fx: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    fx,
+    (previous) =>
+      Effect.sync(() => {
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        })
+      }),
+  )
+}
 
 const aiGatewayCalls: Record<string, unknown>[] = []
 const unifiedCalls: string[] = []
@@ -78,11 +111,14 @@ describe("CloudflareAIGatewayPlugin", () => {
       () =>
         Effect.gen(function* () {
           const plugin = yield* PluginV2.Service
-          yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+          yield* addPlugin()
           const result = yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("cloudflare-ai-gateway", "openai/gpt-5"),
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-5")),
+                api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+              }),
               package: "ai-gateway-provider",
               options: { name: "cloudflare-ai-gateway" },
             },
@@ -98,12 +134,15 @@ describe("CloudflareAIGatewayPlugin", () => {
       Effect.gen(function* () {
         resetCalls()
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+        yield* addPlugin()
 
         yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-ai-gateway", "openai/gpt-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-5")),
+              api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "ai-gateway-provider",
             options: {
               name: "cloudflare-ai-gateway",
@@ -142,12 +181,15 @@ describe("CloudflareAIGatewayPlugin", () => {
       Effect.gen(function* () {
         resetCalls()
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+        yield* addPlugin()
 
         yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-ai-gateway", "openai/gpt-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-5")),
+              api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "ai-gateway-provider",
             options: {
               name: "cloudflare-ai-gateway",
@@ -171,12 +213,15 @@ describe("CloudflareAIGatewayPlugin", () => {
       Effect.gen(function* () {
         resetCalls()
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+        yield* addPlugin()
 
         yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-ai-gateway", "openai/gpt-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-5")),
+              api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "ai-gateway-provider",
             options: {
               name: "cloudflare-ai-gateway",
@@ -208,12 +253,15 @@ describe("CloudflareAIGatewayPlugin", () => {
         Effect.gen(function* () {
           resetCalls()
           const plugin = yield* PluginV2.Service
-          yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+          yield* addPlugin()
 
           yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("cloudflare-ai-gateway", "openai/gpt-5"),
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-5")),
+                api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+              }),
               package: "ai-gateway-provider",
               options: {
                 name: "cloudflare-ai-gateway",
@@ -239,12 +287,15 @@ describe("CloudflareAIGatewayPlugin", () => {
       Effect.gen(function* () {
         resetCalls()
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+        yield* addPlugin()
 
         yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-ai-gateway", "openai/gpt-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-5")),
+              api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "ai-gateway-provider",
             options: { name: "cloudflare-ai-gateway" },
           },
@@ -261,12 +312,15 @@ describe("CloudflareAIGatewayPlugin", () => {
       Effect.gen(function* () {
         resetCalls()
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+        yield* addPlugin()
 
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-ai-gateway", "openai/gpt-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-5")),
+              api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "ai-gateway-provider",
             options: { name: "cloudflare-ai-gateway" },
           },
@@ -284,12 +338,15 @@ describe("CloudflareAIGatewayPlugin", () => {
       Effect.gen(function* () {
         resetCalls()
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+        yield* addPlugin()
 
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-ai-gateway", "openai/gpt-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-5")),
+              api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "ai-gateway-provider",
             options: { name: "cloudflare-ai-gateway" },
           },
@@ -313,12 +370,15 @@ describe("CloudflareAIGatewayPlugin", () => {
         Effect.gen(function* () {
           resetCalls()
           const plugin = yield* PluginV2.Service
-          yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+          yield* addPlugin()
 
           const result = yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("cloudflare-ai-gateway", "openai/gpt-5"),
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-5")),
+                api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+              }),
               package: "ai-gateway-provider",
               options: { name: "cloudflare-ai-gateway", baseURL: "https://proxy.example/v1" },
             },
@@ -336,12 +396,22 @@ describe("CloudflareAIGatewayPlugin", () => {
       Effect.gen(function* () {
         resetCalls()
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+        yield* addPlugin()
 
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-ai-gateway", "anthropic/claude-sonnet-4-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(
+                ProviderV2.ID.make("cloudflare-ai-gateway"),
+                ModelV2.ID.make("anthropic/claude-sonnet-4-5"),
+              ),
+              api: {
+                id: ModelV2.ID.make("anthropic/claude-sonnet-4-5"),
+                type: "aisdk",
+                package: "test-provider",
+              },
+            }),
             package: "ai-gateway-provider",
             options: { name: "cloudflare-ai-gateway" },
           },
@@ -364,12 +434,15 @@ describe("CloudflareAIGatewayPlugin", () => {
       Effect.gen(function* () {
         resetCalls()
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareAIGatewayPlugin)
+        yield* addPlugin()
 
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-ai-gateway", "openai/gpt-5"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-ai-gateway"), ModelV2.ID.make("openai/gpt-5")),
+              api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/openai-compatible",
             options: { name: "cloudflare-ai-gateway" },
           },

packages/core/test/plugin/provider-cloudflare-workers-ai.test.ts

@@ -3,9 +3,59 @@ import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { CloudflareWorkersAIPlugin } from "@opencode-ai/core/plugin/provider/cloudflare-workers-ai"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, fakeSelectorSdk, it, model, required, withEnv } from "./provider-helper"
+import type { LanguageModelV3 } from "@ai-sdk/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: CloudflareWorkersAIPlugin.id, effect: CloudflareWorkersAIPlugin.effect(host) })
+})
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, effect: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    effect,
+    (previous) =>
+      Effect.sync(() =>
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        }),
+      ),
+  )
+}
+
+function fakeSelectorSdk(calls: string[]) {
+  const make = (method: string) => (id: string) => {
+    calls.push(`${method}:${id}`)
+    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+  return {
+    responses: make("responses"),
+    messages: make("messages"),
+    chat: make("chat"),
+    languageModel: make("languageModel"),
+  }
+}
 
 function cloudflareLanguage(sdk: unknown, modelID = "@cf/model") {
   return (sdk as { languageModel: (id: string) => { config: CloudflareConfig; provider: string } }).languageModel(
@@ -37,12 +87,15 @@ describe("CloudflareWorkersAIPlugin", () => {
             provider.api = { type: "aisdk", package: "test-provider" }
           }),
         )
-        yield* addPlugin(plugin, CloudflareWorkersAIPlugin)
+        yield* addPlugin()
         const provider = required(yield* catalog.provider.get(ProviderV2.ID.make("cloudflare-workers-ai")))
         const sdk = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-workers-ai", "@cf/model", { api: provider.api }),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-workers-ai"), ModelV2.ID.make("@cf/model")),
+              api: { id: ModelV2.ID.make("@cf/model"), ...provider.api },
+            }),
             package: "@ai-sdk/openai-compatible",
             options: { name: "cloudflare-workers-ai", headers: { custom: "header" } },
           },
@@ -61,14 +114,13 @@ describe("CloudflareWorkersAIPlugin", () => {
   it.effect("preserves a configured endpoint URL instead of deriving one from account ID", () =>
     withEnv({ CLOUDFLARE_ACCOUNT_ID: "acct" }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
         yield* catalog.transform((catalog) =>
           catalog.provider.update(ProviderV2.ID.make("cloudflare-workers-ai"), (provider) => {
             provider.api = { type: "aisdk", package: "test-provider", url: "https://proxy.example/v1" }
           }),
         )
-        yield* addPlugin(plugin, CloudflareWorkersAIPlugin)
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.make("cloudflare-workers-ai"))).api).toEqual({
           type: "aisdk",
           package: "test-provider",
@@ -82,12 +134,18 @@ describe("CloudflareWorkersAIPlugin", () => {
     withEnv({ CLOUDFLARE_ACCOUNT_ID: undefined, CLOUDFLARE_API_KEY: "key" }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareWorkersAIPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-workers-ai", "@cf/model", {
-              api: { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://proxy.example/v1" },
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-workers-ai"), ModelV2.ID.make("@cf/model")),
+              api: {
+                id: ModelV2.ID.make("@cf/model"),
+                type: "aisdk",
+                package: "@ai-sdk/openai-compatible",
+                url: "https://proxy.example/v1",
+              },
             }),
             package: "@ai-sdk/openai-compatible",
             options: { name: "cloudflare-workers-ai", baseURL: "https://proxy.example/v1" },
@@ -102,7 +160,6 @@ describe("CloudflareWorkersAIPlugin", () => {
   it.effect("uses env account ID over configured account ID", () =>
     withEnv({ CLOUDFLARE_ACCOUNT_ID: "env-acct" }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
         yield* catalog.transform((catalog) =>
           catalog.provider.update(ProviderV2.ID.make("cloudflare-workers-ai"), (provider) => {
@@ -110,7 +167,7 @@ describe("CloudflareWorkersAIPlugin", () => {
             provider.request.body.accountId = "configured-acct"
           }),
         )
-        yield* addPlugin(plugin, CloudflareWorkersAIPlugin)
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.make("cloudflare-workers-ai"))).api).toEqual({
           type: "aisdk",
           package: "test-provider",
@@ -124,12 +181,18 @@ describe("CloudflareWorkersAIPlugin", () => {
     withEnv({ CLOUDFLARE_ACCOUNT_ID: "acct", CLOUDFLARE_API_KEY: "env-key" }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareWorkersAIPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-workers-ai", "@cf/model", {
-              api: { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://proxy.example/v1" },
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-workers-ai"), ModelV2.ID.make("@cf/model")),
+              api: {
+                id: ModelV2.ID.make("@cf/model"),
+                type: "aisdk",
+                package: "@ai-sdk/openai-compatible",
+                url: "https://proxy.example/v1",
+              },
             }),
             package: "@ai-sdk/openai-compatible",
             options: {
@@ -153,12 +216,14 @@ describe("CloudflareWorkersAIPlugin", () => {
     withEnv({ CLOUDFLARE_ACCOUNT_ID: "acct", CLOUDFLARE_API_KEY: "key" }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareWorkersAIPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-workers-ai", "@cf/model", {
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-workers-ai"), ModelV2.ID.make("@cf/model")),
               api: {
+                id: ModelV2.ID.make("@cf/model"),
                 type: "aisdk",
                 package: "@ai-sdk/openai-compatible",
                 url: "https://api.cloudflare.com/client/v4/accounts/${CLOUDFLARE_ACCOUNT_ID}/ai/v1",
@@ -183,11 +248,14 @@ describe("CloudflareWorkersAIPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, CloudflareWorkersAIPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("cloudflare-workers-ai", "alias", { api: { id: ModelV2.ID.make("@cf/api-model") } }),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-workers-ai"), ModelV2.ID.make("alias")),
+            api: { id: ModelV2.ID.make("@cf/api-model"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
@@ -202,12 +270,18 @@ describe("CloudflareWorkersAIPlugin", () => {
     withEnv({ CLOUDFLARE_ACCOUNT_ID: "acct", CLOUDFLARE_API_KEY: "key" }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, CloudflareWorkersAIPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("cloudflare-workers-ai", "@cf/model", {
-              api: { type: "aisdk", package: "@ai-sdk/anthropic", url: "https://proxy.example/v1" },
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-workers-ai"), ModelV2.ID.make("@cf/model")),
+              api: {
+                id: ModelV2.ID.make("@cf/model"),
+                type: "aisdk",
+                package: "@ai-sdk/anthropic",
+                url: "https://proxy.example/v1",
+              },
             }),
             package: "@ai-sdk/anthropic",
             options: { name: "cloudflare-workers-ai" },

packages/core/test/plugin/provider-cohere.test.ts

@@ -2,10 +2,34 @@ import { describe, expect, mock } from "bun:test"
 import { Effect } from "effect"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { CoherePlugin } from "@opencode-ai/core/plugin/provider/cohere"
-import { addPlugin, fakeSelectorSdk, it, model } from "./provider-helper"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import type { LanguageModelV3 } from "@ai-sdk/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
 
 const cohereOptions: Record<string, any>[] = []
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: CoherePlugin.id, effect: CoherePlugin.effect(host) })
+})
+
+function fakeSelectorSdk(calls: string[]) {
+  const make = (method: string) => (id: string) => {
+    calls.push(`${method}:${id}`)
+    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+  return {
+    responses: make("responses"),
+    messages: make("messages"),
+    chat: make("chat"),
+    languageModel: make("languageModel"),
+  }
+}
 
 void mock.module("@ai-sdk/cohere", () => ({
   createCohere: (options: Record<string, any>) => {
@@ -24,18 +48,32 @@ describe("CoherePlugin", () => {
   it.effect("creates a Cohere SDK only for @ai-sdk/cohere", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, CoherePlugin)
+      yield* addPlugin()
 
       const ignored = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("cohere", "command"), package: "@ai-sdk/openai-compatible", options: { name: "cohere" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("cohere"), ModelV2.ID.make("command")),
+            api: { id: ModelV2.ID.make("command"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/openai-compatible",
+          options: { name: "cohere" },
+        },
         {},
       )
       expect(ignored.sdk).toBeUndefined()
 
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("cohere", "command"), package: "@ai-sdk/cohere", options: { name: "cohere" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("cohere"), ModelV2.ID.make("command")),
+            api: { id: ModelV2.ID.make("command"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/cohere",
+          options: { name: "cohere" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -45,11 +83,14 @@ describe("CoherePlugin", () => {
   it.effect("uses the model provider ID as the bundled SDK name", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, CoherePlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-cohere", "command-r-plus"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-cohere"), ModelV2.ID.make("command-r-plus")),
+            api: { id: ModelV2.ID.make("command-r-plus"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/cohere",
           options: { name: "custom-cohere", apiKey: "test", baseURL: "https://cohere.example" },
         },
@@ -70,10 +111,17 @@ describe("CoherePlugin", () => {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
       const sdk = fakeSelectorSdk(calls)
-      yield* addPlugin(plugin, CoherePlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.language",
-        { model: model("cohere", "alias", { api: { id: ModelV2.ID.make("command-r-plus") } }), sdk, options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("cohere"), ModelV2.ID.make("alias")),
+            api: { id: ModelV2.ID.make("command-r-plus"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk,
+          options: {},
+        },
         {},
       )
 

packages/core/test/plugin/provider-deepinfra.test.ts

@@ -1,20 +1,25 @@
 import { describe, expect, mock } from "bun:test"
-import { Effect, Layer } from "effect"
-import { AISDK } from "@opencode-ai/core/aisdk"
-import { EventV2 } from "@opencode-ai/core/event"
+import { Effect } from "effect"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { DeepInfraPlugin } from "@opencode-ai/core/plugin/provider/deepinfra"
+import { ProviderV2 } from "@opencode-ai/core/provider"
 import { testEffect } from "../lib/effect"
-import { addPlugin, it, model } from "./provider-helper"
+import { PluginTestLayer } from "./fixture"
 
-const itAISDK = testEffect(
-  Layer.provideMerge(AISDK.layer, PluginV2.locationLayer.pipe(Layer.provide(EventV2.defaultLayer))),
-)
-const deepinfraOptions: Record<string, any>[] = []
+const it = testEffect(PluginTestLayer)
+const deepinfraOptions: Record<string, unknown>[] = []
 const deepinfraLanguageModels: string[] = []
 
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: DeepInfraPlugin.id, effect: DeepInfraPlugin.effect(host) })
+})
+
 void mock.module("@ai-sdk/deepinfra", () => ({
-  createDeepInfra: (options: Record<string, any>) => {
+  createDeepInfra: (options: Record<string, unknown>) => {
     const captured = { ...options }
     deepinfraOptions.push(captured)
     return {
@@ -36,10 +41,17 @@ describe("DeepInfraPlugin", () => {
     Effect.gen(function* () {
       resetDeepInfraMock()
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, DeepInfraPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("deepinfra", "model"), package: "@ai-sdk/deepinfra", options: { name: "deepinfra" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("deepinfra"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "@ai-sdk/deepinfra" },
+          }),
+          package: "@ai-sdk/deepinfra",
+          options: { name: "deepinfra" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -50,11 +62,14 @@ describe("DeepInfraPlugin", () => {
     Effect.gen(function* () {
       resetDeepInfraMock()
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, DeepInfraPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-deepinfra", "model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-deepinfra"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "@ai-sdk/deepinfra" },
+          }),
           package: "@ai-sdk/deepinfra",
           options: { name: "custom-deepinfra", apiKey: "test" },
         },
@@ -69,11 +84,14 @@ describe("DeepInfraPlugin", () => {
     Effect.gen(function* () {
       resetDeepInfraMock()
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, DeepInfraPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("deepinfra", "model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("deepinfra"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "@ai-sdk/deepinfra" },
+          }),
           package: "@ai-sdk/deepinfra",
           options: { name: "deepinfra", apiKey: "test" },
         },
@@ -88,7 +106,7 @@ describe("DeepInfraPlugin", () => {
     Effect.gen(function* () {
       resetDeepInfraMock()
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, DeepInfraPlugin)
+      yield* addPlugin()
       const packages = [
         "unmatched-package",
         "@ai-sdk/deepinfra-compatible",
@@ -98,7 +116,14 @@ describe("DeepInfraPlugin", () => {
         Effect.gen(function* () {
           const ignored = yield* plugin.trigger(
             "aisdk.sdk",
-            { model: model("deepinfra", "model"), package: item, options: { name: "deepinfra" } },
+            {
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.make("deepinfra"), ModelV2.ID.make("model")),
+                api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "@ai-sdk/deepinfra" },
+              }),
+              package: item,
+              options: { name: "deepinfra" },
+            },
             {},
           )
           expect(ignored.sdk).toBeUndefined()
@@ -106,7 +131,14 @@ describe("DeepInfraPlugin", () => {
       )
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("deepinfra", "model"), package: "@ai-sdk/deepinfra", options: { name: "deepinfra" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("deepinfra"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "@ai-sdk/deepinfra" },
+          }),
+          package: "@ai-sdk/deepinfra",
+          options: { name: "deepinfra" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -114,17 +146,36 @@ describe("DeepInfraPlugin", () => {
     }),
   )
 
-  itAISDK.effect("uses the default languageModel selection for DeepInfra models", () =>
+  it.effect("uses the default languageModel selection for DeepInfra models", () =>
     Effect.gen(function* () {
       resetDeepInfraMock()
       const plugin = yield* PluginV2.Service
-      const aisdk = yield* AISDK.Service
-      yield* addPlugin(plugin, DeepInfraPlugin)
-      const language = yield* aisdk.language(
-        model("deepinfra", "meta-llama/Llama-3.3-70B-Instruct", {
-          api: { type: "aisdk", package: "@ai-sdk/deepinfra" },
-        }),
+      yield* addPlugin()
+      const sdkEvent = yield* plugin.trigger(
+        "aisdk.sdk",
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(
+              ProviderV2.ID.make("deepinfra"),
+              ModelV2.ID.make("meta-llama/Llama-3.3-70B-Instruct"),
+            ),
+            api: {
+              id: ModelV2.ID.make("meta-llama/Llama-3.3-70B-Instruct"),
+              type: "aisdk",
+              package: "@ai-sdk/deepinfra",
+            },
+          }),
+          package: "@ai-sdk/deepinfra",
+          options: { name: "deepinfra" },
+        },
+        {},
       )
+      const result = yield* plugin.trigger(
+        "aisdk.language",
+        { model: sdkEvent.model, sdk: sdkEvent.sdk, options: sdkEvent.options },
+        {},
+      )
+      const language = result.language ?? result.sdk.languageModel(result.model.api.id)
       expect(language.provider).toBe("deepinfra.chat")
       expect(deepinfraLanguageModels).toEqual(["meta-llama/Llama-3.3-70B-Instruct"])
     }),

packages/core/test/plugin/provider-dynamic.test.ts

@@ -1,43 +1,40 @@
 import { Npm } from "@opencode-ai/core/npm"
 import { describe, expect } from "bun:test"
-import { Cause, Effect, Layer, Option } from "effect"
+import { Cause, Effect, Layer } from "effect"
 import fs from "fs/promises"
 import os from "os"
 import path from "path"
 import { fileURLToPath } from "url"
 import { AISDK } from "@opencode-ai/core/aisdk"
-import { EventV2 } from "@opencode-ai/core/event"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { DynamicProviderPlugin } from "@opencode-ai/core/plugin/provider/dynamic"
+import { ProviderV2 } from "@opencode-ai/core/provider"
 import { testEffect } from "../lib/effect"
-import { host } from "./host"
-import { fixtureProvider, it, model, npmLayer } from "./provider-helper"
+import { PluginTestLayer } from "./fixture"
 
+const fixtureProvider = new URL("./fixtures/provider-factory.ts", import.meta.url).href
 const fixtureProviderPath = fileURLToPath(fixtureProvider)
-const itWithAISDK = testEffect(
-  AISDK.layer.pipe(Layer.provideMerge(PluginV2.locationLayer.pipe(Layer.provide(EventV2.defaultLayer)))),
-)
+const it = testEffect(PluginTestLayer)
+const itWithAISDK = testEffect(AISDK.layer.pipe(Layer.provideMerge(PluginTestLayer)))
 
-function npmEntrypointLayer(entrypoint?: string) {
-  return Layer.succeed(
-    Npm.Service,
-    Npm.Service.of({
-      add: () => Effect.succeed({ directory: "", entrypoint }),
-      install: () => Effect.void,
-      which: () => Effect.succeed(undefined),
-    }),
-  )
+function npmEntrypoint(entrypoint?: string) {
+  return Npm.Service.of({
+    add: () => Effect.succeed({ directory: "", entrypoint }),
+    install: () => Effect.void,
+    which: () => Effect.succeed(undefined),
+  })
 }
 
-function dynamicPlugin(layer = npmLayer) {
-  return {
+const addPlugin = Effect.fn(function* (npm?: Npm.Interface) {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({
     id: DynamicProviderPlugin.id,
-    effect: Effect.gen(function* () {
-      yield* DynamicProviderPlugin.effect(host({ npm: yield* Npm.Service }))
-    }).pipe(Effect.provide(layer)),
-  }
-}
+    effect: DynamicProviderPlugin.effect(npm ? { ...host, npm } : host),
+  })
+})
 
 function tempEntrypoint(source: string) {
   return Effect.acquireRelease(
@@ -55,11 +52,14 @@ describe("DynamicProviderPlugin", () => {
   it.effect("creates an SDK from a provider factory export", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* plugin.add(dynamicPlugin())
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom", "test-model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom"), ModelV2.ID.make("test-model")),
+            api: { id: ModelV2.ID.make("test-model"), type: "aisdk", package: fixtureProvider },
+          }),
           package: fixtureProvider,
           options: { name: "custom", marker: "dynamic" },
         },
@@ -74,11 +74,14 @@ describe("DynamicProviderPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const sdk = { marker: "existing" }
-      yield* plugin.add(dynamicPlugin())
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom", "test-model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom"), ModelV2.ID.make("test-model")),
+            api: { id: ModelV2.ID.make("test-model"), type: "aisdk", package: fixtureProvider },
+          }),
           package: fixtureProvider,
           options: { name: "custom", marker: "dynamic" },
         },
@@ -91,11 +94,14 @@ describe("DynamicProviderPlugin", () => {
   it.effect("injects the provider ID as the SDK factory name", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* plugin.add(dynamicPlugin())
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-provider", "test-model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-provider"), ModelV2.ID.make("test-model")),
+            api: { id: ModelV2.ID.make("test-model"), type: "aisdk", package: fixtureProvider },
+          }),
           package: fixtureProvider,
           options: { name: "custom-provider", marker: "dynamic" },
         },
@@ -108,11 +114,14 @@ describe("DynamicProviderPlugin", () => {
   it.effect("loads npm packages through their resolved import entrypoint", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* plugin.add(dynamicPlugin(npmEntrypointLayer(fixtureProviderPath)))
+      yield* addPlugin(npmEntrypoint(fixtureProviderPath))
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("npm-provider", "test-model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("npm-provider"), ModelV2.ID.make("test-model")),
+            api: { id: ModelV2.ID.make("test-model"), type: "aisdk", package: "fixture-provider" },
+          }),
           package: "fixture-provider",
           options: { name: "npm-provider", marker: "npm" },
         },
@@ -126,9 +135,14 @@ describe("DynamicProviderPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const aisdk = yield* AISDK.Service
-      yield* plugin.add(dynamicPlugin(npmEntrypointLayer()))
+      yield* addPlugin(npmEntrypoint())
       const exit = yield* aisdk
-        .language(model("missing-entrypoint", "alias", { api: { type: "aisdk", package: "fixture-provider" } }))
+        .language(
+          new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("missing-entrypoint"), ModelV2.ID.make("alias")),
+            api: { id: ModelV2.ID.make("alias"), type: "aisdk", package: "fixture-provider" },
+          }),
+        )
         .pipe(Effect.exit)
       expect(exit._tag).toBe("Failure")
       if (exit._tag === "Failure") expect(Cause.prettyErrors(exit.cause).join("\n")).toContain("AISDK.InitError")
@@ -139,10 +153,13 @@ describe("DynamicProviderPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const aisdk = yield* AISDK.Service
-      yield* plugin.add(dynamicPlugin())
+      yield* addPlugin()
       const exit = yield* aisdk
         .language(
-          model("bad-import", "alias", { api: { type: "aisdk", package: "file:///missing/provider-factory.js" } }),
+          new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("bad-import"), ModelV2.ID.make("alias")),
+            api: { id: ModelV2.ID.make("alias"), type: "aisdk", package: "file:///missing/provider-factory.js" },
+          }),
         )
         .pipe(Effect.exit)
       expect(exit._tag).toBe("Failure")
@@ -155,9 +172,14 @@ describe("DynamicProviderPlugin", () => {
       const plugin = yield* PluginV2.Service
       const aisdk = yield* AISDK.Service
       const tmp = yield* tempEntrypoint("export const notAProviderFactory = true\n")
-      yield* plugin.add(dynamicPlugin(npmEntrypointLayer(tmp.entrypoint)))
+      yield* addPlugin(npmEntrypoint(tmp.entrypoint))
       const exit = yield* aisdk
-        .language(model("missing-factory", "alias", { api: { type: "aisdk", package: "fixture-provider" } }))
+        .language(
+          new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("missing-factory"), ModelV2.ID.make("alias")),
+            api: { id: ModelV2.ID.make("alias"), type: "aisdk", package: "fixture-provider" },
+          }),
+        )
         .pipe(Effect.exit)
       expect(exit._tag).toBe("Failure")
       if (exit._tag === "Failure") expect(Cause.prettyErrors(exit.cause).join("\n")).toContain("AISDK.InitError")
@@ -168,9 +190,10 @@ describe("DynamicProviderPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const aisdk = yield* AISDK.Service
-      yield* plugin.add(dynamicPlugin())
+      yield* addPlugin()
       const language = yield* aisdk.language(
-        model("custom", "alias", {
+        new ModelV2.Info({
+          ...ModelV2.Info.empty(ProviderV2.ID.make("custom"), ModelV2.ID.make("alias")),
           api: { id: ModelV2.ID.make("test-model-api"), type: "aisdk", package: fixtureProvider },
         }),
       )

packages/core/test/plugin/provider-gateway.test.ts

@@ -1,11 +1,22 @@
 import { describe, expect, mock } from "bun:test"
 import { Effect } from "effect"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { GatewayPlugin } from "@opencode-ai/core/plugin/provider/gateway"
-import { addPlugin, it, model } from "./provider-helper"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
 
 const gatewayCalls: Record<string, unknown>[] = []
 const vercelGatewayModels = ["anthropic/claude-sonnet-4", "openai/gpt-5", "google/gemini-2.5-pro"]
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: GatewayPlugin.id, effect: GatewayPlugin.effect(host) })
+})
 
 mock.module("@ai-sdk/gateway", () => ({
   createGateway(options: Record<string, unknown>) {
@@ -27,10 +38,17 @@ describe("GatewayPlugin", () => {
     Effect.gen(function* () {
       gatewayCalls.length = 0
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GatewayPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("gateway", "model"), package: "@ai-sdk/gateway", options: { name: "gateway" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("gateway"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/gateway",
+          options: { name: "gateway" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -42,12 +60,19 @@ describe("GatewayPlugin", () => {
     Effect.gen(function* () {
       gatewayCalls.length = 0
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GatewayPlugin)
+      yield* addPlugin()
 
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("vercel", "anthropic/claude-sonnet-4"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("vercel"), ModelV2.ID.make("anthropic/claude-sonnet-4")),
+            api: {
+              id: ModelV2.ID.make("anthropic/claude-sonnet-4"),
+              type: "aisdk",
+              package: "test-provider",
+            },
+          }),
           package: "@ai-sdk/gateway",
           options: { name: "vercel", apiKey: "test-key" },
         },
@@ -63,19 +88,33 @@ describe("GatewayPlugin", () => {
     Effect.gen(function* () {
       gatewayCalls.length = 0
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GatewayPlugin)
+      yield* addPlugin()
 
       for (const modelID of vercelGatewayModels) {
         const ignored = yield* plugin.trigger(
           "aisdk.sdk",
-          { model: model("vercel", modelID), package: "@ai-sdk/vercel", options: { name: "vercel" } },
+          {
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("vercel"), ModelV2.ID.make(modelID)),
+              api: { id: ModelV2.ID.make(modelID), type: "aisdk", package: "test-provider" },
+            }),
+            package: "@ai-sdk/vercel",
+            options: { name: "vercel" },
+          },
           {},
         )
         expect(ignored.sdk).toBeUndefined()
 
         const result = yield* plugin.trigger(
           "aisdk.sdk",
-          { model: model("vercel", modelID), package: "@ai-sdk/gateway", options: { name: "vercel" } },
+          {
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("vercel"), ModelV2.ID.make(modelID)),
+              api: { id: ModelV2.ID.make(modelID), type: "aisdk", package: "test-provider" },
+            }),
+            package: "@ai-sdk/gateway",
+            options: { name: "vercel" },
+          },
           {},
         )
         expect(result.sdk).toBeDefined()

packages/core/test/plugin/provider-github-copilot.test.ts

@@ -3,19 +3,51 @@ import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { GithubCopilotPlugin } from "@opencode-ai/core/plugin/provider/github-copilot"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, fakeSelectorSdk, it, model, required } from "./provider-helper"
+import type { LanguageModelV3 } from "@ai-sdk/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: GithubCopilotPlugin.id, effect: GithubCopilotPlugin.effect(host) })
+})
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
+
+function fakeSelectorSdk(calls: string[]) {
+  const make = (method: string) => (id: string) => {
+    calls.push(`${method}:${id}`)
+    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+  return {
+    responses: make("responses"),
+    messages: make("messages"),
+    chat: make("chat"),
+    languageModel: make("languageModel"),
+  }
+}
 
 describe("GithubCopilotPlugin", () => {
   it.effect("creates the bundled Copilot SDK for the GitHub Copilot package", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GithubCopilotPlugin)
+      yield* addPlugin()
       const ignored = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("github-copilot", "gpt-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("gpt-5")),
+            api: { id: ModelV2.ID.make("gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/openai-compatible",
           options: { name: "github-copilot" },
         },
@@ -24,7 +56,10 @@ describe("GithubCopilotPlugin", () => {
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("github-copilot", "gpt-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("gpt-5")),
+            api: { id: ModelV2.ID.make("gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/github-copilot",
           options: { name: "github-copilot" },
         },
@@ -39,11 +74,14 @@ describe("GithubCopilotPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, GithubCopilotPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("github-copilot", "claude-sonnet-4"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("claude-sonnet-4")),
+            api: { id: ModelV2.ID.make("claude-sonnet-4"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: {},
         },
@@ -57,11 +95,14 @@ describe("GithubCopilotPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, GithubCopilotPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("github-copilot", "alias", { api: { id: ModelV2.ID.make("claude-sonnet-4") } }),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("alias")),
+            api: { id: ModelV2.ID.make("claude-sonnet-4"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: {},
         },
@@ -75,30 +116,65 @@ describe("GithubCopilotPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, GithubCopilotPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
-        { model: model("github-copilot", "gpt-5"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("gpt-5")),
+            api: { id: ModelV2.ID.make("gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       yield* plugin.trigger(
         "aisdk.language",
-        { model: model("github-copilot", "gpt-5.1-codex"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("gpt-5.1-codex")),
+            api: { id: ModelV2.ID.make("gpt-5.1-codex"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       yield* plugin.trigger(
         "aisdk.language",
-        { model: model("github-copilot", "gpt-4o"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("gpt-4o")),
+            api: { id: ModelV2.ID.make("gpt-4o"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       yield* plugin.trigger(
         "aisdk.language",
-        { model: model("github-copilot", "gpt-5-mini"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("gpt-5-mini")),
+            api: { id: ModelV2.ID.make("gpt-5-mini"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       yield* plugin.trigger(
         "aisdk.language",
-        { model: model("github-copilot", "gpt-5-mini-2025-08-07"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("gpt-5-mini-2025-08-07")),
+            api: { id: ModelV2.ID.make("gpt-5-mini-2025-08-07"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       expect(calls).toEqual([
@@ -115,11 +191,14 @@ describe("GithubCopilotPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, GithubCopilotPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("github-copilot", "default", { api: { id: ModelV2.ID.make("gpt-5") } }),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("default")),
+            api: { id: ModelV2.ID.make("gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
@@ -128,7 +207,10 @@ describe("GithubCopilotPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("github-copilot", "small", { api: { id: ModelV2.ID.make("gpt-5-mini") } }),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("small")),
+            api: { id: ModelV2.ID.make("gpt-5-mini"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
@@ -137,7 +219,10 @@ describe("GithubCopilotPlugin", () => {
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("github-copilot", "sonnet", { api: { id: ModelV2.ID.make("claude-sonnet-4") } }),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("sonnet")),
+            api: { id: ModelV2.ID.make("claude-sonnet-4"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },
@@ -149,30 +234,30 @@ describe("GithubCopilotPlugin", () => {
 
   it.effect("disables gpt-5-chat-latest before Copilot language selection", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, GithubCopilotPlugin)
       yield* catalog.transform((catalog) => {
         catalog.provider.update(ProviderV2.ID.make("github-copilot"), () => {})
         catalog.model.update(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("gpt-5-chat-latest"), () => {})
       })
+      yield* addPlugin()
       expect(
-        required(yield* catalog.model.get(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("gpt-5-chat-latest"))).enabled,
+        required(yield* catalog.model.get(ProviderV2.ID.make("github-copilot"), ModelV2.ID.make("gpt-5-chat-latest")))
+          .enabled,
       ).toBe(false)
     }),
   )
 
   it.effect("does not disable gpt-5-chat-latest for non-Copilot providers", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, GithubCopilotPlugin)
       yield* catalog.transform((catalog) => {
         catalog.provider.update(ProviderV2.ID.make("custom-copilot"), () => {})
         catalog.model.update(ProviderV2.ID.make("custom-copilot"), ModelV2.ID.make("gpt-5-chat-latest"), () => {})
       })
+      yield* addPlugin()
       expect(
-        required(yield* catalog.model.get(ProviderV2.ID.make("custom-copilot"), ModelV2.ID.make("gpt-5-chat-latest"))).enabled,
+        required(yield* catalog.model.get(ProviderV2.ID.make("custom-copilot"), ModelV2.ID.make("gpt-5-chat-latest")))
+          .enabled,
       ).toBe(true)
     }),
   )
@@ -181,10 +266,17 @@ describe("GithubCopilotPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, GithubCopilotPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.language",
-        { model: model("openai", "gpt-5"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("openai"), ModelV2.ID.make("gpt-5")),
+            api: { id: ModelV2.ID.make("gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       expect(calls).toEqual([])

packages/core/test/plugin/provider-gitlab.test.ts

@@ -1,12 +1,43 @@
 import { describe, expect, mock } from "bun:test"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { GitLabPlugin } from "@opencode-ai/core/plugin/provider/gitlab"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, it, model, required, withEnv } from "./provider-helper"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
 
 const gitlabSDKOptions: Record<string, unknown>[] = []
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: GitLabPlugin.id, effect: GitLabPlugin.effect(host) })
+})
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, effect: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    effect,
+    (previous) =>
+      Effect.sync(() =>
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        }),
+      ),
+  )
+}
 
 void mock.module("gitlab-ai-provider", () => ({
   VERSION: "test-version",
@@ -32,10 +63,17 @@ describe("GitLabPlugin", () => {
         Effect.gen(function* () {
           gitlabSDKOptions.length = 0
           const plugin = yield* PluginV2.Service
-          yield* addPlugin(plugin, GitLabPlugin)
+          yield* addPlugin()
           yield* plugin.trigger(
             "aisdk.sdk",
-            { model: model("gitlab", "claude"), package: "gitlab-ai-provider", options: { name: "gitlab" } },
+            {
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.make("gitlab"), ModelV2.ID.make("claude")),
+                api: { id: ModelV2.ID.make("claude"), type: "aisdk", package: "test-provider" },
+              }),
+              package: "gitlab-ai-provider",
+              options: { name: "gitlab" },
+            },
             {},
           )
           expect(gitlabSDKOptions).toHaveLength(1)
@@ -65,10 +103,17 @@ describe("GitLabPlugin", () => {
         Effect.gen(function* () {
           gitlabSDKOptions.length = 0
           const plugin = yield* PluginV2.Service
-          yield* addPlugin(plugin, GitLabPlugin)
+          yield* addPlugin()
           yield* plugin.trigger(
             "aisdk.sdk",
-            { model: model("gitlab", "claude"), package: "gitlab-ai-provider", options: { name: "gitlab" } },
+            {
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.make("gitlab"), ModelV2.ID.make("claude")),
+                api: { id: ModelV2.ID.make("claude"), type: "aisdk", package: "test-provider" },
+              }),
+              package: "gitlab-ai-provider",
+              options: { name: "gitlab" },
+            },
             {},
           )
           expect(gitlabSDKOptions[0].instanceUrl).toBe("https://env.gitlab.example")
@@ -86,11 +131,14 @@ describe("GitLabPlugin", () => {
         Effect.gen(function* () {
           gitlabSDKOptions.length = 0
           const plugin = yield* PluginV2.Service
-          yield* addPlugin(plugin, GitLabPlugin)
+          yield* addPlugin()
           yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("gitlab", "claude"),
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.make("gitlab"), ModelV2.ID.make("claude")),
+                api: { id: ModelV2.ID.make("claude"), type: "aisdk", package: "test-provider" },
+              }),
               package: "gitlab-ai-provider",
               options: {
                 name: "gitlab",
@@ -127,10 +175,17 @@ describe("GitLabPlugin", () => {
     Effect.gen(function* () {
       gitlabSDKOptions.length = 0
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GitLabPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("gitlab", "claude"), package: "@ai-sdk/openai", options: { name: "gitlab" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("gitlab"), ModelV2.ID.make("claude")),
+            api: { id: ModelV2.ID.make("claude"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/openai",
+          options: { name: "gitlab" },
+        },
         {},
       )
       expect(result.sdk).toBeUndefined()
@@ -142,11 +197,13 @@ describe("GitLabPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: [string, unknown][] = []
-      yield* addPlugin(plugin, GitLabPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("gitlab", "duo-workflow-custom", {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("gitlab"), ModelV2.ID.make("duo-workflow-custom")),
+            api: { id: ModelV2.ID.make("duo-workflow-custom"), type: "aisdk", package: "test-provider" },
             request: {
               headers: {},
               body: { workflowRef: "ref", workflowDefinition: "definition" },
@@ -178,11 +235,14 @@ describe("GitLabPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: [string, unknown][] = []
-      yield* addPlugin(plugin, GitLabPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("gitlab", "duo-workflow-exact"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("gitlab"), ModelV2.ID.make("duo-workflow-exact")),
+            api: { id: ModelV2.ID.make("duo-workflow-exact"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: {
             workflowChat: (id: string, options: unknown) => {
               calls.push([id, options])
@@ -205,11 +265,13 @@ describe("GitLabPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: [string, unknown][] = []
-      yield* addPlugin(plugin, GitLabPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("gitlab", "duo-workflow-custom", {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("gitlab"), ModelV2.ID.make("duo-workflow-custom")),
+            api: { id: ModelV2.ID.make("duo-workflow-custom"), type: "aisdk", package: "test-provider" },
             request: {
               headers: {},
               body: { featureFlags: { request_flag: true } },
@@ -234,11 +296,13 @@ describe("GitLabPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: [string, unknown][] = []
-      yield* addPlugin(plugin, GitLabPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("gitlab", "claude", {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("gitlab"), ModelV2.ID.make("claude")),
+            api: { id: ModelV2.ID.make("claude"), type: "aisdk", package: "test-provider" },
             request: { headers: { h: "v" }, body: {} },
           }),
           sdk: {

packages/core/test/plugin/provider-google-vertex-anthropic.test.ts

@@ -1,10 +1,50 @@
+import type { LanguageModelV3 } from "@ai-sdk/provider"
 import { describe, expect } from "bun:test"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { GoogleVertexAnthropicPlugin, GoogleVertexPlugin } from "@opencode-ai/core/plugin/provider/google-vertex"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, fakeSelectorSdk, it, model, required, withEnv } from "./provider-helper"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* (definition: typeof GoogleVertexAnthropicPlugin | typeof GoogleVertexPlugin) {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: definition.id, effect: definition.effect(host) })
+})
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, effect: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    effect,
+    (previous) =>
+      Effect.sync(() => {
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        })
+      }),
+  )
+}
+
+function selector(calls: string[]) {
+  return (id: string) => {
+    calls.push(`languageModel:${id}`)
+    return { modelId: id, provider: "languageModel", specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+}
 
 describe("GoogleVertexAnthropicPlugin", () => {
   it.effect("resolves legacy project and location env on provider update", () =>
@@ -19,17 +59,19 @@ describe("GoogleVertexAnthropicPlugin", () => {
       },
       () =>
         Effect.gen(function* () {
-          const plugin = yield* PluginV2.Service
           const catalog = yield* Catalog.Service
-          yield* addPlugin(plugin, GoogleVertexAnthropicPlugin)
           yield* catalog.transform((catalog) =>
             catalog.provider.update(ProviderV2.ID.make("google-vertex-anthropic"), (provider) => {
               provider.api = { type: "aisdk", package: "@ai-sdk/google-vertex/anthropic" }
             }),
           )
-          const provider = required(yield* catalog.provider.get(ProviderV2.ID.make("google-vertex-anthropic")))
-          expect(provider.request.body.project).toBe("cloud-project")
-          expect(provider.request.body.location).toBe("cloud-location")
+          yield* addPlugin(GoogleVertexAnthropicPlugin)
+          expect(
+            (yield* catalog.provider.get(ProviderV2.ID.make("google-vertex-anthropic")))?.request.body.project,
+          ).toBe("cloud-project")
+          expect(
+            (yield* catalog.provider.get(ProviderV2.ID.make("google-vertex-anthropic")))?.request.body.location,
+          ).toBe("cloud-location")
         }),
     ),
   )
@@ -37,9 +79,7 @@ describe("GoogleVertexAnthropicPlugin", () => {
   it.effect("keeps configured project and location over env fallback", () =>
     withEnv({ GOOGLE_CLOUD_PROJECT: "env-project", GOOGLE_CLOUD_LOCATION: "env-location" }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
-        yield* addPlugin(plugin, GoogleVertexAnthropicPlugin)
         yield* catalog.transform((catalog) =>
           catalog.provider.update(ProviderV2.ID.make("google-vertex-anthropic"), (provider) => {
             provider.api = { type: "aisdk", package: "@ai-sdk/google-vertex/anthropic" }
@@ -47,9 +87,13 @@ describe("GoogleVertexAnthropicPlugin", () => {
             provider.request.body.location = "configured-location"
           }),
         )
-        const provider = required(yield* catalog.provider.get(ProviderV2.ID.make("google-vertex-anthropic")))
-        expect(provider.request.body.project).toBe("configured-project")
-        expect(provider.request.body.location).toBe("configured-location")
+        yield* addPlugin(GoogleVertexAnthropicPlugin)
+        expect((yield* catalog.provider.get(ProviderV2.ID.make("google-vertex-anthropic")))?.request.body.project).toBe(
+          "configured-project",
+        )
+        expect(
+          (yield* catalog.provider.get(ProviderV2.ID.make("google-vertex-anthropic")))?.request.body.location,
+        ).toBe("configured-location")
       }),
     ),
   )
@@ -67,11 +111,17 @@ describe("GoogleVertexAnthropicPlugin", () => {
       () =>
         Effect.gen(function* () {
           const plugin = yield* PluginV2.Service
-          yield* addPlugin(plugin, GoogleVertexAnthropicPlugin)
+          yield* addPlugin(GoogleVertexAnthropicPlugin)
           const result = yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("google-vertex-anthropic", "claude-sonnet-4-5"),
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(
+                  ProviderV2.ID.make("google-vertex-anthropic"),
+                  ModelV2.ID.make("claude-sonnet-4-5"),
+                ),
+                api: { id: ModelV2.ID.make("claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+              }),
               package: "@ai-sdk/google-vertex/anthropic",
               options: { name: "google-vertex-anthropic" },
             },
@@ -90,11 +140,17 @@ describe("GoogleVertexAnthropicPlugin", () => {
       () =>
         Effect.gen(function* () {
           const plugin = yield* PluginV2.Service
-          yield* addPlugin(plugin, GoogleVertexAnthropicPlugin)
+          yield* addPlugin(GoogleVertexAnthropicPlugin)
           const result = yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("google-vertex-anthropic", "claude-sonnet-4-5"),
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(
+                  ProviderV2.ID.make("google-vertex-anthropic"),
+                  ModelV2.ID.make("claude-sonnet-4-5"),
+                ),
+                api: { id: ModelV2.ID.make("claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+              }),
               package: "@ai-sdk/google-vertex/anthropic",
               options: { name: "google-vertex-anthropic" },
             },
@@ -110,11 +166,14 @@ describe("GoogleVertexAnthropicPlugin", () => {
   it.effect("creates SDKs for google-vertex Anthropic models with multi-region endpoints", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GoogleVertexAnthropicPlugin)
+      yield* addPlugin(GoogleVertexAnthropicPlugin)
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("google-vertex", "claude-sonnet-4-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("google-vertex"), ModelV2.ID.make("claude-sonnet-4-5")),
+            api: { id: ModelV2.ID.make("claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/google-vertex/anthropic",
           options: { name: "google-vertex", project: "project", location: "eu" },
         },
@@ -129,11 +188,14 @@ describe("GoogleVertexAnthropicPlugin", () => {
   it.effect("keeps configured baseURL for google-vertex Anthropic models", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GoogleVertexAnthropicPlugin)
+      yield* addPlugin(GoogleVertexAnthropicPlugin)
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("google-vertex", "claude-sonnet-4-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("google-vertex"), ModelV2.ID.make("claude-sonnet-4-5")),
+            api: { id: ModelV2.ID.make("claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/google-vertex/anthropic",
           options: { name: "google-vertex", project: "project", location: "eu", baseURL: "https://proxy.example/v1" },
         },
@@ -146,12 +208,15 @@ describe("GoogleVertexAnthropicPlugin", () => {
   it.effect("selects google-vertex Anthropic language models through V2 plugins", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GoogleVertexPlugin)
-      yield* addPlugin(plugin, GoogleVertexAnthropicPlugin)
+      yield* addPlugin(GoogleVertexPlugin)
+      yield* addPlugin(GoogleVertexAnthropicPlugin)
       const sdkResult = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("google-vertex", " claude-sonnet-4-5 "),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("google-vertex"), ModelV2.ID.make(" claude-sonnet-4-5 ")),
+            api: { id: ModelV2.ID.make(" claude-sonnet-4-5 "), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/google-vertex/anthropic",
           options: { name: "google-vertex", project: "project", location: "us" },
         },
@@ -160,7 +225,10 @@ describe("GoogleVertexAnthropicPlugin", () => {
       const languageResult = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("google-vertex", " claude-sonnet-4-5 "),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("google-vertex"), ModelV2.ID.make(" claude-sonnet-4-5 ")),
+            api: { id: ModelV2.ID.make(" claude-sonnet-4-5 "), type: "aisdk", package: "test-provider" },
+          }),
           sdk: sdkResult.sdk,
           options: {},
         },
@@ -178,12 +246,18 @@ describe("GoogleVertexAnthropicPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, GoogleVertexAnthropicPlugin)
+      yield* addPlugin(GoogleVertexAnthropicPlugin)
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("google-vertex-anthropic", " claude-sonnet-4-5 "),
-          sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(
+              ProviderV2.ID.make("google-vertex-anthropic"),
+              ModelV2.ID.make(" claude-sonnet-4-5 "),
+            ),
+            api: { id: ModelV2.ID.make(" claude-sonnet-4-5 "), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: { languageModel: selector(calls) },
           options: {},
         },
         {},
@@ -196,12 +270,15 @@ describe("GoogleVertexAnthropicPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, GoogleVertexAnthropicPlugin)
+      yield* addPlugin(GoogleVertexAnthropicPlugin)
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("google-vertex", "claude-sonnet-4-5"),
-          sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("google-vertex"), ModelV2.ID.make("claude-sonnet-4-5")),
+            api: { id: ModelV2.ID.make("claude-sonnet-4-5"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: { languageModel: selector(calls) },
           options: {},
         },
         {},

packages/core/test/plugin/provider-google-vertex.test.ts

@@ -1,13 +1,63 @@
 import { describe, expect, mock } from "bun:test"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { GoogleVertexPlugin } from "@opencode-ai/core/plugin/provider/google-vertex"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, fakeSelectorSdk, it, model, required, withEnv } from "./provider-helper"
+import type { LanguageModelV3 } from "@ai-sdk/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
 
 const vertexOptions: Record<string, any>[] = []
 const googleAuthOptions: Record<string, any>[] = []
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: GoogleVertexPlugin.id, effect: GoogleVertexPlugin.effect(host) })
+})
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, effect: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    effect,
+    (previous) =>
+      Effect.sync(() =>
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        }),
+      ),
+  )
+}
+
+function fakeSelectorSdk(calls: string[]) {
+  const make = (method: string) => (id: string) => {
+    calls.push(`${method}:${id}`)
+    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+  return {
+    responses: make("responses"),
+    messages: make("messages"),
+    chat: make("chat"),
+    languageModel: make("languageModel"),
+  }
+}
 
 void mock.module("@ai-sdk/google-vertex", () => ({
   createVertex: (options: Record<string, any>) => {
@@ -37,9 +87,7 @@ void mock.module("google-auth-library", () => ({
 describe("GoogleVertexPlugin", () => {
   it.effect("ignores OpenAI-compatible providers that are not Google Vertex", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, GoogleVertexPlugin)
       yield* catalog.transform((catalog) =>
         catalog.provider.update(ProviderV2.ID.opencode, (provider) => {
           provider.api = {
@@ -49,6 +97,7 @@ describe("GoogleVertexPlugin", () => {
           }
         }),
       )
+      yield* addPlugin()
 
       const provider = required(yield* catalog.provider.get(ProviderV2.ID.opencode))
       expect(provider.request.body).toEqual({})
@@ -67,9 +116,7 @@ describe("GoogleVertexPlugin", () => {
       },
       () =>
         Effect.gen(function* () {
-          const plugin = yield* PluginV2.Service
           const catalog = yield* Catalog.Service
-          yield* addPlugin(plugin, GoogleVertexPlugin)
           yield* catalog.transform((catalog) =>
             catalog.provider.update(ProviderV2.ID.make("google-vertex"), (provider) => {
               provider.api = {
@@ -79,6 +126,7 @@ describe("GoogleVertexPlugin", () => {
               }
             }),
           )
+          yield* addPlugin()
           const provider = required(yield* catalog.provider.get(ProviderV2.ID.make("google-vertex")))
           expect(provider.request.body.project).toBe("google-cloud-project")
           expect(provider.request.body.location).toBe("google-vertex-location")
@@ -107,7 +155,6 @@ describe("GoogleVertexPlugin", () => {
           vertexOptions.length = 0
           const plugin = yield* PluginV2.Service
           const catalog = yield* Catalog.Service
-          yield* addPlugin(plugin, GoogleVertexPlugin)
           yield* catalog.transform((catalog) =>
             catalog.provider.update(ProviderV2.ID.make("google-vertex"), (provider) => {
               provider.api = {
@@ -117,12 +164,18 @@ describe("GoogleVertexPlugin", () => {
               }
             }),
           )
+          yield* addPlugin()
           const provider = required(yield* catalog.provider.get(ProviderV2.ID.make("google-vertex")))
           yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("google-vertex", "gemini", {
-                api: { type: "aisdk", package: "@ai-sdk/google-vertex" },
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.make("google-vertex"), ModelV2.ID.make("gemini")),
+                api: {
+                  id: ModelV2.ID.make("gemini"),
+                  type: "aisdk",
+                  package: "@ai-sdk/google-vertex",
+                },
               }),
               package: "@ai-sdk/google-vertex",
               options: { name: "google-vertex" },
@@ -154,9 +207,7 @@ describe("GoogleVertexPlugin", () => {
       },
       () =>
         Effect.gen(function* () {
-          const plugin = yield* PluginV2.Service
           const catalog = yield* Catalog.Service
-          yield* addPlugin(plugin, GoogleVertexPlugin)
           yield* catalog.transform((catalog) =>
             catalog.provider.update(ProviderV2.ID.make("google-vertex"), (provider) => {
               provider.api = {
@@ -168,6 +219,7 @@ describe("GoogleVertexPlugin", () => {
               provider.request.body.location = "global"
             }),
           )
+          yield* addPlugin()
           const provider = required(yield* catalog.provider.get(ProviderV2.ID.make("google-vertex")))
           expect(provider.request.body.project).toBe("config-project")
           expect(provider.request.body.location).toBe("global")
@@ -182,9 +234,7 @@ describe("GoogleVertexPlugin", () => {
 
   it.effect("keeps OpenAI-compatible Vertex endpoint templates regional for eu", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, GoogleVertexPlugin)
       yield* catalog.transform((catalog) =>
         catalog.provider.update(ProviderV2.ID.make("google-vertex"), (provider) => {
           provider.api = {
@@ -196,6 +246,7 @@ describe("GoogleVertexPlugin", () => {
           provider.request.body.location = "eu"
         }),
       )
+      yield* addPlugin()
       const provider = required(yield* catalog.provider.get(ProviderV2.ID.make("google-vertex")))
       expect(provider.api).toEqual({
         type: "aisdk",
@@ -217,15 +268,14 @@ describe("GoogleVertexPlugin", () => {
       },
       () =>
         Effect.gen(function* () {
-          const plugin = yield* PluginV2.Service
           const catalog = yield* Catalog.Service
-          yield* addPlugin(plugin, GoogleVertexPlugin)
           yield* catalog.transform((catalog) =>
             catalog.provider.update(ProviderV2.ID.make("google-vertex"), (provider) => {
               provider.api = { type: "aisdk", package: "@ai-sdk/google-vertex" }
               provider.request.body.project = "config-project"
             }),
           )
+          yield* addPlugin()
           const provider = required(yield* catalog.provider.get(ProviderV2.ID.make("google-vertex")))
           expect(provider.request.body.project).toBe("config-project")
           expect(provider.request.body.location).toBe("us-central1")
@@ -243,12 +293,17 @@ describe("GoogleVertexPlugin", () => {
         Effect.gen(function* () {
           vertexOptions.length = 0
           const plugin = yield* PluginV2.Service
-          yield* addPlugin(plugin, GoogleVertexPlugin)
+          yield* addPlugin()
           yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("google-vertex", "gemini", {
-                api: { type: "aisdk", package: "@ai-sdk/google-vertex" },
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.make("google-vertex"), ModelV2.ID.make("gemini")),
+                api: {
+                  id: ModelV2.ID.make("gemini"),
+                  type: "aisdk",
+                  package: "@ai-sdk/google-vertex",
+                },
               }),
               package: "@ai-sdk/google-vertex",
               options: { name: "google-vertex" },
@@ -268,21 +323,17 @@ describe("GoogleVertexPlugin", () => {
       googleAuthOptions.length = 0
       const fetchCalls: { input: Parameters<typeof fetch>[0]; init?: RequestInit }[] = []
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GoogleVertexPlugin)
-      yield* plugin.add({
-        id: PluginV2.ID.make("capture-openai-compatible"),
-        effect: Effect.succeed({
-          "aisdk.sdk": (evt) =>
-            Effect.promise(async () => {
-              if (evt.model.providerID !== "google-vertex") return
-              if (evt.package !== "@ai-sdk/openai-compatible") return
-              expect(typeof evt.options.fetch).toBe("function")
-              await evt.options.fetch("https://vertex.example", {
-                headers: { "x-test": "1" },
-              })
-            }),
+      yield* addPlugin()
+      yield* plugin.hook("aisdk.sdk", (evt) =>
+        Effect.promise(async () => {
+          if (evt.model.providerID !== "google-vertex") return
+          if (evt.package !== "@ai-sdk/openai-compatible") return
+          expect(typeof evt.options.fetch).toBe("function")
+          await evt.options.fetch("https://vertex.example", {
+            headers: { "x-test": "1" },
+          })
         }),
-      })
+      )
       const originalFetch = fetch
       ;(globalThis as typeof globalThis & { fetch: typeof fetch }).fetch = (async (
         input: Parameters<typeof fetch>[0],
@@ -297,8 +348,13 @@ describe("GoogleVertexPlugin", () => {
           plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("google-vertex", "gemini", {
-                api: { type: "aisdk", package: "@ai-sdk/openai-compatible" },
+              model: new ModelV2.Info({
+                ...ModelV2.Info.empty(ProviderV2.ID.make("google-vertex"), ModelV2.ID.make("gemini")),
+                api: {
+                  id: ModelV2.ID.make("gemini"),
+                  type: "aisdk",
+                  package: "@ai-sdk/openai-compatible",
+                },
               }),
               package: "@ai-sdk/openai-compatible",
               options: { name: "google-vertex" },
@@ -322,11 +378,14 @@ describe("GoogleVertexPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, GoogleVertexPlugin)
+      yield* addPlugin()
       yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("google-vertex", " gemini-2.5-pro "),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("google-vertex"), ModelV2.ID.make(" gemini-2.5-pro ")),
+            api: { id: ModelV2.ID.make(" gemini-2.5-pro "), type: "aisdk", package: "test-provider" },
+          }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: {},
         },

packages/core/test/plugin/provider-google.test.ts

@@ -1,26 +1,33 @@
 import { describe, expect } from "bun:test"
-import { Effect, Layer } from "effect"
-import { AISDK } from "@opencode-ai/core/aisdk"
-import { EventV2 } from "@opencode-ai/core/event"
+import { Effect } from "effect"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { GooglePlugin } from "@opencode-ai/core/plugin/provider/google"
+import { ProviderV2 } from "@opencode-ai/core/provider"
 import { testEffect } from "../lib/effect"
-import { addPlugin, it, model } from "./provider-helper"
+import { PluginTestLayer } from "./fixture"
 
-const itWithAISDK = testEffect(
-  AISDK.layer.pipe(Layer.provideMerge(PluginV2.locationLayer.pipe(Layer.provide(EventV2.defaultLayer)))),
-)
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: GooglePlugin.id, effect: GooglePlugin.effect(host) })
+})
 
 describe("GooglePlugin", () => {
   it.effect("creates a Google Generative AI SDK for @ai-sdk/google using the provider ID as SDK name", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GooglePlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-google", "gemini"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-google"), ModelV2.ID.make("gemini")),
+            api: { id: ModelV2.ID.make("gemini"), type: "aisdk", package: "@ai-sdk/google" },
+          }),
           package: "@ai-sdk/google",
           options: { name: "custom-google", apiKey: "test" },
         },
@@ -34,34 +41,49 @@ describe("GooglePlugin", () => {
   it.effect("ignores non-Google SDK packages", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GooglePlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("google", "gemini"), package: "@ai-sdk/google-vertex", options: { name: "google" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("google"), ModelV2.ID.make("gemini")),
+            api: { id: ModelV2.ID.make("gemini"), type: "aisdk", package: "@ai-sdk/google" },
+          }),
+          package: "@ai-sdk/google-vertex",
+          options: { name: "google" },
+        },
         {},
       )
       expect(result.sdk).toBeUndefined()
     }),
   )
 
-  itWithAISDK.effect("uses default languageModel loading with provider ID parity", () =>
+  it.effect("uses default languageModel loading with provider ID parity", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      const aisdk = yield* AISDK.Service
-      yield* addPlugin(plugin, GooglePlugin)
-      const language = yield* aisdk.language(
-        model("custom-google", "alias", {
-          api: {
-            id: ModelV2.ID.make("gemini-api"),
-            type: "aisdk",
-            package: "@ai-sdk/google",
-          },
-          request: {
-            headers: {},
-            body: { apiKey: "test" },
-          },
-        }),
+      yield* addPlugin()
+      const sdkEvent = yield* plugin.trigger(
+        "aisdk.sdk",
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-google"), ModelV2.ID.make("alias")),
+            api: { id: ModelV2.ID.make("gemini-api"), type: "aisdk", package: "@ai-sdk/google" },
+          }),
+          package: "@ai-sdk/google",
+          options: { name: "custom-google", apiKey: "test" },
+        },
+        {},
       )
+      const result = yield* plugin.trigger(
+        "aisdk.language",
+        {
+          model: sdkEvent.model,
+          sdk: sdkEvent.sdk,
+          options: sdkEvent.options,
+        },
+        {},
+      )
+      const language = result.language ?? result.sdk.languageModel(result.model.api.id)
       expect(language.modelId).toBe("gemini-api")
       expect(language.provider).toBe("custom-google")
     }),

packages/core/test/plugin/provider-groq.test.ts

@@ -1,26 +1,37 @@
 import { describe, expect } from "bun:test"
 import { createGroq } from "@ai-sdk/groq"
-import { Effect, Layer } from "effect"
-import { AISDK } from "@opencode-ai/core/aisdk"
-import { EventV2 } from "@opencode-ai/core/event"
+import { Effect } from "effect"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { GroqPlugin } from "@opencode-ai/core/plugin/provider/groq"
-import { addPlugin, it, model } from "./provider-helper"
+import { ProviderV2 } from "@opencode-ai/core/provider"
 import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
 
-const aisdkIt = testEffect(
-  AISDK.layer.pipe(Layer.provideMerge(PluginV2.locationLayer.pipe(Layer.provide(EventV2.defaultLayer)))),
-)
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: GroqPlugin.id, effect: GroqPlugin.effect(host) })
+})
 
 describe("GroqPlugin", () => {
   it.effect("creates a Groq SDK for @ai-sdk/groq", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GroqPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("groq", "llama"), package: "@ai-sdk/groq", options: { name: "groq" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("groq"), ModelV2.ID.make("llama")),
+            api: { id: ModelV2.ID.make("llama"), type: "aisdk", package: "@ai-sdk/groq" },
+          }),
+          package: "@ai-sdk/groq",
+          options: { name: "groq" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -30,10 +41,17 @@ describe("GroqPlugin", () => {
   it.effect("ignores non-Groq SDK packages", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GroqPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("groq", "llama"), package: "@ai-sdk/openai-compatible", options: { name: "groq" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("groq"), ModelV2.ID.make("llama")),
+            api: { id: ModelV2.ID.make("llama"), type: "aisdk", package: "@ai-sdk/groq" },
+          }),
+          package: "@ai-sdk/openai-compatible",
+          options: { name: "groq" },
+        },
         {},
       )
       expect(result.sdk).toBeUndefined()
@@ -43,10 +61,17 @@ describe("GroqPlugin", () => {
   it.effect("only matches the bundled @ai-sdk/groq package exactly", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GroqPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("groq", "llama"), package: "@ai-sdk/groq/compat", options: { name: "groq" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("groq"), ModelV2.ID.make("llama")),
+            api: { id: ModelV2.ID.make("llama"), type: "aisdk", package: "@ai-sdk/groq" },
+          }),
+          package: "@ai-sdk/groq/compat",
+          options: { name: "groq" },
+        },
         {},
       )
       expect(result.sdk).toBeUndefined()
@@ -56,11 +81,14 @@ describe("GroqPlugin", () => {
   it.effect("matches the old bundled Groq SDK provider naming", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, GroqPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-groq", "llama"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-groq"), ModelV2.ID.make("llama")),
+            api: { id: ModelV2.ID.make("llama"), type: "aisdk", package: "@ai-sdk/groq" },
+          }),
           package: "@ai-sdk/groq",
           options: { name: "custom-groq", apiKey: "test" },
         },
@@ -75,26 +103,32 @@ describe("GroqPlugin", () => {
     }),
   )
 
-  aisdkIt.effect("uses the default languageModel(api.id) behavior", () =>
+  it.effect("uses the default languageModel(api.id) behavior", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      const aisdk = yield* AISDK.Service
-      yield* addPlugin(plugin, GroqPlugin)
-      const result = yield* aisdk.language(
-        model("groq", "alias", {
-          api: {
-            id: ModelV2.ID.make("llama-api"),
-            type: "aisdk",
-            package: "@ai-sdk/groq",
-          },
-          request: {
-            headers: {},
-            body: { apiKey: "test" },
-          },
-        }),
+      yield* addPlugin()
+      const sdk = createGroq({ name: "groq", apiKey: "test" } as Parameters<typeof createGroq>[0] & {
+        name: string
+      })
+      const result = yield* plugin.trigger(
+        "aisdk.language",
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("groq"), ModelV2.ID.make("alias")),
+            api: {
+              id: ModelV2.ID.make("llama-api"),
+              type: "aisdk",
+              package: "@ai-sdk/groq",
+            },
+          }),
+          sdk,
+          options: { name: "groq", apiKey: "test" },
+        },
+        {},
       )
-      expect(result.modelId).toBe("llama-api")
-      expect(result.provider).toBe("groq.chat")
+      const language = result.language ?? sdk.languageModel(result.model.api.id)
+      expect(language.modelId).toBe("llama-api")
+      expect(language.provider).toBe("groq.chat")
     }),
   )
 })

packages/core/test/plugin/provider-helper.ts

@@ -1,189 +0,0 @@
-import { Npm } from "@opencode-ai/core/npm"
-import type { Plugin } from "@opencode-ai/plugin/v2/effect"
-import type { LanguageModelV3 } from "@ai-sdk/provider"
-import { expect } from "bun:test"
-import { Effect, Layer, Option } from "effect"
-import { Catalog } from "@opencode-ai/core/catalog"
-import { Integration } from "@opencode-ai/core/integration"
-import { Credential } from "@opencode-ai/core/credential"
-import { EventV2 } from "@opencode-ai/core/event"
-import { Location } from "@opencode-ai/core/location"
-import { ModelV2 } from "@opencode-ai/core/model"
-import { PluginV2 } from "@opencode-ai/core/plugin"
-import { ProviderV2 } from "@opencode-ai/core/provider"
-import { AbsolutePath } from "@opencode-ai/core/schema"
-import { location } from "../fixture/location"
-import { testEffect } from "../lib/effect"
-import { aisdkHost, catalogHost, host, integrationHost } from "./host"
-
-export const fixtureProvider = new URL("./fixtures/provider-factory.ts", import.meta.url).href
-
-export function required<T>(value: T | undefined): T {
-  if (value === undefined) throw new Error("Expected value")
-  return value
-}
-
-const locationLayer = Layer.succeed(
-  Location.Service,
-  Location.Service.of(location({ directory: AbsolutePath.make("test") })),
-)
-
-export const npmLayer = Layer.succeed(
-  Npm.Service,
-  Npm.Service.of({
-    add: () => Effect.succeed({ directory: "", entrypoint: undefined }),
-    install: () => Effect.void,
-    which: () => Effect.succeed(undefined),
-  }),
-)
-
-export const catalogLayer = Layer.succeed(
-  Catalog.Service,
-  Catalog.Service.of({
-    transform: (_transform) => Effect.die("unexpected catalog.transform"),
-    rebuild: () => Effect.die("unexpected catalog.rebuild"),
-    provider: {
-      get: () => Effect.die("unexpected provider.get"),
-      all: () => Effect.succeed([]),
-      available: () => Effect.succeed([]),
-    },
-    model: {
-      get: () => Effect.die("unexpected model.get"),
-      all: () => Effect.succeed([]),
-      available: () => Effect.succeed([]),
-      default: () => Effect.succeed(undefined),
-      small: () => Effect.succeed(undefined),
-    },
-  }),
-)
-
-const integrations = Integration.locationLayer.pipe(
-  Layer.provide(EventV2.defaultLayer),
-  Layer.provide(
-    Layer.mock(Credential.Service)({
-      create: () => Effect.die("unexpected credential creation"),
-      all: () => Effect.succeed([]),
-      list: () => Effect.succeed([]),
-    }),
-  ),
-)
-
-export const it = testEffect(
-  Catalog.locationLayer.pipe(
-    Layer.provideMerge(integrations),
-    Layer.provideMerge(
-      Layer.mock(Credential.Service)({
-        all: () => Effect.succeed([]),
-      }),
-    ),
-    Layer.provideMerge(EventV2.defaultLayer),
-    Layer.provideMerge(locationLayer),
-    Layer.provideMerge(npmLayer),
-    Layer.provideMerge(PluginV2.locationLayer.pipe(Layer.provide(EventV2.defaultLayer))),
-  ),
-)
-
-export function addPlugin(plugin: PluginV2.Interface, definition: Plugin<any>) {
-  return Effect.gen(function* () {
-    const catalog = yield* Effect.serviceOption(Catalog.Service)
-    const integration = yield* Effect.serviceOption(Integration.Service)
-    const npm = yield* Effect.serviceOption(Npm.Service)
-    const effect =
-      typeof definition.effect === "function"
-          ? definition.effect(
-            host({
-              aisdk: aisdkHost(plugin),
-              ...(Option.isSome(catalog) ? { catalog: catalogHost(catalog.value) } : {}),
-              ...(Option.isSome(integration) ? { integration: integrationHost(integration.value) } : {}),
-              ...(Option.isSome(npm) ? { npm: npm.value } : {}),
-            }),
-          )
-        : definition.effect
-    yield* plugin.add({ id: definition.id, effect })
-  })
-}
-
-type ProviderInput = Partial<Omit<ProviderV2.Info, "api" | "request">> & {
-  api?: ProviderV2.Api
-  request?: ProviderV2.Request
-}
-
-type ModelInput = Partial<Omit<ModelV2.Info, "api" | "request">> & {
-  api?: (ProviderV2.Api & { id?: ModelV2.ID }) | { id: ModelV2.ID }
-  request?: ModelV2.Info["request"]
-}
-
-export function provider(providerID: string, options?: ProviderInput) {
-  return new ProviderV2.Info({
-    ...ProviderV2.Info.empty(ProviderV2.ID.make(providerID)),
-    api: options?.api ?? {
-      type: "aisdk",
-      package: "test-provider",
-    },
-    ...options,
-    request: {
-      headers: {},
-      body: {},
-      ...options?.request,
-    },
-  })
-}
-
-export function model(providerID: string, modelID: string, options?: ModelInput) {
-  return new ModelV2.Info({
-    ...ModelV2.Info.empty(ProviderV2.ID.make(providerID), ModelV2.ID.make(modelID)),
-    ...options,
-    api:
-      options?.api && "type" in options.api
-        ? { id: ModelV2.ID.make(modelID), ...options.api }
-        : {
-            id: ModelV2.ID.make(modelID),
-            ...options?.api,
-            type: "aisdk",
-            package: "test-provider",
-          },
-    request: {
-      headers: {},
-      body: {},
-      ...options?.request,
-    },
-  })
-}
-
-export function withEnv<A, E, R>(vars: Record<string, string | undefined>, fx: () => Effect.Effect<A, E, R>) {
-  return Effect.acquireUseRelease(
-    Effect.sync(() => {
-      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
-      for (const [key, value] of Object.entries(vars)) {
-        if (value === undefined) delete process.env[key]
-        else process.env[key] = value
-      }
-      return previous
-    }),
-    () => fx(),
-    (previous) =>
-      Effect.sync(() => {
-        for (const [key, value] of Object.entries(previous)) {
-          if (value === undefined) delete process.env[key]
-          else process.env[key] = value
-        }
-      }),
-  )
-}
-
-export function fakeSelectorSdk(calls: string[]) {
-  const make = (method: string) => (id: string) => {
-    calls.push(`${method}:${id}`)
-    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
-  }
-  return {
-    responses: make("responses"),
-    messages: make("messages"),
-    chat: make("chat"),
-    languageModel: make("languageModel"),
-  }
-}
-
-export function expectPluginRegistered(ids: string[], id: string) {
-  expect(ids).toContain(PluginV2.ID.make(id))
-}

packages/core/test/plugin/provider-kilo.test.ts

@@ -2,96 +2,98 @@ import { describe, expect } from "bun:test"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { ProviderPlugins } from "@opencode-ai/core/plugin/provider"
 import { KiloPlugin } from "@opencode-ai/core/plugin/provider/kilo"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, expectPluginRegistered, it, provider, required } from "./provider-helper"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: KiloPlugin.id, effect: KiloPlugin.effect(host) })
+})
 
 describe("KiloPlugin", () => {
   it.effect("is registered so legacy referer headers can be applied", () =>
-    Effect.sync(() =>
-      expectPluginRegistered(
-        ProviderPlugins.map((item) => item.id),
-        "kilo",
-      ),
-    ),
+    Effect.sync(() => expect(ProviderPlugins.map((item) => item.id)).toContain(PluginV2.ID.make("kilo"))),
   )
 
   it.effect("applies legacy referer headers only to kilo", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, KiloPlugin)
       yield* catalog.transform((catalog) => {
-        const kilo = provider("kilo", {
-          api: { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://api.kilo.ai/api/gateway" },
-          request: { headers: { Existing: "value" }, body: {} },
+        catalog.provider.update(ProviderV2.ID.make("kilo"), (provider) => {
+          provider.api = {
+            type: "aisdk",
+            package: "@ai-sdk/openai-compatible",
+            url: "https://api.kilo.ai/api/gateway",
+          }
+          provider.request = { headers: { Existing: "value" }, body: {} }
         })
-        catalog.provider.update(kilo.id, (draft) => {
-          draft.api = kilo.api
-          draft.request = kilo.request
-        })
-        catalog.provider.update(provider("openrouter").id, () => {})
+        catalog.provider.update(ProviderV2.ID.openrouter, () => {})
       })
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("kilo"))).request.headers).toEqual({
+      yield* addPlugin()
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("kilo")))?.request.headers).toEqual({
         Existing: "value",
         "HTTP-Referer": "https://opencode.ai/",
         "X-Title": "opencode",
       })
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.openrouter)).request.headers).toEqual({})
+      expect((yield* catalog.provider.get(ProviderV2.ID.openrouter))?.request.headers).toEqual({})
     }),
   )
 
   it.effect("uses the exact legacy Kilo header casing and set", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, KiloPlugin)
       yield* catalog.transform((catalog) => {
-        const item = provider("kilo", {
-          api: { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://api.kilo.ai/api/gateway" },
-        })
-        catalog.provider.update(item.id, (draft) => {
-          draft.api = item.api
+        catalog.provider.update(ProviderV2.ID.make("kilo"), (provider) => {
+          provider.api = {
+            type: "aisdk",
+            package: "@ai-sdk/openai-compatible",
+            url: "https://api.kilo.ai/api/gateway",
+          }
         })
       })
+      yield* addPlugin()
 
-      const result = required(yield* catalog.provider.get(ProviderV2.ID.make("kilo")))
-      expect(result.request.headers).toEqual({
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("kilo")))?.request.headers).toEqual({
         "HTTP-Referer": "https://opencode.ai/",
         "X-Title": "opencode",
       })
-      expect(result.request.headers).not.toHaveProperty("http-referer")
-      expect(result.request.headers).not.toHaveProperty("x-title")
-      expect(result.request.headers).not.toHaveProperty("X-Source")
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("kilo")))?.request.headers).not.toHaveProperty(
+        "http-referer",
+      )
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("kilo")))?.request.headers).not.toHaveProperty("x-title")
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("kilo")))?.request.headers).not.toHaveProperty("X-Source")
     }),
   )
 
   it.effect("uses the legacy provider-id guard instead of endpoint package matching", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, KiloPlugin)
       yield* catalog.transform((catalog) => {
-        const kilo = provider("kilo", {
-          api: { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://api.kilo.ai/api/gateway" },
+        catalog.provider.update(ProviderV2.ID.make("kilo"), (provider) => {
+          provider.api = {
+            type: "aisdk",
+            package: "@ai-sdk/openai-compatible",
+            url: "https://api.kilo.ai/api/gateway",
+          }
         })
-        catalog.provider.update(kilo.id, (draft) => {
-          draft.api = kilo.api
-        })
-        const custom = provider("custom-kilo", {
-          api: { type: "aisdk", package: "kilo" },
-        })
-        catalog.provider.update(custom.id, (draft) => {
-          draft.api = custom.api
+        catalog.provider.update(ProviderV2.ID.make("custom-kilo"), (provider) => {
+          provider.api = { type: "aisdk", package: "kilo" }
         })
       })
+      yield* addPlugin()
 
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("kilo"))).request.headers).toEqual({
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("kilo")))?.request.headers).toEqual({
         "HTTP-Referer": "https://opencode.ai/",
         "X-Title": "opencode",
       })
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("custom-kilo"))).request.headers).toEqual({})
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("custom-kilo")))?.request.headers).toEqual({})
     }),
   )
 })

packages/core/test/plugin/provider-llmgateway.test.ts

@@ -3,36 +3,28 @@ import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
 import { Integration } from "@opencode-ai/core/integration"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { ProviderPlugins } from "@opencode-ai/core/plugin/provider"
 import { LLMGatewayPlugin } from "@opencode-ai/core/plugin/provider/llmgateway"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { expectPluginRegistered, it, provider, required } from "./provider-helper"
-import { catalogHost, host, integrationHost } from "./host"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: LLMGatewayPlugin.id, effect: LLMGatewayPlugin.effect(host) })
+})
 
 describe("LLMGatewayPlugin", () => {
-  const add = Effect.fnUntraced(function* (plugin: PluginV2.Interface) {
-    const integrations = yield* Integration.Service
-    const catalog = yield* Catalog.Service
-    yield* plugin.add({
-      ...LLMGatewayPlugin,
-      effect: LLMGatewayPlugin.effect(
-        host({ catalog: catalogHost(catalog), integration: integrationHost(integrations) }),
-      ),
-    })
-  })
-
   it.effect("is registered so legacy referer headers can be applied", () =>
-    Effect.sync(() =>
-      expectPluginRegistered(
-        ProviderPlugins.map((item) => item.id),
-        "llmgateway",
-      ),
-    ),
+    Effect.sync(() => expect(ProviderPlugins.map((item) => item.id)).toContain(PluginV2.ID.make("llmgateway"))),
   )
 
   it.effect("applies legacy referer headers only to enabled llmgateway", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
       const integrations = yield* Integration.Service
       yield* integrations.transform((editor) => {
@@ -40,43 +32,48 @@ describe("LLMGatewayPlugin", () => {
         editor.update(Integration.ID.make("openrouter"), () => {})
       })
       yield* catalog.transform((catalog) => {
-        const llmgateway = provider("llmgateway", {
-          api: { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://api.llmgateway.io/v1" },
-          request: { headers: { Existing: "value" }, body: {} },
-        })
-        catalog.provider.update(llmgateway.id, (draft) => {
-          draft.api = llmgateway.api
-          draft.request = llmgateway.request
+        catalog.provider.update(ProviderV2.ID.make("llmgateway"), (provider) => {
+          provider.api = {
+            type: "aisdk",
+            package: "@ai-sdk/openai-compatible",
+            url: "https://api.llmgateway.io/v1",
+          }
+          provider.request = { headers: { Existing: "value" }, body: {} }
         })
         catalog.provider.update(ProviderV2.ID.openrouter, () => {})
       })
-      yield* add(plugin)
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("llmgateway"))).request.headers).toEqual({
+      yield* addPlugin()
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("llmgateway")))?.request.headers).toEqual({
         Existing: "value",
         "HTTP-Referer": "https://opencode.ai/",
         "X-Title": "opencode",
         "X-Source": "opencode",
       })
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.openrouter)).request.headers).toEqual({})
+      expect((yield* catalog.provider.get(ProviderV2.ID.openrouter))?.request.headers).toEqual({})
     }),
   )
 
   it.effect("does not apply legacy headers to a disabled llmgateway provider", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* add(plugin)
+      const integrations = yield* Integration.Service
+      yield* integrations.transform((editor) => {
+        editor.update(Integration.ID.make("llmgateway"), () => {})
+      })
       yield* catalog.transform((catalog) => {
-        const item = provider("llmgateway", {
-          api: { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://api.llmgateway.io/v1" },
-        })
-        catalog.provider.update(item.id, (draft) => {
-          draft.api = item.api
+        catalog.provider.update(ProviderV2.ID.make("llmgateway"), (provider) => {
+          provider.disabled = true
+          provider.api = {
+            type: "aisdk",
+            package: "@ai-sdk/openai-compatible",
+            url: "https://api.llmgateway.io/v1",
+          }
         })
       })
+      yield* addPlugin()
 
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("llmgateway"))).disabled).toBeUndefined()
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("llmgateway"))).request.headers).toEqual({})
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("llmgateway")))?.disabled).toBe(true)
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("llmgateway")))?.request.headers).toEqual({})
     }),
   )
 })

packages/core/test/plugin/provider-mistral.test.ts

@@ -1,18 +1,37 @@
+import type { LanguageModelV3 } from "@ai-sdk/provider"
 import { describe, expect } from "bun:test"
 import { Effect } from "effect"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { MistralPlugin } from "@opencode-ai/core/plugin/provider/mistral"
-import { addPlugin, fakeSelectorSdk, it, model } from "./provider-helper"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: MistralPlugin.id, effect: MistralPlugin.effect(host) })
+})
 
 describe("MistralPlugin", () => {
   it.effect("creates a Mistral SDK for @ai-sdk/mistral", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, MistralPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("mistral", "mistral-large"), package: "@ai-sdk/mistral", options: { name: "mistral" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("mistral"), ModelV2.ID.make("mistral-large")),
+            api: { id: ModelV2.ID.make("mistral-large"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/mistral",
+          options: { name: "mistral" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -22,11 +41,14 @@ describe("MistralPlugin", () => {
   it.effect("ignores non-Mistral SDK packages", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, MistralPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("mistral", "mistral-large"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("mistral"), ModelV2.ID.make("mistral-large")),
+            api: { id: ModelV2.ID.make("mistral-large"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/openai-compatible",
           options: { name: "mistral" },
         },
@@ -40,19 +62,22 @@ describe("MistralPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const providers: string[] = []
-      yield* addPlugin(plugin, MistralPlugin)
-      yield* plugin.add({
-        id: PluginV2.ID.make("mistral-sdk-inspector"),
-        effect: Effect.succeed({
-          "aisdk.sdk": (evt) =>
-            Effect.sync(() => {
-              providers.push(evt.sdk.languageModel("mistral-large").provider)
-            }),
+      yield* addPlugin()
+      yield* plugin.hook("aisdk.sdk", (event) =>
+        Effect.sync(() => {
+          providers.push(event.sdk.languageModel("mistral-large").provider)
         }),
-      })
+      )
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("mistral", "mistral-large"), package: "@ai-sdk/mistral", options: { name: "mistral" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("mistral"), ModelV2.ID.make("mistral-large")),
+            api: { id: ModelV2.ID.make("mistral-large"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/mistral",
+          options: { name: "mistral" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -64,20 +89,19 @@ describe("MistralPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const providers: string[] = []
-      yield* addPlugin(plugin, MistralPlugin)
-      yield* plugin.add({
-        id: PluginV2.ID.make("mistral-sdk-inspector"),
-        effect: Effect.succeed({
-          "aisdk.sdk": (evt) =>
-            Effect.sync(() => {
-              providers.push(evt.sdk.languageModel("mistral-large").provider)
-            }),
+      yield* addPlugin()
+      yield* plugin.hook("aisdk.sdk", (event) =>
+        Effect.sync(() => {
+          providers.push(event.sdk.languageModel("mistral-large").provider)
         }),
-      })
+      )
       yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-mistral", "mistral-large"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-mistral"), ModelV2.ID.make("mistral-large")),
+            api: { id: ModelV2.ID.make("mistral-large"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/mistral",
           options: { name: "custom-mistral" },
         },
@@ -91,11 +115,23 @@ describe("MistralPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      const sdk = fakeSelectorSdk(calls)
-      yield* addPlugin(plugin, MistralPlugin)
+      const sdk = {
+        languageModel: (id: string) => {
+          calls.push(`languageModel:${id}`)
+          return { modelId: id, provider: "languageModel", specificationVersion: "v3" } as unknown as LanguageModelV3
+        },
+      }
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.language",
-        { model: model("mistral", "alias", { api: { id: ModelV2.ID.make("mistral-large") } }), sdk, options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("mistral"), ModelV2.ID.make("alias")),
+            api: { id: ModelV2.ID.make("mistral-large"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk,
+          options: {},
+        },
         {},
       )
       const language = result.language ?? sdk.languageModel(result.model.api.id)

packages/core/test/plugin/provider-nvidia.test.ts

@@ -2,64 +2,66 @@ import { describe, expect } from "bun:test"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { ProviderPlugins } from "@opencode-ai/core/plugin/provider"
 import { NvidiaPlugin } from "@opencode-ai/core/plugin/provider/nvidia"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, expectPluginRegistered, it, provider, required } from "./provider-helper"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: NvidiaPlugin.id, effect: NvidiaPlugin.effect(host) })
+})
 
 describe("NvidiaPlugin", () => {
   it.effect("is registered so legacy referer headers can be applied", () =>
-    Effect.sync(() =>
-      expectPluginRegistered(
-        ProviderPlugins.map((item) => item.id),
-        "nvidia",
-      ),
-    ),
+    Effect.sync(() => expect(ProviderPlugins.map((item) => item.id)).toContain(PluginV2.ID.make("nvidia"))),
   )
 
   it.effect("applies NVIDIA tracking headers only to nvidia", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, NvidiaPlugin)
       yield* catalog.transform((catalog) => {
-        const nvidia = provider("nvidia", {
-          api: { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://integrate.api.nvidia.com/v1" },
-          request: { headers: { Existing: "value" }, body: {} },
+        catalog.provider.update(ProviderV2.ID.make("nvidia"), (provider) => {
+          provider.api = {
+            type: "aisdk",
+            package: "@ai-sdk/openai-compatible",
+            url: "https://integrate.api.nvidia.com/v1",
+          }
+          provider.request = { headers: { Existing: "value" }, body: {} }
         })
-        catalog.provider.update(nvidia.id, (draft) => {
-          draft.api = nvidia.api
-          draft.request = nvidia.request
-        })
-        catalog.provider.update(provider("openrouter").id, () => {})
+        catalog.provider.update(ProviderV2.ID.openrouter, () => {})
       })
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("nvidia"))).request.headers).toEqual({
+      yield* addPlugin()
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("nvidia")))?.request.headers).toEqual({
         Existing: "value",
         "HTTP-Referer": "https://opencode.ai/",
         "X-Title": "opencode",
         "X-BILLING-INVOKE-ORIGIN": "OpenCode",
       })
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.openrouter)).request.headers).toEqual({})
+      expect((yield* catalog.provider.get(ProviderV2.ID.openrouter))?.request.headers).toEqual({})
     }),
   )
 
   it.effect("adds billing origin for custom NVIDIA endpoints", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, NvidiaPlugin)
       yield* catalog.transform((catalog) => {
-        const item = provider("nvidia", {
-          api: { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://integrate.api.nvidia.com/v1" },
-          request: { headers: {}, body: {} },
-        })
-        catalog.provider.update(item.id, (draft) => {
-          draft.api = item.api
-          draft.request = item.request
+        catalog.provider.update(ProviderV2.ID.make("nvidia"), (provider) => {
+          provider.api = {
+            type: "aisdk",
+            package: "@ai-sdk/openai-compatible",
+            url: "https://integrate.api.nvidia.com/v1",
+          }
         })
       })
+      yield* addPlugin()
 
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("nvidia"))).request.headers).toEqual({
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("nvidia")))?.request.headers).toEqual({
         "HTTP-Referer": "https://opencode.ai/",
         "X-Title": "opencode",
         "X-BILLING-INVOKE-ORIGIN": "OpenCode",
@@ -69,24 +71,23 @@ describe("NvidiaPlugin", () => {
 
   it.effect("preserves an explicit NVIDIA billing origin header", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, NvidiaPlugin)
       yield* catalog.transform((catalog) => {
-        const item = provider("nvidia", {
-          api: { type: "aisdk", package: "@ai-sdk/openai-compatible", url: "https://integrate.api.nvidia.com/v1" },
-          request: {
+        catalog.provider.update(ProviderV2.ID.make("nvidia"), (provider) => {
+          provider.api = {
+            type: "aisdk",
+            package: "@ai-sdk/openai-compatible",
+            url: "https://integrate.api.nvidia.com/v1",
+          }
+          provider.request = {
             headers: { "X-BILLING-INVOKE-ORIGIN": "CustomOrigin" },
             body: { baseURL: "https://integrate.api.nvidia.com/v1" },
-          },
-        })
-        catalog.provider.update(item.id, (draft) => {
-          draft.api = item.api
-          draft.request = item.request
+          }
         })
       })
+      yield* addPlugin()
 
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("nvidia"))).request.headers).toEqual({
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("nvidia")))?.request.headers).toEqual({
         "HTTP-Referer": "https://opencode.ai/",
         "X-Title": "opencode",
         "X-BILLING-INVOKE-ORIGIN": "CustomOrigin",

packages/core/test/plugin/provider-openai-compatible.test.ts

@@ -1,23 +1,45 @@
 import { describe, expect } from "bun:test"
 import { Effect } from "effect"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { OpenAICompatiblePlugin } from "@opencode-ai/core/plugin/provider/openai-compatible"
-import { addPlugin, it, model } from "./provider-helper"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: OpenAICompatiblePlugin.id, effect: OpenAICompatiblePlugin.effect(host) })
+})
 
 describe("OpenAICompatiblePlugin", () => {
   it.effect("preserves explicit includeUsage false and defaults it to true", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, OpenAICompatiblePlugin)
+      yield* addPlugin()
       const defaulted = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("custom", "model"), package: "@ai-sdk/openai-compatible", options: { name: "custom" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/openai-compatible",
+          options: { name: "custom" },
+        },
         {},
       )
       const disabled = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom", "model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/openai-compatible",
           options: { name: "custom", includeUsage: false },
         },
@@ -31,11 +53,14 @@ describe("OpenAICompatiblePlugin", () => {
   it.effect("defaults includeUsage for OpenAI-compatible package matches", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, OpenAICompatiblePlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom", "model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "test-provider" },
+          }),
           package: "file:///tmp/@ai-sdk/openai-compatible-provider.js",
           options: { name: "custom" },
         },
@@ -49,20 +74,19 @@ describe("OpenAICompatiblePlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const observed: string[] = []
-      yield* addPlugin(plugin, OpenAICompatiblePlugin)
-      yield* plugin.add({
-        id: PluginV2.ID.make("inspector"),
-        effect: Effect.succeed({
-          "aisdk.sdk": (evt) =>
-            Effect.sync(() => {
-              observed.push(evt.sdk.languageModel("model").provider)
-            }),
+      yield* addPlugin()
+      yield* plugin.hook("aisdk.sdk", (event) =>
+        Effect.sync(() => {
+          observed.push(event.sdk.languageModel("model").provider)
         }),
-      })
+      )
       yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-provider", "model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-provider"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/openai-compatible",
           options: { name: "custom-provider", baseURL: "https://example.com/v1" },
         },
@@ -85,11 +109,14 @@ describe("OpenAICompatiblePlugin", () => {
             }),
         }),
       })
-      yield* addPlugin(plugin, OpenAICompatiblePlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("cloudflare-workers-ai", "model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("cloudflare-workers-ai"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/openai-compatible",
           options: { name: "cloudflare-workers-ai" },
         },

packages/core/test/plugin/provider-openai.test.ts

@@ -1,28 +1,50 @@
 import { describe, expect } from "bun:test"
+import type { LanguageModelV3 } from "@ai-sdk/provider"
 import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
 import { Integration } from "@opencode-ai/core/integration"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { OpenAIPlugin } from "@opencode-ai/core/plugin/provider/openai"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { fakeSelectorSdk, it, model, provider, required } from "./provider-helper"
-import { host, integrationHost } from "./host"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
 
-function add(plugin: PluginV2.Interface, integrations: Integration.Interface) {
-  return plugin.add({
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  const integrations = yield* Integration.Service
+  yield* plugin.add({
     id: OpenAIPlugin.id,
-    effect: OpenAIPlugin.effect(host({ integration: integrationHost(integrations) })).pipe(
-      Effect.provideService(Integration.Service, integrations),
-    ),
+    effect: OpenAIPlugin.effect(host).pipe(Effect.provideService(Integration.Service, integrations)),
   })
+})
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
+
+function fakeSelectorSdk(calls: string[]) {
+  const make = (method: string) => (id: string) => {
+    calls.push(`${method}:${id}`)
+    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+  return {
+    responses: make("responses"),
+    messages: make("messages"),
+    chat: make("chat"),
+    languageModel: make("languageModel"),
+  }
 }
 
 describe("OpenAIPlugin", () => {
   it.effect("registers browser and headless ChatGPT OAuth methods", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
-      yield* add(plugin, yield* Integration.Service)
+      yield* addPlugin()
       expect((yield* (yield* Integration.Service).get(Integration.ID.make("openai")))?.methods).toEqual([
         {
           id: Integration.MethodID.make("chatgpt-browser"),
@@ -41,11 +63,14 @@ describe("OpenAIPlugin", () => {
   it.effect("creates an OpenAI SDK for @ai-sdk/openai using the provider ID as SDK name", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* add(plugin, yield* Integration.Service)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-openai", "gpt-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-openai"), ModelV2.ID.make("gpt-5")),
+            api: { id: ModelV2.ID.make("gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/openai",
           options: { name: "custom-openai", apiKey: "test" },
         },
@@ -58,10 +83,17 @@ describe("OpenAIPlugin", () => {
   it.effect("ignores non-OpenAI SDK packages", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* add(plugin, yield* Integration.Service)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("openai", "gpt-5"), package: "@ai-sdk/openai-compatible", options: { name: "openai" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.openai, ModelV2.ID.make("gpt-5")),
+            api: { id: ModelV2.ID.make("gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/openai-compatible",
+          options: { name: "openai" },
+        },
         {},
       )
       expect(result.sdk).toBeUndefined()
@@ -72,11 +104,12 @@ describe("OpenAIPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* add(plugin, yield* Integration.Service)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("openai", "alias", {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.openai, ModelV2.ID.make("alias")),
             api: { id: ModelV2.ID.make("gpt-5"), type: "aisdk", package: "test-provider" },
           }),
           sdk: fakeSelectorSdk(calls),
@@ -93,10 +126,17 @@ describe("OpenAIPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* add(plugin, yield* Integration.Service)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.language",
-        { model: model("anthropic", "gpt-5"), sdk: fakeSelectorSdk(calls), options: {} },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.anthropic, ModelV2.ID.make("gpt-5")),
+            api: { id: ModelV2.ID.make("gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
+          sdk: fakeSelectorSdk(calls),
+          options: {},
+        },
         {},
       )
       expect(calls).toEqual([])
@@ -106,34 +146,43 @@ describe("OpenAIPlugin", () => {
 
   it.effect("disables gpt-5-chat-latest during catalog transforms", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* add(plugin, yield* Integration.Service)
       yield* catalog.transform((catalog) => {
-        const item = provider("openai", { api: { type: "aisdk", package: "@ai-sdk/openai" } })
+        const item = new ProviderV2.Info({
+          ...ProviderV2.Info.empty(ProviderV2.ID.openai),
+          api: { type: "aisdk", package: "@ai-sdk/openai" },
+        })
         catalog.provider.update(item.id, (draft) => {
           draft.api = item.api
         })
         catalog.model.update(item.id, ModelV2.ID.make("gpt-5"), () => {})
         catalog.model.update(item.id, ModelV2.ID.make("gpt-5-chat-latest"), () => {})
       })
+      yield* addPlugin()
       expect(required(yield* catalog.model.get(ProviderV2.ID.openai, ModelV2.ID.make("gpt-5"))).enabled).toBe(true)
-      expect(required(yield* catalog.model.get(ProviderV2.ID.openai, ModelV2.ID.make("gpt-5-chat-latest"))).enabled).toBe(false)
+      expect(
+        required(yield* catalog.model.get(ProviderV2.ID.openai, ModelV2.ID.make("gpt-5-chat-latest"))).enabled,
+      ).toBe(false)
     }),
   )
 
   it.effect("does not disable gpt-5-chat-latest for non-OpenAI providers", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* add(plugin, yield* Integration.Service)
       yield* catalog.transform((catalog) => {
-        const item = provider("custom-openai")
-        catalog.provider.update(item.id, () => {})
+        const item = new ProviderV2.Info({
+          ...ProviderV2.Info.empty(ProviderV2.ID.make("custom-openai")),
+          api: { type: "aisdk", package: "test-provider" },
+        })
+        catalog.provider.update(item.id, (draft) => {
+          draft.api = item.api
+        })
         catalog.model.update(item.id, ModelV2.ID.make("gpt-5-chat-latest"), () => {})
       })
+      yield* addPlugin()
       expect(
-        required(yield* catalog.model.get(ProviderV2.ID.make("custom-openai"), ModelV2.ID.make("gpt-5-chat-latest"))).enabled,
+        required(yield* catalog.model.get(ProviderV2.ID.make("custom-openai"), ModelV2.ID.make("gpt-5-chat-latest")))
+          .enabled,
       ).toBe(true)
     }),
   )

packages/core/test/plugin/provider-opencode.test.ts

@@ -1,47 +1,72 @@
 import { describe, expect } from "bun:test"
-import { Effect, Layer, Option } from "effect"
+import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
-import { Credential } from "@opencode-ai/core/credential"
-import { EventV2 } from "@opencode-ai/core/event"
 import { Integration } from "@opencode-ai/core/integration"
-import { Location } from "@opencode-ai/core/location"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { OpencodePlugin } from "@opencode-ai/core/plugin/provider/opencode"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { AbsolutePath } from "@opencode-ai/core/schema"
-import { location } from "../fixture/location"
-import { it, model, provider, required, withEnv } from "./provider-helper"
-import { catalogHost, host, integrationHost } from "./host"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: OpencodePlugin.id, effect: OpencodePlugin.effect(host) })
+})
+
+function required<T>(value: T | undefined): T {
+  if (value === undefined) throw new Error("Expected value")
+  return value
+}
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, effect: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    effect,
+    (previous) =>
+      Effect.sync(() =>
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        }),
+      ),
+  )
+}
 
 const cost = (input: number, output = 0) => [{ input, output, cache: { read: 0, write: 0 } }]
-const locationLayer = Layer.succeed(
-  Location.Service,
-  Location.Service.of(location({ directory: AbsolutePath.make("test") })),
-)
-
-const pluginWithIntegrations = (catalog: Catalog.Interface, integrations: Integration.Interface) => ({
-  ...OpencodePlugin,
-  effect: OpencodePlugin.effect(
-    host({ catalog: catalogHost(catalog), integration: integrationHost(integrations) }),
-  ),
-})
 
 describe("OpencodePlugin", () => {
   it.effect("uses a public key and disables paid models without credentials", () =>
     withEnv({ OPENCODE_API_KEY: undefined }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
-        yield* plugin.add(pluginWithIntegrations(catalog, yield* Integration.Service))
         yield* catalog.transform((catalog) => {
-          const item = provider("opencode")
-          catalog.provider.update(item.id, () => {})
-          const paid = model("opencode", "paid", { cost: cost(1) })
-          catalog.model.update(item.id, paid.id, (draft) => {
-            draft.cost = [...paid.cost]
+          const provider = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.opencode),
+            api: { type: "aisdk", package: "test-provider" },
+          })
+          const model = new ModelV2.Info({
+            ...ModelV2.Info.empty(provider.id, ModelV2.ID.make("paid")),
+            api: { id: ModelV2.ID.make("paid"), type: "aisdk", package: "test-provider" },
+            cost: cost(1),
+          })
+          catalog.provider.update(provider.id, () => {})
+          catalog.model.update(provider.id, model.id, (draft) => {
+            draft.cost = [...model.cost]
           })
         })
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.opencode)).request.body.apiKey).toBe("public")
         expect(required(yield* catalog.model.get(ProviderV2.ID.opencode, ModelV2.ID.make("paid"))).enabled).toBe(false)
       }),
@@ -51,17 +76,23 @@ describe("OpencodePlugin", () => {
   it.effect("keeps free models without credentials", () =>
     withEnv({ OPENCODE_API_KEY: undefined }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
-        yield* plugin.add(pluginWithIntegrations(catalog, yield* Integration.Service))
         yield* catalog.transform((catalog) => {
-          const item = provider("opencode")
-          catalog.provider.update(item.id, () => {})
-          const free = model("opencode", "free", { cost: cost(0) })
-          catalog.model.update(item.id, free.id, (draft) => {
-            draft.cost = [...free.cost]
+          const provider = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.opencode),
+            api: { type: "aisdk", package: "test-provider" },
+          })
+          const model = new ModelV2.Info({
+            ...ModelV2.Info.empty(provider.id, ModelV2.ID.make("free")),
+            api: { id: ModelV2.ID.make("free"), type: "aisdk", package: "test-provider" },
+            cost: cost(0),
+          })
+          catalog.provider.update(provider.id, () => {})
+          catalog.model.update(provider.id, model.id, (draft) => {
+            draft.cost = [...model.cost]
           })
         })
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.opencode)).request.body.apiKey).toBe("public")
         expect(required(yield* catalog.model.get(ProviderV2.ID.opencode, ModelV2.ID.make("free"))).enabled).toBe(true)
       }),
@@ -71,19 +102,27 @@ describe("OpencodePlugin", () => {
   it.effect("treats output-only cost as free without credentials", () =>
     withEnv({ OPENCODE_API_KEY: undefined }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
-        yield* plugin.add(pluginWithIntegrations(catalog, yield* Integration.Service))
         yield* catalog.transform((catalog) => {
-          const item = provider("opencode")
-          catalog.provider.update(item.id, () => {})
-          const outputOnly = model("opencode", "output-only", { cost: cost(0, 1) })
-          catalog.model.update(item.id, outputOnly.id, (draft) => {
-            draft.cost = [...outputOnly.cost]
+          const provider = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.opencode),
+            api: { type: "aisdk", package: "test-provider" },
+          })
+          const model = new ModelV2.Info({
+            ...ModelV2.Info.empty(provider.id, ModelV2.ID.make("output-only")),
+            api: { id: ModelV2.ID.make("output-only"), type: "aisdk", package: "test-provider" },
+            cost: cost(0, 1),
+          })
+          catalog.provider.update(provider.id, () => {})
+          catalog.model.update(provider.id, model.id, (draft) => {
+            draft.cost = [...model.cost]
           })
         })
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.opencode)).request.body.apiKey).toBe("public")
-        expect(required(yield* catalog.model.get(ProviderV2.ID.opencode, ModelV2.ID.make("output-only"))).enabled).toBe(true)
+        expect(required(yield* catalog.model.get(ProviderV2.ID.opencode, ModelV2.ID.make("output-only"))).enabled).toBe(
+          true,
+        )
       }),
     ),
   )
@@ -91,17 +130,23 @@ describe("OpencodePlugin", () => {
   it.effect("uses OPENCODE_API_KEY as credentials", () =>
     withEnv({ OPENCODE_API_KEY: "secret" }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
-        yield* plugin.add(pluginWithIntegrations(catalog, yield* Integration.Service))
         yield* catalog.transform((catalog) => {
-          const item = provider("opencode")
-          catalog.provider.update(item.id, () => {})
-          const paid = model("opencode", "paid", { cost: cost(1) })
-          catalog.model.update(item.id, paid.id, (draft) => {
-            draft.cost = [...paid.cost]
+          const provider = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.opencode),
+            api: { type: "aisdk", package: "test-provider" },
+          })
+          const model = new ModelV2.Info({
+            ...ModelV2.Info.empty(provider.id, ModelV2.ID.make("paid")),
+            api: { id: ModelV2.ID.make("paid"), type: "aisdk", package: "test-provider" },
+            cost: cost(1),
+          })
+          catalog.provider.update(provider.id, () => {})
+          catalog.model.update(provider.id, model.id, (draft) => {
+            draft.cost = [...model.cost]
           })
         })
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.opencode)).request.body.apiKey).toBeUndefined()
         expect(required(yield* catalog.model.get(ProviderV2.ID.opencode, ModelV2.ID.make("paid"))).enabled).toBe(true)
       }),
@@ -111,10 +156,8 @@ describe("OpencodePlugin", () => {
   it.effect("uses configured provider env vars as credentials", () =>
     withEnv({ OPENCODE_API_KEY: undefined, CUSTOM_OPENCODE_API_KEY: "secret" }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
         const integrations = yield* Integration.Service
-        yield* plugin.add(pluginWithIntegrations(catalog, integrations))
         yield* integrations.transform((editor) => {
           editor.method.update({
             integrationID: Integration.ID.make("opencode"),
@@ -122,13 +165,21 @@ describe("OpencodePlugin", () => {
           })
         })
         yield* catalog.transform((catalog) => {
-          const item = provider("opencode")
-          catalog.provider.update(item.id, () => {})
-          const paid = model("opencode", "paid", { cost: cost(1) })
-          catalog.model.update(item.id, paid.id, (draft) => {
-            draft.cost = [...paid.cost]
+          const provider = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.opencode),
+            api: { type: "aisdk", package: "test-provider" },
+          })
+          const model = new ModelV2.Info({
+            ...ModelV2.Info.empty(provider.id, ModelV2.ID.make("paid")),
+            api: { id: ModelV2.ID.make("paid"), type: "aisdk", package: "test-provider" },
+            cost: cost(1),
+          })
+          catalog.provider.update(provider.id, () => {})
+          catalog.model.update(provider.id, model.id, (draft) => {
+            draft.cost = [...model.cost]
           })
         })
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.opencode)).request.body.apiKey).toBeUndefined()
         expect(required(yield* catalog.model.get(ProviderV2.ID.opencode, ModelV2.ID.make("paid"))).enabled).toBe(true)
       }),
@@ -138,24 +189,29 @@ describe("OpencodePlugin", () => {
   it.effect("uses configured apiKey as credentials", () =>
     withEnv({ OPENCODE_API_KEY: undefined }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
-        yield* plugin.add(pluginWithIntegrations(catalog, yield* Integration.Service))
         yield* catalog.transform((catalog) => {
-          const item = provider("opencode", {
+          const provider = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.opencode),
+            api: { type: "aisdk", package: "test-provider" },
             request: {
               headers: {},
               body: { apiKey: "configured" },
             },
           })
-          catalog.provider.update(item.id, (draft) => {
-            draft.request = item.request
+          const model = new ModelV2.Info({
+            ...ModelV2.Info.empty(provider.id, ModelV2.ID.make("paid")),
+            api: { id: ModelV2.ID.make("paid"), type: "aisdk", package: "test-provider" },
+            cost: cost(1),
           })
-          const paid = model("opencode", "paid", { cost: cost(1) })
-          catalog.model.update(item.id, paid.id, (draft) => {
-            draft.cost = [...paid.cost]
+          catalog.provider.update(provider.id, (draft) => {
+            draft.request = provider.request
+          })
+          catalog.model.update(provider.id, model.id, (draft) => {
+            draft.cost = [...model.cost]
           })
         })
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.opencode)).request.body.apiKey).toBe("configured")
         expect(required(yield* catalog.model.get(ProviderV2.ID.opencode, ModelV2.ID.make("paid"))).enabled).toBe(true)
       }),
@@ -165,17 +221,23 @@ describe("OpencodePlugin", () => {
   it.effect("ignores non-opencode providers and models", () =>
     withEnv({ OPENCODE_API_KEY: undefined }, () =>
       Effect.gen(function* () {
-        const plugin = yield* PluginV2.Service
         const catalog = yield* Catalog.Service
-        yield* plugin.add(pluginWithIntegrations(catalog, yield* Integration.Service))
         yield* catalog.transform((catalog) => {
-          const item = provider("openai")
-          catalog.provider.update(item.id, () => {})
-          const paid = model("openai", "paid", { cost: cost(1) })
-          catalog.model.update(item.id, paid.id, (draft) => {
-            draft.cost = [...paid.cost]
+          const provider = new ProviderV2.Info({
+            ...ProviderV2.Info.empty(ProviderV2.ID.openai),
+            api: { type: "aisdk", package: "test-provider" },
+          })
+          const model = new ModelV2.Info({
+            ...ModelV2.Info.empty(provider.id, ModelV2.ID.make("paid")),
+            api: { id: ModelV2.ID.make("paid"), type: "aisdk", package: "test-provider" },
+            cost: cost(1),
+          })
+          catalog.provider.update(provider.id, () => {})
+          catalog.model.update(provider.id, model.id, (draft) => {
+            draft.cost = [...model.cost]
           })
         })
+        yield* addPlugin()
         expect(required(yield* catalog.provider.get(ProviderV2.ID.openai)).request.body.apiKey).toBeUndefined()
         expect(required(yield* catalog.model.get(ProviderV2.ID.openai, ModelV2.ID.make("paid"))).enabled).toBe(true)
       }),
@@ -206,8 +268,6 @@ describe("OpencodePlugin", () => {
       const selected = yield* catalog.model.small(providerID)
 
       expect(selected?.id).toBe(ModelV2.ID.make("gpt-5-nano"))
-    }).pipe(
-      Effect.provide(Catalog.locationLayer.pipe(Layer.provide(EventV2.defaultLayer), Layer.provide(locationLayer))),
-    ),
+    }),
   )
 })

packages/core/test/plugin/provider-openrouter.test.ts

@@ -3,56 +3,59 @@ import { Effect } from "effect"
 import { Catalog } from "@opencode-ai/core/catalog"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { ProviderPlugins } from "@opencode-ai/core/plugin/provider"
 import { OpenRouterPlugin } from "@opencode-ai/core/plugin/provider/openrouter"
 import { ProviderV2 } from "@opencode-ai/core/provider"
-import { addPlugin, expectPluginRegistered, it, model, provider, required } from "./provider-helper"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: OpenRouterPlugin.id, effect: OpenRouterPlugin.effect(host) })
+})
 
 describe("OpenRouterPlugin", () => {
   it.effect("is registered so legacy OpenRouter behavior can be applied", () =>
-    Effect.sync(() =>
-      expectPluginRegistered(
-        ProviderPlugins.map((item) => item.id),
-        "openrouter",
-      ),
-    ),
+    Effect.sync(() => expect(ProviderPlugins.map((item) => item.id)).toContain(PluginV2.ID.make("openrouter"))),
   )
 
   it.effect("applies legacy referer headers only to openrouter", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, OpenRouterPlugin)
       yield* catalog.transform((catalog) => {
-        const openrouter = provider("openrouter", {
-          api: { type: "aisdk", package: "@openrouter/ai-sdk-provider" },
-          request: { headers: { Existing: "value" }, body: {} },
-        })
-        catalog.provider.update(openrouter.id, (item) => {
-          item.api = openrouter.api
-          item.request = openrouter.request
+        catalog.provider.update(ProviderV2.ID.openrouter, (provider) => {
+          provider.api = { type: "aisdk", package: "@openrouter/ai-sdk-provider" }
+          provider.request = { headers: { Existing: "value" }, body: {} }
         })
         catalog.provider.update(ProviderV2.ID.make("nvidia"), () => {})
       })
+      yield* addPlugin()
 
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("openrouter"))).request.headers).toEqual({
+      expect((yield* catalog.provider.get(ProviderV2.ID.openrouter))?.request.headers).toEqual({
         Existing: "value",
         "HTTP-Referer": "https://opencode.ai/",
         "X-Title": "opencode",
       })
-      expect(required(yield* catalog.provider.get(ProviderV2.ID.make("nvidia"))).request.headers).toEqual({})
+      expect((yield* catalog.provider.get(ProviderV2.ID.make("nvidia")))?.request.headers).toEqual({})
     }),
   )
 
   it.effect("creates an SDK only for the OpenRouter package", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, OpenRouterPlugin)
+      yield* addPlugin()
 
       const ignored = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("openrouter", "openai/gpt-5"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.openrouter, ModelV2.ID.make("openai/gpt-5")),
+            api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/openai-compatible",
           options: { name: "openrouter" },
         },
@@ -62,7 +65,14 @@ describe("OpenRouterPlugin", () => {
 
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("custom", "openai/gpt-5"), package: "@openrouter/ai-sdk-provider", options: { name: "custom" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom"), ModelV2.ID.make("openai/gpt-5")),
+            api: { id: ModelV2.ID.make("openai/gpt-5"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@openrouter/ai-sdk-provider",
+          options: { name: "custom" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -71,48 +81,37 @@ describe("OpenRouterPlugin", () => {
 
   it.effect("filters OpenRouter's gpt-5 chat alias", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, OpenRouterPlugin)
       yield* catalog.transform((catalog) => {
-        const openrouter = provider("openrouter", {
-          api: { type: "aisdk", package: "@openrouter/ai-sdk-provider" },
-        })
-        catalog.provider.update(openrouter.id, (item) => {
-          item.api = openrouter.api
+        catalog.provider.update(ProviderV2.ID.openrouter, (provider) => {
+          provider.api = { type: "aisdk", package: "@openrouter/ai-sdk-provider" }
         })
         catalog.provider.update(ProviderV2.ID.openai, () => {})
-        for (const item of [
-          model("openrouter", "openai/gpt-5-chat"),
-          model("openrouter", "openai/gpt-5"),
-          model("openai", "openai/gpt-5-chat"),
-        ]) {
-          catalog.model.update(item.providerID, item.id, () => {})
-        }
+        catalog.model.update(ProviderV2.ID.openrouter, ModelV2.ID.make("openai/gpt-5-chat"), () => {})
+        catalog.model.update(ProviderV2.ID.openrouter, ModelV2.ID.make("openai/gpt-5"), () => {})
+        catalog.model.update(ProviderV2.ID.openai, ModelV2.ID.make("openai/gpt-5-chat"), () => {})
       })
+      yield* addPlugin()
 
-      expect(
-        required(yield* catalog.model.get(ProviderV2.ID.make("openrouter"), ModelV2.ID.make("openai/gpt-5-chat"))).enabled,
-      ).toBe(false)
-      expect(
-        required(yield* catalog.model.get(ProviderV2.ID.make("openrouter"), ModelV2.ID.make("openai/gpt-5"))).enabled,
-      ).toBe(true)
-      expect(required(yield* catalog.model.get(ProviderV2.ID.openai, ModelV2.ID.make("openai/gpt-5-chat"))).enabled).toBe(true)
+      expect((yield* catalog.model.get(ProviderV2.ID.openrouter, ModelV2.ID.make("openai/gpt-5-chat")))?.enabled).toBe(
+        false,
+      )
+      expect((yield* catalog.model.get(ProviderV2.ID.openrouter, ModelV2.ID.make("openai/gpt-5")))?.enabled).toBe(true)
+      expect((yield* catalog.model.get(ProviderV2.ID.openai, ModelV2.ID.make("openai/gpt-5-chat")))?.enabled).toBe(true)
     }),
   )
 
   it.effect("does not disable gpt-5-chat-latest for non-OpenRouter providers", () =>
     Effect.gen(function* () {
-      const plugin = yield* PluginV2.Service
       const catalog = yield* Catalog.Service
-      yield* addPlugin(plugin, OpenRouterPlugin)
       yield* catalog.transform((catalog) => {
         catalog.provider.update(ProviderV2.ID.make("custom-openrouter"), () => {})
         catalog.model.update(ProviderV2.ID.make("custom-openrouter"), ModelV2.ID.make("gpt-5-chat-latest"), () => {})
       })
+      yield* addPlugin()
       expect(
-        required(yield* catalog.model.get(ProviderV2.ID.make("custom-openrouter"), ModelV2.ID.make("gpt-5-chat-latest")))
-          .enabled,
+        (yield* catalog.model.get(ProviderV2.ID.make("custom-openrouter"), ModelV2.ID.make("gpt-5-chat-latest")))
+          ?.enabled,
       ).toBe(true)
     }),
   )

packages/core/test/plugin/provider-perplexity.test.ts

@@ -1,18 +1,50 @@
 import { describe, expect } from "bun:test"
+import type { LanguageModelV3 } from "@ai-sdk/provider"
 import { Effect } from "effect"
 import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { PerplexityPlugin } from "@opencode-ai/core/plugin/provider/perplexity"
-import { addPlugin, fakeSelectorSdk, it, model } from "./provider-helper"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: PerplexityPlugin.id, effect: PerplexityPlugin.effect(host) })
+})
+
+function fakeSelectorSdk(calls: string[]) {
+  const make = (method: string) => (id: string) => {
+    calls.push(`${method}:${id}`)
+    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+  return {
+    responses: make("responses"),
+    messages: make("messages"),
+    chat: make("chat"),
+    languageModel: make("languageModel"),
+  }
+}
 
 describe("PerplexityPlugin", () => {
   it.effect("creates a Perplexity SDK for the exact @ai-sdk/perplexity package", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, PerplexityPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("perplexity", "sonar"), package: "@ai-sdk/perplexity", options: { name: "perplexity" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("perplexity"), ModelV2.ID.make("sonar")),
+            api: { id: ModelV2.ID.make("sonar"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/perplexity",
+          options: { name: "perplexity" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -22,11 +54,14 @@ describe("PerplexityPlugin", () => {
   it.effect("ignores packages that are not the bundled Perplexity package", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, PerplexityPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("perplexity", "sonar"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("perplexity"), ModelV2.ID.make("sonar")),
+            api: { id: ModelV2.ID.make("sonar"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/perplexity-compatible",
           options: { name: "perplexity" },
         },
@@ -39,50 +74,40 @@ describe("PerplexityPlugin", () => {
   it.effect("uses the Perplexity provider ID as the SDK name for the bundled provider", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      const providers: string[] = []
-      yield* addPlugin(plugin, PerplexityPlugin)
-      yield* plugin.add({
-        id: PluginV2.ID.make("perplexity-sdk-inspector"),
-        effect: Effect.succeed({
-          "aisdk.sdk": (evt) =>
-            Effect.sync(() => {
-              providers.push(evt.sdk.languageModel("sonar").provider)
-            }),
-        }),
-      })
-      yield* plugin.trigger(
+      yield* addPlugin()
+      const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("perplexity", "sonar"), package: "@ai-sdk/perplexity", options: { name: "perplexity" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("perplexity"), ModelV2.ID.make("sonar")),
+            api: { id: ModelV2.ID.make("sonar"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/perplexity",
+          options: { name: "perplexity" },
+        },
         {},
       )
-      expect(providers).toEqual(["perplexity"])
+      expect(result.sdk.languageModel("sonar").provider).toBe("perplexity")
     }),
   )
 
   it.effect("creates bundled Perplexity SDKs for custom provider IDs", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      const providers: string[] = []
-      yield* addPlugin(plugin, PerplexityPlugin)
-      yield* plugin.add({
-        id: PluginV2.ID.make("custom-perplexity-sdk-inspector"),
-        effect: Effect.succeed({
-          "aisdk.sdk": (evt) =>
-            Effect.sync(() => {
-              providers.push(evt.sdk.languageModel("sonar").provider)
-            }),
-        }),
-      })
-      yield* plugin.trigger(
+      yield* addPlugin()
+      const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-perplexity", "sonar"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-perplexity"), ModelV2.ID.make("sonar")),
+            api: { id: ModelV2.ID.make("sonar"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/perplexity",
           options: { name: "custom-perplexity" },
         },
         {},
       )
-      expect(providers).toEqual(["perplexity"])
+      expect(result.sdk.languageModel("sonar").provider).toBe("perplexity")
     }),
   )
 
@@ -90,11 +115,14 @@ describe("PerplexityPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, PerplexityPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("perplexity", "alias", { api: { id: ModelV2.ID.make("sonar") } }),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("perplexity"), ModelV2.ID.make("alias")),
+            api: { id: ModelV2.ID.make("sonar"), type: "aisdk", package: "test-provider" },
+          }),
           sdk: fakeSelectorSdk(calls),
           options: {},
         },

packages/core/test/plugin/provider-sap-ai-core.test.ts

@@ -1,16 +1,54 @@
 import { describe, expect } from "bun:test"
 import { Effect } from "effect"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { Npm } from "@opencode-ai/core/npm"
 import { SapAICorePlugin } from "@opencode-ai/core/plugin/provider/sap-ai-core"
-import { fixtureProvider, it, model, npmLayer, withEnv } from "./provider-helper"
-import { host } from "./host"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
 
-const pluginWithNpm = {
-  id: SapAICorePlugin.id,
-  effect: Effect.gen(function* () {
-    yield* SapAICorePlugin.effect(host({ npm: yield* Npm.Service }))
-  }).pipe(Effect.provide(npmLayer)),
+const fixtureProvider = new URL("./fixtures/provider-factory.ts", import.meta.url).href
+const it = testEffect(PluginTestLayer)
+const npm = Npm.Service.of({
+  add: () => Effect.succeed({ directory: "", entrypoint: undefined }),
+  install: () => Effect.void,
+  which: () => Effect.succeed(undefined),
+})
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: SapAICorePlugin.id, effect: SapAICorePlugin.effect({ ...host, npm }) })
+})
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, effect: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      for (const [key, value] of Object.entries(vars)) {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      }
+      return previous
+    }),
+    effect,
+    (previous) =>
+      Effect.sync(() => {
+        for (const [key, value] of Object.entries(previous)) {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        }
+      }),
+  )
+}
+
+function model(providerID: string) {
+  return new ModelV2.Info({
+    ...ModelV2.Info.empty(ProviderV2.ID.make(providerID), ModelV2.ID.make("sap-model")),
+    api: { id: ModelV2.ID.make("sap-model"), type: "aisdk", package: fixtureProvider },
+  })
 }
 
 describe("SapAICorePlugin", () => {
@@ -20,11 +58,11 @@ describe("SapAICorePlugin", () => {
       () =>
         Effect.gen(function* () {
           const plugin = yield* PluginV2.Service
-          yield* plugin.add(pluginWithNpm)
+          yield* addPlugin()
           const sdk = yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("sap-ai-core", "sap-model"),
+              model: model("sap-ai-core"),
               package: fixtureProvider,
               options: { name: "sap-ai-core", serviceKey: "service-key" },
             },
@@ -46,11 +84,11 @@ describe("SapAICorePlugin", () => {
       () =>
         Effect.gen(function* () {
           const plugin = yield* PluginV2.Service
-          yield* plugin.add(pluginWithNpm)
+          yield* addPlugin()
           const sdk = yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("sap-ai-core", "sap-model"),
+              model: model("sap-ai-core"),
               package: fixtureProvider,
               options: { name: "sap-ai-core", serviceKey: "option-service-key" },
             },
@@ -68,10 +106,10 @@ describe("SapAICorePlugin", () => {
       () =>
         Effect.gen(function* () {
           const plugin = yield* PluginV2.Service
-          yield* plugin.add(pluginWithNpm)
+          yield* addPlugin()
           const sdk = yield* plugin.trigger(
             "aisdk.sdk",
-            { model: model("sap-ai-core", "sap-model"), package: fixtureProvider, options: { name: "sap-ai-core" } },
+            { model: model("sap-ai-core"), package: fixtureProvider, options: { name: "sap-ai-core" } },
             {},
           )
           expect(process.env.AICORE_SERVICE_KEY).toBeUndefined()
@@ -83,17 +121,13 @@ describe("SapAICorePlugin", () => {
   it.effect("uses the callable SDK for language selection", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* plugin.add(pluginWithNpm)
+      yield* addPlugin()
       const sdk = Object.assign((modelID: string) => ({ modelID, provider: "callable" }), {
         languageModel() {
           throw new Error("SAP AI Core should call the SDK directly")
         },
       })
-      const language = yield* plugin.trigger(
-        "aisdk.language",
-        { model: model("sap-ai-core", "sap-model"), sdk, options: {} },
-        {},
-      )
+      const language = yield* plugin.trigger("aisdk.language", { model: model("sap-ai-core"), sdk, options: {} }, {})
       expect(language.language as unknown).toEqual({ modelID: "sap-model", provider: "callable" })
     }),
   )
@@ -104,11 +138,11 @@ describe("SapAICorePlugin", () => {
       () =>
         Effect.gen(function* () {
           const plugin = yield* PluginV2.Service
-          yield* plugin.add(pluginWithNpm)
+          yield* addPlugin()
           const sdk = yield* plugin.trigger(
             "aisdk.sdk",
             {
-              model: model("openai", "sap-model"),
+              model: model("openai"),
               package: fixtureProvider,
               options: { name: "openai", serviceKey: "service-key" },
             },
@@ -117,7 +151,7 @@ describe("SapAICorePlugin", () => {
           const language = yield* plugin.trigger(
             "aisdk.language",
             {
-              model: model("openai", "sap-model"),
+              model: model("openai"),
               sdk: () => {
                 throw new Error("SAP AI Core should ignore other providers")
               },

packages/core/test/plugin/provider-snowflake-cortex.test.ts

@@ -1,18 +1,48 @@
 import { describe, expect, it as bun_it } from "bun:test"
 import { Effect } from "effect"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { SnowflakeCortexPlugin, cortexFetch } from "@opencode-ai/core/plugin/provider/snowflake-cortex"
 import { ProviderPlugins } from "@opencode-ai/core/plugin/provider"
-import { addPlugin, expectPluginRegistered, it, model, withEnv } from "./provider-helper"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: SnowflakeCortexPlugin.id, effect: SnowflakeCortexPlugin.effect(host) })
+})
+
+function withEnv<A, E, R>(vars: Record<string, string | undefined>, effect: () => Effect.Effect<A, E, R>) {
+  return Effect.acquireUseRelease(
+    Effect.sync(() => {
+      const previous = Object.fromEntries(Object.keys(vars).map((key) => [key, process.env[key]]))
+      Object.entries(vars).forEach(([key, value]) => {
+        if (value === undefined) delete process.env[key]
+        else process.env[key] = value
+      })
+      return previous
+    }),
+    effect,
+    (previous) =>
+      Effect.sync(() => {
+        Object.entries(previous).forEach(([key, value]) => {
+          if (value === undefined) delete process.env[key]
+          else process.env[key] = value
+        })
+      }),
+  )
+}
 
 describe("SnowflakeCortexPlugin", () => {
   it.effect("is registered in ProviderPlugins before OpenAICompatiblePlugin", () =>
     Effect.sync(() => {
-      expectPluginRegistered(
-        ProviderPlugins.map((item) => item.id),
-        "snowflake-cortex",
-      )
-      const ids = ProviderPlugins.map((p) => p.id as string)
+      expect(ProviderPlugins.map((item) => item.id)).toContain(PluginV2.ID.make("snowflake-cortex"))
+      const ids = ProviderPlugins.map((p) => p.id)
       expect(ids.indexOf("snowflake-cortex")).toBeLessThan(ids.indexOf("openai-compatible"))
     }),
   )
@@ -20,10 +50,17 @@ describe("SnowflakeCortexPlugin", () => {
   it.effect("ignores non-snowflake-cortex providers", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, SnowflakeCortexPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("openai", "gpt-4"), package: "@ai-sdk/openai", options: { name: "openai" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("openai"), ModelV2.ID.make("gpt-4")),
+            api: { id: ModelV2.ID.make("gpt-4"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/openai",
+          options: { name: "openai" },
+        },
         {},
       )
       expect(result.sdk).toBeUndefined()
@@ -34,11 +71,14 @@ describe("SnowflakeCortexPlugin", () => {
     withEnv({ SNOWFLAKE_CORTEX_PAT: "test-pat" }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, SnowflakeCortexPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("snowflake-cortex", "claude-sonnet-4-6"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("snowflake-cortex"), ModelV2.ID.make("claude-sonnet-4-6")),
+              api: { id: ModelV2.ID.make("claude-sonnet-4-6"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/openai-compatible",
             options: { name: "snowflake-cortex", baseURL: "https://test.snowflakecomputing.com/api/v2/cortex/v1" },
           },
@@ -53,11 +93,14 @@ describe("SnowflakeCortexPlugin", () => {
     withEnv({ SNOWFLAKE_CORTEX_PAT: undefined }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, SnowflakeCortexPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("snowflake-cortex", "claude-sonnet-4-6"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("snowflake-cortex"), ModelV2.ID.make("claude-sonnet-4-6")),
+              api: { id: ModelV2.ID.make("claude-sonnet-4-6"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/openai-compatible",
             options: {
               name: "snowflake-cortex",
@@ -76,11 +119,14 @@ describe("SnowflakeCortexPlugin", () => {
     withEnv({ SNOWFLAKE_CORTEX_TOKEN: "oauth-token", SNOWFLAKE_CORTEX_PAT: undefined }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, SnowflakeCortexPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("snowflake-cortex", "claude-sonnet-4-6"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("snowflake-cortex"), ModelV2.ID.make("claude-sonnet-4-6")),
+              api: { id: ModelV2.ID.make("claude-sonnet-4-6"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/openai-compatible",
             options: { name: "snowflake-cortex", baseURL: "https://test.snowflakecomputing.com/api/v2/cortex/v1" },
           },
@@ -95,11 +141,14 @@ describe("SnowflakeCortexPlugin", () => {
     withEnv({ SNOWFLAKE_CORTEX_TOKEN: undefined, SNOWFLAKE_CORTEX_PAT: undefined }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        yield* addPlugin(plugin, SnowflakeCortexPlugin)
+        yield* addPlugin()
         const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("snowflake-cortex", "claude-sonnet-4-6"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("snowflake-cortex"), ModelV2.ID.make("claude-sonnet-4-6")),
+              api: { id: ModelV2.ID.make("claude-sonnet-4-6"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/openai-compatible",
             options: {
               name: "snowflake-cortex",
@@ -118,27 +167,20 @@ describe("SnowflakeCortexPlugin", () => {
     withEnv({ SNOWFLAKE_CORTEX_PAT: "test-pat" }, () =>
       Effect.gen(function* () {
         const plugin = yield* PluginV2.Service
-        const captured: Record<string, unknown>[] = []
-        yield* addPlugin(plugin, SnowflakeCortexPlugin)
-        yield* plugin.add({
-          id: PluginV2.ID.make("inspector"),
-          effect: Effect.succeed({
-            "aisdk.sdk": (evt) =>
-              Effect.sync(() => {
-                captured.push({ ...evt.options })
-              }),
-          }),
-        })
-        yield* plugin.trigger(
+        yield* addPlugin()
+        const result = yield* plugin.trigger(
           "aisdk.sdk",
           {
-            model: model("snowflake-cortex", "claude-sonnet-4-6"),
+            model: new ModelV2.Info({
+              ...ModelV2.Info.empty(ProviderV2.ID.make("snowflake-cortex"), ModelV2.ID.make("claude-sonnet-4-6")),
+              api: { id: ModelV2.ID.make("claude-sonnet-4-6"), type: "aisdk", package: "test-provider" },
+            }),
             package: "@ai-sdk/openai-compatible",
             options: { name: "snowflake-cortex", baseURL: "https://test.snowflakecomputing.com/api/v2/cortex/v1" },
           },
           {},
         )
-        expect(captured[0]?.includeUsage).toBe(true)
+        expect(result.options.includeUsage).toBe(true)
       }),
     ),
   )

packages/core/test/plugin/provider-togetherai.test.ts

@@ -1,17 +1,50 @@
 import { describe, expect } from "bun:test"
+import type { LanguageModelV3 } from "@ai-sdk/provider"
 import { Effect } from "effect"
+import { ModelV2 } from "@opencode-ai/core/model"
 import { PluginV2 } from "@opencode-ai/core/plugin"
+import { PluginHost } from "@opencode-ai/core/plugin/host"
 import { TogetherAIPlugin } from "@opencode-ai/core/plugin/provider/togetherai"
-import { addPlugin, fakeSelectorSdk, it, model } from "./provider-helper"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { testEffect } from "../lib/effect"
+import { PluginTestLayer } from "./fixture"
+
+const it = testEffect(PluginTestLayer)
+
+const addPlugin = Effect.fn(function* () {
+  const plugin = yield* PluginV2.Service
+  const host = yield* PluginHost.make()
+  yield* plugin.add({ id: TogetherAIPlugin.id, effect: TogetherAIPlugin.effect(host) })
+})
+
+function fakeSelectorSdk(calls: string[]) {
+  const make = (method: string) => (id: string) => {
+    calls.push(`${method}:${id}`)
+    return { modelId: id, provider: method, specificationVersion: "v3" } as unknown as LanguageModelV3
+  }
+  return {
+    responses: make("responses"),
+    messages: make("messages"),
+    chat: make("chat"),
+    languageModel: make("languageModel"),
+  }
+}
 
 describe("TogetherAIPlugin", () => {
   it.effect("creates a TogetherAI SDK for @ai-sdk/togetherai", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, TogetherAIPlugin)
+      yield* addPlugin()
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("togetherai", "model"), package: "@ai-sdk/togetherai", options: { name: "togetherai" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("togetherai"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/togetherai",
+          options: { name: "togetherai" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -21,12 +54,15 @@ describe("TogetherAIPlugin", () => {
   it.effect("matches the old bundled provider package exactly", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      yield* addPlugin(plugin, TogetherAIPlugin)
+      yield* addPlugin()
 
       const ignored = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("togetherai", "model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("togetherai"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "test-provider" },
+          }),
           package: "file:///tmp/@ai-sdk/togetherai-provider.js",
           options: { name: "togetherai" },
         },
@@ -36,7 +72,14 @@ describe("TogetherAIPlugin", () => {
 
       const result = yield* plugin.trigger(
         "aisdk.sdk",
-        { model: model("togetherai", "model"), package: "@ai-sdk/togetherai", options: { name: "togetherai" } },
+        {
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("togetherai"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "test-provider" },
+          }),
+          package: "@ai-sdk/togetherai",
+          options: { name: "togetherai" },
+        },
         {},
       )
       expect(result.sdk).toBeDefined()
@@ -46,29 +89,22 @@ describe("TogetherAIPlugin", () => {
   it.effect("creates bundled TogetherAI SDKs for custom provider IDs", () =>
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
-      const observed: string[] = []
-      yield* addPlugin(plugin, TogetherAIPlugin)
-      yield* plugin.add({
-        id: PluginV2.ID.make("inspector"),
-        effect: Effect.succeed({
-          "aisdk.sdk": (evt) =>
-            Effect.sync(() => {
-              observed.push(evt.sdk.languageModel("model").provider)
-            }),
-        }),
-      })
+      yield* addPlugin()
 
-      yield* plugin.trigger(
+      const result = yield* plugin.trigger(
         "aisdk.sdk",
         {
-          model: model("custom-togetherai", "model"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(ProviderV2.ID.make("custom-togetherai"), ModelV2.ID.make("model")),
+            api: { id: ModelV2.ID.make("model"), type: "aisdk", package: "test-provider" },
+          }),
           package: "@ai-sdk/togetherai",
           options: { name: "custom-togetherai" },
         },
         {},
       )
 
-      expect(observed).toEqual(["togetherai.chat"])
+      expect(result.sdk.languageModel("model").provider).toBe("togetherai.chat")
     }),
   )
 
@@ -76,12 +112,22 @@ describe("TogetherAIPlugin", () => {
     Effect.gen(function* () {
       const plugin = yield* PluginV2.Service
       const calls: string[] = []
-      yield* addPlugin(plugin, TogetherAIPlugin)
+      yield* addPlugin()
 
       const result = yield* plugin.trigger(
         "aisdk.language",
         {
-          model: model("togetherai", "meta-llama/Llama-3.3-70B-Instruct-Turbo"),
+          model: new ModelV2.Info({
+            ...ModelV2.Info.empty(
+              ProviderV2.ID.make("togetherai"),
+              ModelV2.ID.make("meta-llama/Llama-3.3-70B-Instruct-Turbo"),
+            ),
+            api: {
+              id: ModelV2.ID.make("meta-llama/Llama-3.3-70B-Instruct-Turbo"),
+              type: "aisdk",
+              package: "test-provider",
+            },
+          }),
           sdk: { languageModel: fakeSelectorSdk(calls).languageModel },
           options: {},
         },