feat(aircoding): AirCoding V2 baseline — deterministic multi-agent architecture

Forked from OpenCode v1.17.4 with multi-agent system:
- 5 agents: aircoding, scheduler, worker, architect, reviewer
- Deterministic DAG scheduling engine (coordinator_tick)
- Tool whitelists as hard enforcement
- AirCoding validation plugin
- V1 requirements: C4 docs, ADR, AGENTS.md, debug-log.md
- Design documents in docs/

packages/opencode/test/session/instruction.test.ts

@@ -0,0 +1,256 @@
+import { describe, expect, test } from "bun:test"
+import { SessionV1 } from "@opencode-ai/core/v1/session"
+import path from "path"
+import { Effect, FileSystem, Layer } from "effect"
+import { FetchHttpClient } from "effect/unstable/http"
+import { NodeFileSystem } from "@effect/platform-node"
+import { CrossSpawnSpawner } from "@opencode-ai/core/cross-spawn-spawner"
+import { FSUtil } from "@opencode-ai/core/fs-util"
+
+import { Instruction } from "../../src/session/instruction"
+import type { MessageV2 } from "../../src/session/message-v2"
+import { MessageID, PartID, SessionID } from "../../src/session/schema"
+import { Global } from "@opencode-ai/core/global"
+import { RuntimeFlags } from "../../src/effect/runtime-flags"
+import { provideInstance, provideTmpdirInstance, testInstanceStoreLayer, tmpdirScoped } from "../fixture/fixture"
+import { testEffect } from "../lib/effect"
+import { TestConfig } from "../fixture/config"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { ModelV2 } from "@opencode-ai/core/model"
+
+const it = testEffect(Layer.mergeAll(CrossSpawnSpawner.defaultLayer, NodeFileSystem.layer, testInstanceStoreLayer))
+
+const configLayer = TestConfig.layer()
+
+const instructionLayer = (global: Partial<Global.Interface>, flags: Partial<RuntimeFlags.Info> = {}) =>
+  Instruction.layer.pipe(
+    Layer.provide(configLayer),
+    Layer.provide(FSUtil.defaultLayer),
+    Layer.provide(FetchHttpClient.layer),
+    Layer.provide(Global.layerWith(global)),
+    Layer.provide(RuntimeFlags.layer(flags)),
+  )
+
+const provideInstruction =
+  (global: Partial<Global.Interface>, flags?: Partial<RuntimeFlags.Info>) =>
+  <A, E, R>(self: Effect.Effect<A, E, R>) =>
+    self.pipe(Effect.provide(instructionLayer(global, flags)))
+
+const write = (filepath: string, content: string) =>
+  Effect.gen(function* () {
+    const fs = yield* FileSystem.FileSystem
+    yield* fs.makeDirectory(path.dirname(filepath), { recursive: true })
+    yield* fs.writeFileString(filepath, content)
+  })
+
+const writeFiles = (dir: string, files: Record<string, string>) =>
+  Effect.all(
+    Object.entries(files).map(([file, content]) => write(path.join(dir, file), content)),
+    { discard: true },
+  )
+
+const withFiles = <A, E, R>(files: Record<string, string>, self: (dir: string) => Effect.Effect<A, E, R>) =>
+  provideTmpdirInstance((dir) =>
+    Effect.gen(function* () {
+      yield* writeFiles(dir, files)
+      return yield* self(dir).pipe(provideInstruction({ home: dir, config: dir }))
+    }),
+  )
+
+const tmpWithFiles = (files: Record<string, string>) =>
+  Effect.gen(function* () {
+    const dir = yield* tmpdirScoped()
+    yield* writeFiles(dir, files)
+    return dir
+  })
+
+function loaded(filepath: string): SessionV1.WithParts[] {
+  const sessionID = SessionID.make("session-loaded-1")
+  const messageID = MessageID.make("msg_message-loaded-1")
+
+  return [
+    {
+      info: {
+        id: messageID,
+        sessionID,
+        role: "user",
+        time: { created: 0 },
+        agent: "build",
+        model: {
+          providerID: ProviderV2.ID.make("anthropic"),
+          modelID: ModelV2.ID.make("claude-sonnet-4-20250514"),
+        },
+      },
+      parts: [
+        {
+          id: PartID.make("prt_part-loaded-1"),
+          messageID,
+          sessionID,
+          type: "tool",
+          callID: "call-loaded-1",
+          tool: "read",
+          state: {
+            status: "completed",
+            input: {},
+            output: "done",
+            title: "Read",
+            metadata: { loaded: [filepath] },
+            time: { start: 0, end: 1 },
+          },
+        },
+      ],
+    },
+  ]
+}
+
+describe("Instruction.resolve", () => {
+  it.live("returns empty when AGENTS.md is at project root (already in systemPaths)", () =>
+    withFiles({ "AGENTS.md": "# Root Instructions", "src/file.ts": "const x = 1" }, (dir) =>
+      Effect.gen(function* () {
+        const svc = yield* Instruction.Service
+        const system = yield* svc.systemPaths()
+        expect(system.has(path.join(dir, "AGENTS.md"))).toBe(true)
+
+        const results = yield* svc.resolve([], path.join(dir, "src", "file.ts"), MessageID.make("msg_message-test-1"))
+        expect(results).toEqual([])
+      }),
+    ),
+  )
+
+  it.live("returns AGENTS.md from subdirectory (not in systemPaths)", () =>
+    withFiles({ "subdir/AGENTS.md": "# Subdir Instructions", "subdir/nested/file.ts": "const x = 1" }, (dir) =>
+      Effect.gen(function* () {
+        const svc = yield* Instruction.Service
+        const system = yield* svc.systemPaths()
+        expect(system.has(path.join(dir, "subdir", "AGENTS.md"))).toBe(false)
+
+        const results = yield* svc.resolve(
+          [],
+          path.join(dir, "subdir", "nested", "file.ts"),
+          MessageID.make("msg_message-test-2"),
+        )
+        expect(results.length).toBe(1)
+        expect(results[0].filepath).toBe(path.join(dir, "subdir", "AGENTS.md"))
+      }),
+    ),
+  )
+
+  it.live("doesn't reload AGENTS.md when reading it directly", () =>
+    withFiles({ "subdir/AGENTS.md": "# Subdir Instructions", "subdir/nested/file.ts": "const x = 1" }, (dir) =>
+      Effect.gen(function* () {
+        const svc = yield* Instruction.Service
+        const filepath = path.join(dir, "subdir", "AGENTS.md")
+        const system = yield* svc.systemPaths()
+        expect(system.has(filepath)).toBe(false)
+
+        const results = yield* svc.resolve([], filepath, MessageID.make("msg_message-test-3"))
+        expect(results).toEqual([])
+      }),
+    ),
+  )
+
+  it.live("does not reattach the same nearby instructions twice for one message", () =>
+    withFiles({ "subdir/AGENTS.md": "# Subdir Instructions", "subdir/nested/file.ts": "const x = 1" }, (dir) =>
+      Effect.gen(function* () {
+        const svc = yield* Instruction.Service
+        const filepath = path.join(dir, "subdir", "nested", "file.ts")
+        const id = MessageID.make("msg_message-claim-1")
+
+        const first = yield* svc.resolve([], filepath, id)
+        const second = yield* svc.resolve([], filepath, id)
+
+        expect(first).toHaveLength(1)
+        expect(first[0].filepath).toBe(path.join(dir, "subdir", "AGENTS.md"))
+        expect(second).toEqual([])
+      }),
+    ),
+  )
+
+  it.live("clear allows nearby instructions to be attached again for the same message", () =>
+    withFiles({ "subdir/AGENTS.md": "# Subdir Instructions", "subdir/nested/file.ts": "const x = 1" }, (dir) =>
+      Effect.gen(function* () {
+        const svc = yield* Instruction.Service
+        const filepath = path.join(dir, "subdir", "nested", "file.ts")
+        const id = MessageID.make("msg_message-claim-2")
+
+        const first = yield* svc.resolve([], filepath, id)
+        yield* svc.clear(id)
+        const second = yield* svc.resolve([], filepath, id)
+
+        expect(first).toHaveLength(1)
+        expect(second).toHaveLength(1)
+        expect(second[0].filepath).toBe(path.join(dir, "subdir", "AGENTS.md"))
+      }),
+    ),
+  )
+
+  it.live("skips instructions already reported by prior read metadata", () =>
+    withFiles({ "subdir/AGENTS.md": "# Subdir Instructions", "subdir/nested/file.ts": "const x = 1" }, (dir) =>
+      Effect.gen(function* () {
+        const svc = yield* Instruction.Service
+        const agents = path.join(dir, "subdir", "AGENTS.md")
+        const filepath = path.join(dir, "subdir", "nested", "file.ts")
+        const id = MessageID.make("msg_message-claim-3")
+
+        const results = yield* svc.resolve(loaded(agents), filepath, id)
+        expect(results).toEqual([])
+      }),
+    ),
+  )
+
+  test.todo("fetches remote instructions from config URLs via HttpClient", () => {})
+})
+
+describe("Instruction.system", () => {
+  it.live("loads both project and global AGENTS.md when both exist", () =>
+    Effect.gen(function* () {
+      const globalTmp = yield* tmpWithFiles({ "AGENTS.md": "# Global Instructions" })
+      const projectTmp = yield* tmpWithFiles({ "AGENTS.md": "# Project Instructions" })
+
+      yield* Effect.gen(function* () {
+        const svc = yield* Instruction.Service
+        const paths = yield* svc.systemPaths()
+        expect(paths.has(path.join(projectTmp, "AGENTS.md"))).toBe(true)
+        expect(paths.has(path.join(globalTmp, "AGENTS.md"))).toBe(true)
+
+        const rules = yield* svc.system()
+        expect(rules).toHaveLength(2)
+        expect(rules[0]).toBe(`Instructions from: ${path.join(globalTmp, "AGENTS.md")}\n# Global Instructions`)
+        expect(rules[1]).toBe(`Instructions from: ${path.join(projectTmp, "AGENTS.md")}\n# Project Instructions`)
+      }).pipe(provideInstance(projectTmp), provideInstruction({ home: globalTmp, config: globalTmp }))
+    }),
+  )
+
+  it.live("skips project and global CLAUDE.md when Claude Code prompt is disabled", () =>
+    Effect.gen(function* () {
+      const globalTmp = yield* tmpWithFiles({ ".claude/CLAUDE.md": "# Global Claude" })
+      const projectTmp = yield* tmpWithFiles({ "CLAUDE.md": "# Project Claude" })
+
+      yield* Effect.gen(function* () {
+        const svc = yield* Instruction.Service
+        const paths = yield* svc.systemPaths()
+        expect(paths.has(path.join(globalTmp, ".claude", "CLAUDE.md"))).toBe(false)
+        expect(paths.has(path.join(projectTmp, "CLAUDE.md"))).toBe(false)
+        expect(yield* svc.system()).toEqual([])
+      }).pipe(
+        provideInstance(projectTmp),
+        provideInstruction({ home: globalTmp, config: globalTmp }, { disableClaudeCodePrompt: true }),
+      )
+    }),
+  )
+})
+
+describe("Instruction.systemPaths global config", () => {
+  it.live("uses Global.Service config AGENTS.md", () =>
+    Effect.gen(function* () {
+      const globalTmp = yield* tmpWithFiles({ "AGENTS.md": "# Global Instructions" })
+      const projectTmp = yield* tmpdirScoped()
+
+      yield* Effect.gen(function* () {
+        const svc = yield* Instruction.Service
+        const paths = yield* svc.systemPaths()
+        expect(paths.has(path.join(globalTmp, "AGENTS.md"))).toBe(true)
+      }).pipe(provideInstance(projectTmp), provideInstruction({ home: globalTmp, config: globalTmp }))
+    }),
+  )
+})

packages/opencode/test/session/llm-native-recorded.test.ts

@@ -0,0 +1,433 @@
+import { ConfigV1 } from "@opencode-ai/core/v1/config/config"
+import { SessionV1 } from "@opencode-ai/core/v1/session"
+import { FSUtil } from "@opencode-ai/core/fs-util"
+import { ModelsDev } from "@opencode-ai/core/models-dev"
+import { HttpRecorder } from "@opencode-ai/http-recorder"
+import { HttpRecorderInternal } from "@opencode-ai/http-recorder/internal"
+import { describe, expect, test } from "bun:test"
+import { tool, type ModelMessage, type JSONValue } from "ai"
+import { Effect, Layer, Option, Schema, Stream } from "effect"
+import path from "node:path"
+import z from "zod"
+import { Auth } from "@/auth"
+import { Config } from "@/config/config"
+import { Plugin } from "@/plugin"
+import { Provider } from "@/provider/provider"
+
+import { Filesystem } from "@/util/filesystem"
+import { LLMEvent, LLMResponse } from "@opencode-ai/llm"
+import { LLMClient, RequestExecutor, WebSocketExecutor } from "@opencode-ai/llm/route"
+import { Env } from "@/env"
+import { RuntimeFlags } from "@/effect/runtime-flags"
+import type { Agent } from "../../src/agent/agent"
+import { LLM } from "../../src/session/llm"
+import { MessageID, SessionID } from "../../src/session/schema"
+import { TestInstance } from "../fixture/fixture"
+import { testEffect } from "../lib/effect"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { ModelV2 } from "@opencode-ai/core/model"
+
+const FIXTURES_DIR = path.join(import.meta.dir, "../fixtures/recordings")
+
+const zenURL = (connection: string) => `https://console.opencode.ai/proxy/connections/${connection}/v1`
+
+const replayOpenAIOAuth = {
+  type: "oauth",
+  refresh: "fixture-refresh-token",
+  access: "fixture-access-token",
+  expires: Date.now() + 60 * 60 * 1000,
+  accountId: "fixture-account",
+} satisfies Auth.Info
+
+type RecordedScenario = {
+  readonly id: string
+  readonly name: string
+  readonly providerID: ProviderV2.ID
+  readonly modelID: string
+  readonly cassette: string
+  readonly protocol: string
+  readonly tags: ReadonlyArray<string>
+  readonly canRecord: () => boolean
+  readonly recordAuth?: () => Auth.Info | undefined
+  readonly replayAuth?: Auth.Info
+  readonly stableID?: string
+  readonly config: (model: ModelsDev.Provider["models"][string]) => Partial<ConfigV1.Info>
+}
+
+const cloneModel = (model: ModelsDev.Provider["models"][string]) => {
+  const cloned = structuredClone(model)
+  const { experimental, ...rest } = cloned
+  // oxlint-disable-next-line typescript-eslint/no-unsafe-type-assertion -- The config schema accepts the same model shape except object-valued experimental metadata.
+  if (typeof experimental === "boolean") {
+    // oxlint-disable-next-line typescript-eslint/no-unsafe-type-assertion -- The fixture model already matches config input when experimental is boolean.
+    return cloned as NonNullable<NonNullable<ConfigV1.Info["provider"]>[string]["models"]>[string]
+  }
+  // oxlint-disable-next-line typescript-eslint/no-unsafe-type-assertion -- Dropping non-boolean experimental metadata makes the fixture model match config input.
+  return rest as NonNullable<NonNullable<ConfigV1.Info["provider"]>[string]["models"]>[string]
+}
+
+const envValue = (...names: string[]) => names.map((name) => process.env[name]).find(Boolean)
+const decodeAuth = Schema.decodeUnknownOption(Auth.Info)
+const recordOpenAIOAuth = (() => {
+  let loaded = false
+  let auth: Auth.Info | undefined
+  return () => {
+    if (loaded) return auth
+    loaded = true
+    auth = decodeRecordOpenAIOAuth()
+    return auth
+  }
+})()
+
+function decodeRecordOpenAIOAuth() {
+  const value = process.env.OPENCODE_RECORD_OPENAI_AUTH
+  if (!value) return undefined
+  try {
+    const auth = Option.getOrUndefined(decodeAuth(JSON.parse(value)))
+    return auth?.type === "oauth" ? auth : undefined
+  } catch {
+    return undefined
+  }
+}
+
+const providerConfig = (input: {
+  readonly providerID: ProviderV2.ID
+  readonly name: string
+  readonly env: string[]
+  readonly npm: string
+  readonly api: string
+  readonly model: ModelsDev.Provider["models"][string]
+  readonly options: Record<string, unknown>
+}): Partial<ConfigV1.Info> => ({
+  enabled_providers: [input.providerID],
+  provider: {
+    [input.providerID]: {
+      name: input.name,
+      env: input.env,
+      npm: input.npm,
+      api: input.api,
+      models: { [input.model.id]: cloneModel(input.model) },
+      options: input.options,
+    },
+  },
+})
+
+const RECORDED_SCENARIOS = [
+  {
+    id: "openai-api-key",
+    name: "OpenAI API key",
+    providerID: ProviderV2.ID.openai,
+    modelID: "gpt-4.1-mini",
+    cassette: "session/native-openai-tool-loop",
+    protocol: "openai-responses",
+    tags: ["opencode", "native", "tool-loop"],
+    canRecord: () => Boolean(envValue("OPENCODE_RECORD_OPENAI_API_KEY", "OPENAI_API_KEY")),
+    config: (model) =>
+      providerConfig({
+        providerID: ProviderV2.ID.openai,
+        name: "OpenAI",
+        env: ["OPENAI_API_KEY"],
+        npm: "@ai-sdk/openai",
+        api: "https://api.openai.com/v1",
+        model,
+        options: {
+          apiKey: envValue("OPENCODE_RECORD_OPENAI_API_KEY", "OPENAI_API_KEY") ?? "fixture-openai-key",
+          baseURL: "https://api.openai.com/v1",
+        },
+      }),
+  },
+  {
+    id: "openai-oauth",
+    name: "OpenAI OAuth",
+    providerID: ProviderV2.ID.openai,
+    modelID: "gpt-5.5",
+    cassette: "session/native-openai-oauth-tool-loop",
+    protocol: "openai-responses",
+    tags: ["opencode", "native", "oauth", "tool-loop"],
+    canRecord: () => recordOpenAIOAuth() !== undefined,
+    recordAuth: recordOpenAIOAuth,
+    replayAuth: replayOpenAIOAuth,
+    stableID: "openai-oauth",
+    config: (model) =>
+      providerConfig({
+        providerID: ProviderV2.ID.openai,
+        name: "OpenAI",
+        env: ["OPENAI_API_KEY"],
+        npm: "@ai-sdk/openai",
+        api: "https://api.openai.com/v1",
+        model,
+        options: { baseURL: "https://api.openai.com/v1" },
+      }),
+  },
+  {
+    id: "opencode-proxy",
+    name: "OpenCode proxy",
+    providerID: ProviderV2.ID.opencode,
+    modelID: "gpt-5.2-codex",
+    cassette: "session/native-zen-tool-loop",
+    protocol: "openai-responses",
+    tags: ["opencode", "zen", "native", "tool-loop"],
+    canRecord: () => Boolean(process.env.OPENCODE_RECORD_CONSOLE_TOKEN && process.env.OPENCODE_RECORD_ZEN_ORG_ID),
+    config: (model) =>
+      providerConfig({
+        providerID: ProviderV2.ID.opencode,
+        name: "OpenCode Zen",
+        env: ["OPENCODE_CONSOLE_TOKEN"],
+        npm: "@ai-sdk/openai-compatible",
+        api: zenURL(process.env.OPENCODE_RECORD_ZEN_CONNECTION ?? "fixture"),
+        model,
+        options: {
+          apiKey: process.env.OPENCODE_RECORD_CONSOLE_TOKEN ?? "fixture-console-token",
+          headers: { "x-org-id": process.env.OPENCODE_RECORD_ZEN_ORG_ID ?? "fixture-org" },
+        },
+      }),
+  },
+  {
+    id: "anthropic-api-key",
+    name: "Anthropic API key",
+    providerID: ProviderV2.ID.anthropic,
+    modelID: "claude-haiku-4-5-20251001",
+    cassette: "session/native-anthropic-tool-loop",
+    protocol: "anthropic-messages",
+    tags: ["opencode", "native", "tool-loop"],
+    canRecord: () => Boolean(envValue("OPENCODE_RECORD_ANTHROPIC_API_KEY", "ANTHROPIC_API_KEY")),
+    config: (model) =>
+      providerConfig({
+        providerID: ProviderV2.ID.anthropic,
+        name: "Anthropic",
+        env: ["ANTHROPIC_API_KEY"],
+        npm: "@ai-sdk/anthropic",
+        api: "https://api.anthropic.com/v1",
+        model,
+        options: {
+          apiKey: envValue("OPENCODE_RECORD_ANTHROPIC_API_KEY", "ANTHROPIC_API_KEY") ?? "fixture-anthropic-key",
+          baseURL: "https://api.anthropic.com/v1",
+        },
+      }),
+  },
+] satisfies ReadonlyArray<RecordedScenario>
+
+const shouldRecord = process.env.RECORD === "true"
+const selectedScenarios = new Set(
+  (envValue("OPENCODE_RECORDED_SCENARIO", "RECORDED_PROVIDER") ?? "")
+    .split(",")
+    .map((item) => item.trim().toLowerCase())
+    .filter(Boolean),
+)
+
+function isSelected(scenario: RecordedScenario) {
+  if (selectedScenarios.size === 0) return true
+  return [scenario.id, scenario.name, scenario.providerID, scenario.cassette, ...scenario.tags]
+    .map((item) => item.toLowerCase())
+    .some((item) => selectedScenarios.has(item))
+}
+
+const canRun = (scenario: RecordedScenario) =>
+  shouldRecord
+    ? scenario.canRecord()
+    : HttpRecorderInternal.hasCassetteSync(scenario.cassette, { directory: FIXTURES_DIR })
+
+const recordError = (scenario: RecordedScenario) =>
+  scenario.id === "openai-oauth"
+    ? "Set OPENCODE_RECORD_OPENAI_AUTH to an OAuth auth JSON object in the recording environment."
+    : `Missing recording credentials for ${scenario.name}.`
+
+const redactRecordedBody = (body: string) =>
+  body
+    .replace(/wrk_[A-Z0-9]+/g, "wrk_redacted")
+    .replace(/"safety_identifier"\s*:\s*"user-[^"]+"/g, '"safety_identifier":"user_redacted"')
+    .replace(/"(access|access_token|refresh|refresh_token|accountId|account_id)"\s*:\s*"[^"]+"/g, '"$1":"redacted"')
+
+function authLayer(scenario: RecordedScenario) {
+  const replayAuth = shouldRecord ? scenario.recordAuth?.() : scenario.replayAuth
+  if (!replayAuth) return Auth.defaultLayer
+  return Layer.mock(Auth.Service)({
+    get: (providerID) => Effect.succeed(providerID === scenario.providerID ? replayAuth : undefined),
+    all: () => Effect.succeed({ [scenario.providerID]: replayAuth }),
+  })
+}
+
+async function loadFixture(providerID: string, modelID: string) {
+  const data = await modelsFixture
+  const provider = data[providerID]
+  if (!provider) throw new Error(`Missing provider in fixture: ${providerID}`)
+  const model = provider.models[modelID]
+  if (!model) throw new Error(`Missing model in fixture: ${modelID}`)
+  return model
+}
+
+const modelsFixture = Filesystem.readJson<Record<string, ModelsDev.Provider>>(
+  path.join(import.meta.dir, "../tool/fixtures/models-api.json"),
+)
+
+function recordedNativeLLMLayer(scenario: RecordedScenario) {
+  const auth = authLayer(scenario)
+  const provider = Provider.layer.pipe(
+    Layer.provide(FSUtil.defaultLayer),
+    Layer.provide(Env.defaultLayer),
+    Layer.provide(Config.defaultLayer),
+    Layer.provide(auth),
+    Layer.provide(Plugin.defaultLayer),
+    Layer.provide(ModelsDev.defaultLayer),
+    Layer.provide(RuntimeFlags.defaultLayer),
+  )
+  // Only the HTTP client is recorded; RequestExecutor and the opencode LLM stack remain real.
+  const metadata = {
+    provider: scenario.providerID,
+    protocol: scenario.protocol,
+    route: scenario.protocol,
+    tags: scenario.tags,
+  }
+  const redact = {
+    url: (url: string) => url.replace(/\/proxy\/connections\/[^/]+\/v1/, "/proxy/connections/{connection}/v1"),
+    body: redactRecordedBody,
+  }
+  const recordedHttp = shouldRecord
+    ? HttpRecorderInternal.cassetteLayer(scenario.cassette, {
+        directory: FIXTURES_DIR,
+        mode: "record",
+        metadata,
+        redactor: HttpRecorderInternal.Redactor.make(redact),
+      })
+    : HttpRecorder.http(scenario.cassette, { directory: FIXTURES_DIR, metadata, redact })
+  const recordedClient = LLMClient.layer.pipe(
+    Layer.provide(Layer.mergeAll(RequestExecutor.layer.pipe(Layer.provide(recordedHttp)), WebSocketExecutor.layer)),
+  )
+
+  return Layer.mergeAll(
+    provider,
+    LLM.layer.pipe(
+      Layer.provide(auth),
+      Layer.provide(Config.defaultLayer),
+      Layer.provide(provider),
+      Layer.provide(Plugin.defaultLayer),
+      Layer.provide(recordedClient),
+      Layer.provide(RuntimeFlags.layer({ experimentalNativeLlm: true })),
+    ),
+  )
+}
+
+const writeConfig = (directory: string, scenario: RecordedScenario, model: ModelsDev.Provider["models"][string]) =>
+  Effect.promise(() =>
+    Bun.write(
+      path.join(directory, "opencode.json"),
+      JSON.stringify({ $schema: "https://opencode.ai/config.json", ...scenario.config(model) }),
+    ),
+  )
+
+const collect = (input: LLM.StreamInput) =>
+  Effect.gen(function* () {
+    const llm = yield* LLM.Service
+    return Array.from(yield* llm.stream(input).pipe(Stream.runCollect))
+  })
+
+const WEATHER_RESULT = { temperature: 22, condition: "sunny" } as const
+const WEATHER_SYSTEM =
+  "Use the get_weather tool exactly once to look up Paris, then reply with exactly: Paris is sunny."
+const WEATHER_USER = "What is the weather in Paris?"
+
+const weatherTool = tool({
+  description: "Get the current weather for a city.",
+  inputSchema: z.object({ city: z.string() }),
+  execute: async () => WEATHER_RESULT,
+})
+
+const toolRoundtrip = (
+  events: ReadonlyArray<LLMEvent>,
+  call: { readonly id: string; readonly name: string; readonly input: unknown },
+  result: JSONValue,
+): ModelMessage[] => [
+  {
+    role: "assistant",
+    content: [
+      ...events.filter(LLMEvent.is.reasoningEnd).map((part) => ({
+        type: "reasoning" as const,
+        text: events
+          .filter(LLMEvent.is.reasoningDelta)
+          .filter((event) => event.id === part.id)
+          .map((event) => event.text)
+          .join(""),
+        providerMetadata: part.providerMetadata,
+      })),
+      { type: "tool-call", toolCallId: call.id, toolName: call.name, input: call.input },
+    ],
+  },
+  {
+    role: "tool",
+    content: [
+      { type: "tool-result", toolCallId: call.id, toolName: call.name, output: { type: "json", value: result } },
+    ],
+  },
+]
+
+const driveToolLoop = (scenario: RecordedScenario) =>
+  Effect.gen(function* () {
+    const test = yield* TestInstance
+    const model = yield* Effect.promise(() => loadFixture(scenario.providerID, scenario.modelID))
+    yield* writeConfig(test.directory, scenario, model)
+
+    const stableID = scenario.stableID ?? scenario.providerID
+    const sessionID = SessionID.make(`session-recorded-${stableID}-loop`)
+    const modelID = ModelV2.ID.make(model.id)
+    const agent = {
+      name: "test",
+      mode: "primary",
+      prompt: "Answer using tools when appropriate.",
+      options: {},
+      permission: [{ permission: "*", pattern: "*", action: "allow" }],
+      temperature: 0,
+    } satisfies Agent.Info
+    const provider = yield* Provider.Service
+    const resolved = yield* provider.getModel(scenario.providerID, modelID)
+
+    const userMessage = { role: "user", content: WEATHER_USER } satisfies ModelMessage
+    const base = {
+      user: {
+        id: MessageID.make(`msg_user-recorded-${stableID}-loop`),
+        sessionID,
+        role: "user",
+        time: { created: 0 },
+        agent: agent.name,
+        model: { providerID: scenario.providerID, modelID },
+      } satisfies SessionV1.User,
+      sessionID,
+      model: resolved,
+      agent,
+      system: [WEATHER_SYSTEM],
+      tools: { get_weather: weatherTool },
+    }
+
+    const turn1 = yield* collect({ ...base, messages: [userMessage] })
+    const toolCall = turn1.find(LLMEvent.is.toolCall)
+    expect(toolCall).toBeDefined()
+    expect(turn1.find(LLMEvent.is.toolResult)).toBeDefined()
+    expect(toolCall!.name).toBe("get_weather")
+    expect(toolCall!.input).toMatchObject({ city: expect.stringMatching(/Paris/i) })
+    expect(turn1.filter(LLMEvent.is.stepFinish)).toHaveLength(1)
+
+    const turn2 = yield* collect({
+      ...base,
+      messages: [userMessage, ...toolRoundtrip(turn1, toolCall!, WEATHER_RESULT)],
+    })
+
+    expect(LLMResponse.text({ events: turn2 })).toMatch(/Paris is sunny/i)
+    expect(turn2.filter(LLMEvent.is.finish)).toHaveLength(1)
+    expect(turn2.filter(LLMEvent.is.toolCall)).toHaveLength(0)
+  })
+
+describe("session.llm native recorded", () => {
+  for (const scenario of RECORDED_SCENARIOS.filter(isSelected)) {
+    if (!canRun(scenario)) {
+      if (shouldRecord && scenario.recordAuth && selectedScenarios.size > 0) {
+        test(`${scenario.name}: drives a tool loop to a final text answer`, () => {
+          throw new Error(recordError(scenario))
+        })
+        continue
+      }
+      test.skip(`${scenario.name}: drives a tool loop to a final text answer`, () => {})
+      continue
+    }
+    const it = testEffect(recordedNativeLLMLayer(scenario))
+    it.instance(`${scenario.name}: drives a tool loop to a final text answer`, () => driveToolLoop(scenario))
+  }
+})

packages/opencode/test/session/llm-native.test.ts

@@ -0,0 +1,760 @@
+import { describe, expect, test } from "bun:test"
+import { LLMEvent, ToolFailure } from "@opencode-ai/llm"
+import { LLMClient, RequestExecutor, WebSocketExecutor, type LLMClientShape } from "@opencode-ai/llm/route"
+import { jsonSchema, tool, type ModelMessage, type Tool } from "ai"
+import { Effect, Fiber, Layer, Stream } from "effect"
+import { LLMNative } from "@/session/llm/native-request"
+import { LLMNativeRuntime } from "@/session/llm/native-runtime"
+import type { Provider } from "@/provider/provider"
+
+import { OAUTH_DUMMY_KEY } from "@/auth"
+import { testEffect } from "../lib/effect"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { ModelV2 } from "@opencode-ai/core/model"
+
+const baseModel: Provider.Model = {
+  id: ModelV2.ID.make("gpt-5-mini"),
+  providerID: ProviderV2.ID.make("openai"),
+  api: {
+    id: "gpt-5-mini",
+    url: "https://api.openai.com/v1",
+    npm: "@ai-sdk/openai",
+  },
+  name: "GPT-5 Mini",
+  capabilities: {
+    temperature: true,
+    reasoning: true,
+    attachment: true,
+    toolcall: true,
+    input: {
+      text: true,
+      audio: false,
+      image: true,
+      video: false,
+      pdf: false,
+    },
+    output: {
+      text: true,
+      audio: false,
+      image: false,
+      video: false,
+      pdf: false,
+    },
+    interleaved: false,
+  },
+  cost: {
+    input: 0,
+    output: 0,
+    cache: {
+      read: 0,
+      write: 0,
+    },
+  },
+  limit: {
+    context: 128_000,
+    input: 128_000,
+    output: 32_000,
+  },
+  status: "active",
+  options: {},
+  headers: {
+    "x-model": "model-header",
+  },
+  release_date: "2026-01-01",
+}
+
+const providerInfo: Provider.Info = {
+  id: ProviderV2.ID.make("openai"),
+  name: "OpenAI",
+  source: "config",
+  env: ["OPENAI_API_KEY"],
+  options: { apiKey: "test-openai-key" },
+  models: {},
+}
+
+const it = testEffect(
+  LLMClient.layer.pipe(Layer.provide(Layer.mergeAll(RequestExecutor.defaultLayer, WebSocketExecutor.layer))),
+)
+
+function responsesStream(chunks: unknown[]) {
+  return new Response(chunks.map((chunk) => `data: ${JSON.stringify(chunk)}`).join("\n\n") + "\n\n", {
+    status: 200,
+    headers: { "Content-Type": "text/event-stream" },
+  })
+}
+
+type NativeRequestInput = Parameters<typeof LLMNative.request>[0]
+
+const sessionText = (text: string) => ({ type: "text" as const, text })
+
+const sessionOpenAIReasoning = (
+  text: string,
+  options: {
+    readonly storedAs: "providerMetadata" | "providerOptions"
+    readonly itemId: string
+    readonly encryptedContent: string | null
+  },
+) => {
+  const metadata = {
+    openai: { itemId: options.itemId, reasoningEncryptedContent: options.encryptedContent },
+  }
+  if (options.storedAs === "providerMetadata")
+    return Object.assign({ type: "reasoning" as const, text }, { providerMetadata: metadata })
+  return Object.assign({ type: "reasoning" as const, text }, { providerOptions: metadata })
+}
+
+type SessionAssistantPart = ReturnType<typeof sessionText> | ReturnType<typeof sessionOpenAIReasoning>
+
+const storedSession = {
+  user: (content: string): ModelMessage => ({ role: "user", content }),
+  assistant: (content: SessionAssistantPart[]): ModelMessage => ({ role: "assistant", content }),
+  text: sessionText,
+  openaiReasoning: sessionOpenAIReasoning,
+}
+
+const openAIResponses = {
+  user: (text: string) => ({ role: "user", content: [{ type: "input_text", text }] }),
+  assistant: (text: string) => ({ role: "assistant", content: [{ type: "output_text", text }] }),
+  openaiReasoning: (text: string, options: { readonly itemId: string; readonly encryptedContent: string }) => ({
+    type: "reasoning",
+    id: options.itemId,
+    encrypted_content: options.encryptedContent,
+    summary: [{ type: "summary_text", text }],
+  }),
+}
+
+const prepareNativeRequest = (input: NativeRequestInput) => LLMClient.prepare(LLMNative.request(input))
+
+const expectOpenAIResponsesRequest = (input: {
+  readonly history: NativeRequestInput["messages"]
+  readonly providerOptions?: NativeRequestInput["providerOptions"]
+  readonly maxOutputTokens?: NativeRequestInput["maxOutputTokens"]
+  readonly headers?: NativeRequestInput["headers"]
+  readonly expectedBody: unknown
+}) =>
+  Effect.gen(function* () {
+    expect(
+      yield* prepareNativeRequest({
+        model: baseModel,
+        apiKey: "test-openai-key",
+        messages: input.history,
+        providerOptions: input.providerOptions,
+        maxOutputTokens: input.maxOutputTokens,
+        headers: input.headers,
+      }),
+    ).toMatchObject({
+      route: "openai-responses",
+      protocol: "openai-responses",
+      body: input.expectedBody,
+    })
+  })
+
+describe("session.llm-native.request", () => {
+  test("maps normalized stream inputs to a native LLM request", () => {
+    const messages: ModelMessage[] = [
+      {
+        role: "system",
+        content: "system from messages",
+      },
+      {
+        role: "user",
+        content: [
+          { type: "text", text: "hello", providerOptions: { openai: { cacheControl: { type: "ephemeral" } } } },
+          { type: "file", mediaType: "image/png", filename: "img.png", data: "data:image/png;base64,Zm9v" },
+        ],
+      },
+      {
+        role: "assistant",
+        content: [
+          { type: "reasoning", text: "thinking", providerOptions: { openai: { encryptedContent: "secret" } } },
+          { type: "text", text: "I'll run it" },
+          {
+            type: "tool-call",
+            toolCallId: "call-1",
+            toolName: "bash",
+            input: { command: "ls" },
+            providerOptions: { openai: { itemId: "item-1" } },
+          },
+        ],
+      },
+      {
+        role: "tool",
+        content: [
+          {
+            type: "tool-result",
+            toolCallId: "call-1",
+            toolName: "bash",
+            output: { type: "text", value: "ok" },
+            providerOptions: { openai: { outputId: "output-1" } },
+          },
+        ],
+      },
+    ]
+
+    const request = LLMNative.request({
+      model: baseModel,
+      system: ["agent system"],
+      messages,
+      tools: {
+        bash: tool({
+          description: "Run a shell command",
+          inputSchema: jsonSchema({
+            type: "object",
+            properties: {
+              command: { type: "string" },
+            },
+            required: ["command"],
+          }),
+        }),
+      },
+      toolChoice: "required",
+      temperature: 0.2,
+      topP: 0.9,
+      topK: 40,
+      maxOutputTokens: 1024,
+      providerOptions: { openai: { store: false } },
+      headers: { "x-request": "request-header" },
+    })
+
+    expect(request.model).toMatchObject({
+      id: "gpt-5-mini",
+      provider: "openai",
+      route: { id: "openai-responses" },
+    })
+    expect(request.model.route.endpoint.baseURL).toBe("https://api.openai.com/v1")
+    expect(request.model.route.defaults.headers).toEqual({
+      "x-model": "model-header",
+      "x-request": "request-header",
+    })
+    expect(request.model.route.defaults.limits).toMatchObject({
+      context: 128_000,
+      output: 32_000,
+    })
+    expect(request.system).toEqual([
+      { type: "text", text: "agent system" },
+      { type: "text", text: "system from messages" },
+    ])
+    expect(request.generation).toMatchObject({
+      temperature: 0.2,
+      topP: 0.9,
+      topK: 40,
+      maxTokens: 1024,
+    })
+    expect(request.providerOptions).toEqual({ openai: { store: false } })
+    expect(request.toolChoice).toMatchObject({ type: "required" })
+    expect(request.tools).toMatchObject([
+      {
+        name: "bash",
+        description: "Run a shell command",
+        inputSchema: {
+          type: "object",
+          properties: {
+            command: { type: "string" },
+          },
+          required: ["command"],
+        },
+      },
+    ])
+    expect(request.messages).toMatchObject([
+      {
+        role: "user",
+        content: [
+          { type: "text", text: "hello", providerMetadata: { openai: { cacheControl: { type: "ephemeral" } } } },
+          { type: "media", mediaType: "image/png", filename: "img.png", data: "data:image/png;base64,Zm9v" },
+        ],
+      },
+      {
+        role: "assistant",
+        content: [
+          { type: "reasoning", text: "thinking", providerMetadata: { openai: { encryptedContent: "secret" } } },
+          { type: "text", text: "I'll run it" },
+          {
+            type: "tool-call",
+            id: "call-1",
+            name: "bash",
+            input: { command: "ls" },
+            providerMetadata: { openai: { itemId: "item-1" } },
+          },
+        ],
+      },
+      {
+        role: "tool",
+        content: [
+          {
+            type: "tool-result",
+            id: "call-1",
+            name: "bash",
+            result: { type: "text", value: "ok" },
+            providerMetadata: { openai: { outputId: "output-1" } },
+          },
+        ],
+      },
+    ])
+  })
+
+  test("maps stored provider metadata to native content metadata", () => {
+    const reasoning = Object.assign(
+      { type: "reasoning" as const, text: "thinking" },
+      {
+        providerMetadata: {
+          openai: {
+            itemId: "rs_1",
+            reasoningEncryptedContent: "encrypted-state",
+          },
+        },
+      },
+    )
+    const request = LLMNative.request({
+      model: baseModel,
+      messages: [
+        {
+          role: "assistant",
+          content: [reasoning],
+        },
+      ],
+    })
+
+    expect(request.messages).toMatchObject([
+      {
+        role: "assistant",
+        content: [
+          {
+            type: "reasoning",
+            text: "thinking",
+            providerMetadata: { openai: { itemId: "rs_1", reasoningEncryptedContent: "encrypted-state" } },
+          },
+        ],
+      },
+    ])
+  })
+
+  test("selects native request routes for provider packages", () => {
+    const openai = LLMNative.model({
+      model: { ...baseModel, api: { ...baseModel.api, url: "", npm: "@ai-sdk/openai" } },
+      apiKey: "test-key",
+      messages: [],
+    })
+    expect(openai.route.id).toBe("openai-responses")
+    expect(openai.route.endpoint.baseURL).toBe("https://api.openai.com/v1")
+
+    const anthropic = LLMNative.model({
+      model: { ...baseModel, api: { ...baseModel.api, url: "", npm: "@ai-sdk/anthropic" } },
+      apiKey: "test-key",
+      messages: [],
+    })
+    expect(anthropic.route.id).toBe("anthropic-messages")
+    expect(anthropic.route.endpoint.baseURL).toBe("https://api.anthropic.com/v1")
+
+    const google = LLMNative.model({
+      model: { ...baseModel, api: { ...baseModel.api, url: "", npm: "@ai-sdk/google" } },
+      apiKey: "test-key",
+      messages: [],
+    })
+    expect(google.route.id).toBe("gemini")
+    expect(google.route.endpoint.baseURL).toBe("https://generativelanguage.googleapis.com/v1beta")
+
+    const compatible = LLMNative.model({
+      model: {
+        ...baseModel,
+        providerID: ProviderV2.ID.make("opencode"),
+        api: { ...baseModel.api, url: "https://ai.example.test/v1", npm: "@ai-sdk/openai-compatible" },
+      },
+      apiKey: "test-key",
+      messages: [],
+    })
+    expect(compatible.route.id).toBe("openai-compatible-chat")
+    expect(compatible.route.endpoint.baseURL).toBe("https://ai.example.test/v1")
+
+    const openrouter = LLMNative.model({
+      model: { ...baseModel, api: { ...baseModel.api, url: "", npm: "@openrouter/ai-sdk-provider" } },
+      apiKey: "test-key",
+      messages: [],
+    })
+    expect(openrouter.route.id).toBe("openrouter")
+    expect(openrouter.route.endpoint.baseURL).toBe("https://openrouter.ai/api/v1")
+  })
+
+  test("fails fast for unsupported provider packages", () => {
+    expect(() =>
+      LLMNative.request({
+        model: { ...baseModel, api: { ...baseModel.api, npm: "unknown-provider" } },
+        messages: [],
+      }),
+    ).toThrow("Native LLM request adapter does not support provider package unknown-provider")
+  })
+
+  test("only enables native runtime for supported OpenAI API-key models", () => {
+    expect(LLMNativeRuntime.status({ model: baseModel, provider: providerInfo, auth: undefined })).toMatchObject({
+      type: "supported",
+      apiKey: "test-openai-key",
+    })
+    expect(
+      LLMNativeRuntime.status({
+        model: { ...baseModel, providerID: ProviderV2.ID.make("opencode") },
+        provider: { ...providerInfo, id: ProviderV2.ID.make("opencode") },
+        auth: undefined,
+      }),
+    ).toMatchObject({
+      type: "supported",
+      apiKey: "test-openai-key",
+    })
+    expect(
+      LLMNativeRuntime.status({
+        model: {
+          ...baseModel,
+          providerID: ProviderV2.ID.make("opencode"),
+          api: { ...baseModel.api, npm: "@ai-sdk/openai-compatible" },
+        },
+        provider: { ...providerInfo, id: ProviderV2.ID.make("opencode") },
+        auth: undefined,
+      }),
+    ).toMatchObject({
+      type: "supported",
+      apiKey: "test-openai-key",
+    })
+    expect(
+      LLMNativeRuntime.status({
+        model: { ...baseModel, providerID: ProviderV2.ID.make("google") },
+        provider: { ...providerInfo, id: ProviderV2.ID.make("google") },
+        auth: undefined,
+      }),
+    ).toEqual({ type: "unsupported", reason: "provider is not openai, opencode, or anthropic" })
+    expect(
+      LLMNativeRuntime.status({
+        model: baseModel,
+        provider: providerInfo,
+        auth: { type: "oauth", refresh: "refresh", access: "access", expires: 1 },
+      }),
+    ).toEqual({ type: "unsupported", reason: "OAuth auth requires a provider fetch override" })
+    expect(
+      LLMNativeRuntime.status({
+        model: baseModel,
+        provider: { ...providerInfo, options: { apiKey: OAUTH_DUMMY_KEY, fetch: async () => new Response() } },
+        auth: { type: "oauth", refresh: "refresh", access: "access", expires: 1 },
+      }),
+    ).toMatchObject({ type: "supported", apiKey: OAUTH_DUMMY_KEY })
+
+    expect(
+      LLMNativeRuntime.status({
+        model: { ...baseModel, api: { ...baseModel.api, npm: "@ai-sdk/google" } },
+        provider: providerInfo,
+        auth: undefined,
+      }),
+    ).toEqual({ type: "unsupported", reason: "provider package is not OpenAI, OpenAI-compatible, or Anthropic" })
+
+    expect(
+      LLMNativeRuntime.status({
+        model: baseModel,
+        provider: { ...providerInfo, options: {} },
+        auth: undefined,
+      }),
+    ).toEqual({ type: "unsupported", reason: "API key is not configured" })
+  })
+
+  test("enables native runtime for Anthropic API-key models", () => {
+    expect(
+      LLMNativeRuntime.status({
+        model: {
+          ...baseModel,
+          providerID: ProviderV2.ID.make("anthropic"),
+          api: { ...baseModel.api, npm: "@ai-sdk/anthropic", url: "https://api.anthropic.com/v1" },
+        },
+        provider: {
+          ...providerInfo,
+          id: ProviderV2.ID.make("anthropic"),
+          name: "Anthropic",
+          env: ["ANTHROPIC_API_KEY"],
+          options: { apiKey: "test-anthropic-key" },
+        },
+        auth: undefined,
+      }),
+    ).toMatchObject({ type: "supported", apiKey: "test-anthropic-key" })
+  })
+
+  test("prefers console provider api key over stored opencode auth", () => {
+    expect(
+      LLMNativeRuntime.status({
+        model: { ...baseModel, providerID: ProviderV2.ID.make("opencode") },
+        provider: {
+          ...providerInfo,
+          id: ProviderV2.ID.make("opencode"),
+          options: { apiKey: "console-token" },
+          key: "zen-token",
+        },
+        auth: { type: "api", key: "zen-token" },
+      }),
+    ).toMatchObject({
+      type: "supported",
+      apiKey: "console-token",
+    })
+    expect(
+      LLMNativeRuntime.status({
+        model: baseModel,
+        provider: { ...providerInfo, options: {}, key: "provider-key" },
+        auth: undefined,
+      }),
+    ).toMatchObject({
+      type: "supported",
+      apiKey: "provider-key",
+    })
+  })
+
+  it.effect("native tool wrapper converts thrown errors into typed ToolFailure", () =>
+    Effect.gen(function* () {
+      const wrapped = LLMNativeRuntime.nativeTools(
+        {
+          explode: {
+            description: "always throws",
+            inputSchema: jsonSchema({ type: "object" }),
+            execute: async () => {
+              throw new Error("boom")
+            },
+          } satisfies Tool,
+        },
+        { messages: [] as ModelMessage[], abort: new AbortController().signal },
+      )
+
+      const failure = yield* Effect.flip(wrapped.explode.execute({}, { id: "call-1", name: "explode" }))
+      expect(failure).toBeInstanceOf(ToolFailure)
+      expect(failure.message).toBe("boom")
+    }),
+  )
+
+  it.effect("native tool wrapper raises ToolFailure when the source tool has no execute handler", () =>
+    Effect.gen(function* () {
+      // The AI SDK Tool shape allows execute to be omitted (e.g., client-side / MCP tools).
+      // The native runtime owns execution, so encountering such a tool here means upstream
+      // wiring is wrong; we want a typed failure, not a silent skip or unhandled exception.
+      const wrapped = LLMNativeRuntime.nativeTools(
+        { incomplete: { description: "no execute", inputSchema: jsonSchema({ type: "object" }) } satisfies Tool },
+        { messages: [] as ModelMessage[], abort: new AbortController().signal },
+      )
+
+      const failure = yield* Effect.flip(wrapped.incomplete.execute({}, { id: "call-1", name: "incomplete" }))
+      expect(failure).toBeInstanceOf(ToolFailure)
+      expect(failure.message).toContain("incomplete")
+    }),
+  )
+
+  it.effect("emits native tool calls before overlapping local settlements complete", () =>
+    Effect.gen(function* () {
+      const observed: string[] = []
+      const started: string[] = []
+      let release: (() => void) | undefined
+      let notifyStarted: (() => void) | undefined
+      const gate = new Promise<void>((resolve) => {
+        release = resolve
+      })
+      const bothStarted = new Promise<void>((resolve) => {
+        notifyStarted = resolve
+      })
+      const lookup = {
+        description: "Lookup data",
+        inputSchema: jsonSchema({ type: "object" }),
+        execute: async (_args: unknown, options: { toolCallId: string }) => {
+          started.push(options.toolCallId)
+          if (started.length === 2) notifyStarted?.()
+          await gate
+          return { output: options.toolCallId }
+        },
+      } satisfies Tool
+      const llmClient = {
+        prepare: () => Effect.die("unused"),
+        stream: () =>
+          Stream.fromIterable([
+            LLMEvent.toolCall({ id: "call-1", name: "lookup", input: {} }),
+            LLMEvent.toolCall({ id: "call-2", name: "lookup", input: {} }),
+            LLMEvent.finish({ reason: "tool-calls" }),
+          ]),
+        generate: () => Effect.die("unused"),
+      } as LLMClientShape
+      const native = LLMNativeRuntime.stream({
+        model: baseModel,
+        provider: providerInfo,
+        auth: undefined,
+        llmClient,
+        messages: [],
+        tools: { lookup },
+        headers: {},
+        abort: new AbortController().signal,
+      })
+      expect(native.type).toBe("supported")
+      if (native.type === "unsupported") throw new Error(native.reason)
+
+      const fiber = yield* native.stream.pipe(
+        Stream.runForEach((event) => Effect.sync(() => observed.push(event.type))),
+        Effect.forkScoped,
+      )
+      yield* Effect.promise(() => bothStarted)
+
+      expect(started).toEqual(["call-1", "call-2"])
+      expect(observed).toEqual(["tool-call", "tool-call", "finish"])
+
+      release?.()
+      yield* Fiber.join(fiber)
+      expect(observed).toEqual(["tool-call", "tool-call", "finish", "tool-result", "tool-result"])
+    }),
+  )
+
+  it.effect("compiles through the native OpenAI Responses route", () =>
+    expectOpenAIResponsesRequest({
+      history: [storedSession.user("hello")],
+      providerOptions: { openai: { store: false, instructions: "You are concise." } },
+      maxOutputTokens: 512,
+      headers: { "x-request": "request-header" },
+      expectedBody: {
+        model: "gpt-5-mini",
+        instructions: "You are concise.",
+        input: [openAIResponses.user("hello")],
+        max_output_tokens: 512,
+        store: false,
+        stream: true,
+      },
+    }),
+  )
+
+  it.effect("omits non-persisted OpenAI reasoning ids without encrypted state", () =>
+    expectOpenAIResponsesRequest({
+      history: [
+        storedSession.user("What changed?"),
+        storedSession.assistant([
+          storedSession.openaiReasoning("Checked the previous diff.", {
+            storedAs: "providerOptions",
+            itemId: "rs_1",
+            encryptedContent: null,
+          }),
+          storedSession.text("The parser changed."),
+        ]),
+        storedSession.user("Summarize it."),
+      ],
+      providerOptions: { openai: { store: false } },
+      expectedBody: {
+        input: [
+          openAIResponses.user("What changed?"),
+          openAIResponses.assistant("The parser changed."),
+          openAIResponses.user("Summarize it."),
+        ],
+        store: false,
+      },
+    }),
+  )
+
+  it.effect("preserves encrypted OpenAI reasoning state through native request lowering", () =>
+    expectOpenAIResponsesRequest({
+      history: [
+        storedSession.user("What changed?"),
+        storedSession.assistant([
+          storedSession.openaiReasoning("Checked the previous diff.", {
+            storedAs: "providerMetadata",
+            itemId: "rs_1",
+            encryptedContent: "encrypted-state",
+          }),
+          storedSession.text("The parser changed."),
+        ]),
+        storedSession.user("Summarize it."),
+      ],
+      providerOptions: { openai: { store: false, include: ["reasoning.encrypted_content"] } },
+      expectedBody: {
+        input: [
+          openAIResponses.user("What changed?"),
+          openAIResponses.openaiReasoning("Checked the previous diff.", {
+            itemId: "rs_1",
+            encryptedContent: "encrypted-state",
+          }),
+          openAIResponses.assistant("The parser changed."),
+          openAIResponses.user("Summarize it."),
+        ],
+        include: ["reasoning.encrypted_content"],
+        store: false,
+      },
+    }),
+  )
+
+  it.effect("preserves empty encrypted OpenAI reasoning items before tool output", () =>
+    expectOpenAIResponsesRequest({
+      history: [
+        storedSession.assistant([
+          storedSession.openaiReasoning("", {
+            storedAs: "providerMetadata",
+            itemId: "rs_1",
+            encryptedContent: "encrypted-state",
+          }),
+        ]),
+      ],
+      providerOptions: { openai: { store: false, include: ["reasoning.encrypted_content"] } },
+      expectedBody: {
+        input: [{ type: "reasoning", id: "rs_1", summary: [], encrypted_content: "encrypted-state" }],
+        include: ["reasoning.encrypted_content"],
+        store: false,
+      },
+    }),
+  )
+
+  it.effect("references stored OpenAI reasoning items by id", () =>
+    expectOpenAIResponsesRequest({
+      history: [
+        storedSession.assistant([
+          storedSession.openaiReasoning("Checked the previous diff.", {
+            storedAs: "providerMetadata",
+            itemId: "rs_1",
+            encryptedContent: null,
+          }),
+        ]),
+      ],
+      providerOptions: { openai: { store: true } },
+      expectedBody: {
+        input: [{ type: "item_reference", id: "rs_1" }],
+        store: true,
+      },
+    }),
+  )
+
+  it.effect("uses provider fetch override for native OpenAI OAuth requests", () =>
+    Effect.gen(function* () {
+      const captures: Array<{ url: string; body: unknown }> = []
+      const customFetch = Object.assign(
+        async (input: Parameters<typeof fetch>[0], init: Parameters<typeof fetch>[1]) => {
+          const request = input instanceof Request ? input : new Request(input, init)
+          captures.push({ url: request.url, body: await request.clone().json() })
+          return responsesStream([
+            { type: "response.output_text.delta", item_id: "msg_1", delta: "Hello" },
+            { type: "response.completed", response: { usage: { input_tokens: 1, output_tokens: 1 } } },
+          ])
+        },
+        { preconnect: () => undefined },
+      ) satisfies typeof fetch
+
+      const llmClient = yield* LLMClient.Service
+      const native = LLMNativeRuntime.stream({
+        model: baseModel,
+        provider: { ...providerInfo, options: { apiKey: OAUTH_DUMMY_KEY, fetch: customFetch } },
+        auth: { type: "oauth", refresh: "refresh", access: "access", expires: Date.now() + 60_000 },
+        llmClient,
+        messages: [{ role: "user", content: "hello" }],
+        tools: {},
+        providerOptions: { instructions: "You are concise." },
+        headers: {},
+        abort: new AbortController().signal,
+      })
+      expect(native.type).toBe("supported")
+      if (native.type === "unsupported") throw new Error(native.reason)
+      const events = Array.from(yield* native.stream.pipe(Stream.runCollect))
+
+      expect(captures).toHaveLength(1)
+      expect(captures[0]).toMatchObject({
+        url: "https://api.openai.com/v1/responses",
+        body: {
+          model: "gpt-5-mini",
+          instructions: "You are concise.",
+          input: [{ role: "user", content: [{ type: "input_text", text: "hello" }] }],
+        },
+      })
+      expect(events).toEqual(
+        expect.arrayContaining([
+          expect.objectContaining({ type: "text-delta", text: "Hello" }),
+          expect.objectContaining({ type: "finish" }),
+        ]),
+      )
+    }),
+  )
+})

packages/opencode/test/session/retry.test.ts

@@ -0,0 +1,439 @@
+import { describe, expect, test } from "bun:test"
+import { SessionV1 } from "@opencode-ai/core/v1/session"
+import type { NamedError } from "@opencode-ai/core/util/error"
+import { APICallError } from "ai"
+import { setTimeout as sleep } from "node:timers/promises"
+import { Effect, Layer, Schedule, Schema } from "effect"
+import { CrossSpawnSpawner } from "@opencode-ai/core/cross-spawn-spawner"
+import { SessionRetry } from "../../src/session/retry"
+import { MessageV2 } from "../../src/session/message-v2"
+import { ProviderError } from "../../src/provider/error"
+import { SessionID } from "../../src/session/schema"
+import { SessionStatus } from "../../src/session/status"
+import { testEffect } from "../lib/effect"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+
+const providerID = ProviderV2.ID.make("test")
+const retryProvider = "test"
+const it = testEffect(Layer.mergeAll(SessionStatus.defaultLayer, CrossSpawnSpawner.defaultLayer))
+
+function apiError(headers?: Record<string, string>): SessionV1.APIError {
+  return Schema.decodeUnknownSync(SessionV1.APIError.Schema)(
+    new SessionV1.APIError({
+      message: "boom",
+      isRetryable: true,
+      responseHeaders: headers,
+    }).toObject(),
+  )
+}
+
+function wrap(message: unknown): ReturnType<NamedError["toObject"]> {
+  return { name: "", data: { message } }
+}
+
+describe("session.retry.delay", () => {
+  test("caps delay at 30 seconds when headers missing", () => {
+    const error = apiError()
+    const delays = Array.from({ length: 10 }, (_, index) => SessionRetry.delay(index + 1, error))
+    expect(delays).toStrictEqual([2000, 4000, 8000, 16000, 30000, 30000, 30000, 30000, 30000, 30000])
+  })
+
+  test("prefers retry-after-ms when shorter than exponential", () => {
+    const error = apiError({ "retry-after-ms": "1500" })
+    expect(SessionRetry.delay(4, error)).toBe(1500)
+  })
+
+  test("uses retry-after seconds when reasonable", () => {
+    const error = apiError({ "retry-after": "30" })
+    expect(SessionRetry.delay(3, error)).toBe(30000)
+  })
+
+  test("accepts http-date retry-after values", () => {
+    const date = new Date(Date.now() + 20000).toUTCString()
+    const error = apiError({ "retry-after": date })
+    const d = SessionRetry.delay(1, error)
+    expect(d).toBeGreaterThanOrEqual(19000)
+    expect(d).toBeLessThanOrEqual(20000)
+  })
+
+  test("ignores invalid retry hints", () => {
+    const error = apiError({ "retry-after": "not-a-number" })
+    expect(SessionRetry.delay(1, error)).toBe(2000)
+  })
+
+  test("ignores malformed date retry hints", () => {
+    const error = apiError({ "retry-after": "Invalid Date String" })
+    expect(SessionRetry.delay(1, error)).toBe(2000)
+  })
+
+  test("ignores past date retry hints", () => {
+    const pastDate = new Date(Date.now() - 5000).toUTCString()
+    const error = apiError({ "retry-after": pastDate })
+    expect(SessionRetry.delay(1, error)).toBe(2000)
+  })
+
+  test("uses retry-after values even when exceeding 10 minutes with headers", () => {
+    const error = apiError({ "retry-after": "50" })
+    expect(SessionRetry.delay(1, error)).toBe(50000)
+
+    const longError = apiError({ "retry-after-ms": "700000" })
+    expect(SessionRetry.delay(1, longError)).toBe(700000)
+  })
+
+  test("caps oversized header delays to the runtime timer limit", () => {
+    const error = apiError({ "retry-after-ms": "999999999999" })
+    expect(SessionRetry.delay(1, error)).toBe(SessionRetry.RETRY_MAX_DELAY)
+  })
+
+  it.instance("policy updates retry status and increments attempts", () =>
+    Effect.gen(function* () {
+      const sessionID = SessionID.make("session-retry-test")
+      const error = apiError({ "retry-after-ms": "0" })
+      const status = yield* SessionStatus.Service
+
+      const step = yield* Schedule.toStepWithMetadata(
+        SessionRetry.policy({
+          provider: "test",
+          parse: Schema.decodeUnknownSync(SessionV1.APIError.Schema),
+          set: (info) =>
+            status.set(sessionID, {
+              type: "retry",
+              attempt: info.attempt,
+              message: info.message,
+              next: info.next,
+            }),
+        }),
+      )
+      yield* step(error)
+      yield* step(error)
+
+      expect(yield* status.get(sessionID)).toMatchObject({
+        type: "retry",
+        attempt: 2,
+        message: "boom",
+      })
+    }),
+  )
+})
+
+describe("session.retry.retryable", () => {
+  test("maps too_many_requests json messages", () => {
+    const error = wrap(JSON.stringify({ type: "error", error: { type: "too_many_requests" } }))
+    expect(SessionRetry.retryable(error, retryProvider)).toEqual({ message: "Too Many Requests" })
+  })
+
+  test("maps overloaded provider codes", () => {
+    const error = wrap(JSON.stringify({ code: "resource_exhausted" }))
+    expect(SessionRetry.retryable(error, retryProvider)).toEqual({ message: "Provider is overloaded" })
+  })
+
+  test("does not retry unknown json messages", () => {
+    const error = wrap(JSON.stringify({ error: { message: "no_kv_space" } }))
+    expect(SessionRetry.retryable(error, retryProvider)).toBeUndefined()
+  })
+
+  test("does not throw on numeric error codes", () => {
+    const error = wrap(JSON.stringify({ type: "error", error: { code: 123 } }))
+    const result = SessionRetry.retryable(error, retryProvider)
+    expect(result).toBeUndefined()
+  })
+
+  test("returns undefined for non-json message", () => {
+    const error = wrap("not-json")
+    expect(SessionRetry.retryable(error, retryProvider)).toBeUndefined()
+  })
+
+  test("retries plain text rate limit errors from Alibaba", () => {
+    const msg =
+      "Upstream error from Alibaba: Request rate increased too quickly. To ensure system stability, please adjust your client logic to scale requests more smoothly over time."
+    const error = wrap(msg)
+    expect(SessionRetry.retryable(error, retryProvider)).toEqual({ message: msg })
+  })
+
+  test("retries plain text rate limit errors", () => {
+    const msg = "Rate limit exceeded, please try again later"
+    const error = wrap(msg)
+    expect(SessionRetry.retryable(error, retryProvider)).toEqual({ message: msg })
+  })
+
+  test("retries too many requests in plain text", () => {
+    const msg = "Too many requests, please slow down"
+    const error = wrap(msg)
+    expect(SessionRetry.retryable(error, retryProvider)).toEqual({ message: msg })
+  })
+
+  test("retries transport timeout errors", () => {
+    const request = MessageV2.fromError(new ProviderError.HeaderTimeoutError(10000), { providerID })
+    expect(SessionV1.APIError.isInstance(request)).toBe(true)
+    expect(SessionRetry.retryable(request, retryProvider)).toEqual({
+      message: "Provider response headers timed out after 10000ms",
+    })
+  })
+
+  test("retries websocket stream transport errors", () => {
+    const request = MessageV2.fromError(
+      new ProviderError.ResponseStreamError("WebSocket closed before response.completed (code 1006: Connection ended)"),
+      { providerID },
+    )
+    expect(SessionV1.APIError.isInstance(request)).toBe(true)
+    expect(SessionRetry.retryable(request, retryProvider)).toEqual({
+      message: "WebSocket closed before response.completed (code 1006: Connection ended)",
+    })
+  })
+
+  test("does not retry context overflow errors", () => {
+    const error = new SessionV1.ContextOverflowError({
+      message: "Input exceeds context window of this model",
+      responseBody: '{"error":{"code":"context_length_exceeded"}}',
+    }).toObject()
+
+    expect(SessionRetry.retryable(error, retryProvider)).toBeUndefined()
+  })
+
+  test("retries 500 errors even when isRetryable is false", () => {
+    const error = Schema.decodeUnknownSync(SessionV1.APIError.Schema)(
+      new SessionV1.APIError({
+        message: "Internal server error",
+        isRetryable: false,
+        statusCode: 500,
+        responseBody: '{"type":"api_error","message":"Internal server error"}',
+      }).toObject(),
+    )
+
+    expect(SessionRetry.retryable(error, retryProvider)).toEqual({ message: "Internal server error" })
+  })
+
+  test("retries 502 bad gateway errors", () => {
+    const error = Schema.decodeUnknownSync(SessionV1.APIError.Schema)(
+      new SessionV1.APIError({
+        message: "Bad gateway",
+        isRetryable: false,
+        statusCode: 502,
+      }).toObject(),
+    )
+
+    expect(SessionRetry.retryable(error, retryProvider)).toEqual({ message: "Bad gateway" })
+  })
+
+  test("retries 503 service unavailable errors", () => {
+    const error = Schema.decodeUnknownSync(SessionV1.APIError.Schema)(
+      new SessionV1.APIError({
+        message: "Service unavailable",
+        isRetryable: false,
+        statusCode: 503,
+      }).toObject(),
+    )
+
+    expect(SessionRetry.retryable(error, retryProvider)).toEqual({ message: "Service unavailable" })
+  })
+
+  test("does not retry 4xx errors when isRetryable is false", () => {
+    const error = Schema.decodeUnknownSync(SessionV1.APIError.Schema)(
+      new SessionV1.APIError({
+        message: "Bad request",
+        isRetryable: false,
+        statusCode: 400,
+      }).toObject(),
+    )
+
+    expect(SessionRetry.retryable(error, retryProvider)).toBeUndefined()
+  })
+
+  test("retries ZlibError decompression failures", () => {
+    const error = Schema.decodeUnknownSync(SessionV1.APIError.Schema)(
+      new SessionV1.APIError({
+        message: "Response decompression failed",
+        isRetryable: true,
+        metadata: { code: "ZlibError" },
+      }).toObject(),
+    )
+
+    const retryable = SessionRetry.retryable(error, retryProvider)
+    expect(retryable).toBeDefined()
+    expect(retryable).toEqual({ message: "Response decompression failed" })
+  })
+
+  test("maps free limits to Go upsell action", () => {
+    const error = Schema.decodeUnknownSync(SessionV1.APIError.Schema)(
+      new SessionV1.APIError({
+        message: "Free usage exceeded",
+        isRetryable: true,
+        statusCode: 429,
+        responseBody: JSON.stringify({
+          type: "error",
+          error: { type: "FreeUsageLimitError", message: "Free usage exceeded" },
+        }),
+      }).toObject(),
+    )
+
+    expect(SessionRetry.retryable(error, "opencode")).toEqual({
+      message: SessionRetry.GO_UPSELL_MESSAGE,
+      action: {
+        reason: "free_tier_limit",
+        provider: "opencode",
+        title: "Free limit reached",
+        message: "Subscribe to OpenCode Go for reliable access to the best open-source models, starting at $5/month.",
+        label: "subscribe",
+        link: SessionRetry.GO_UPSELL_URL,
+      },
+    })
+  })
+
+  test("maps Go subscription limits to workspace PAYG upsell", () => {
+    const error = Schema.decodeUnknownSync(SessionV1.APIError.Schema)(
+      new SessionV1.APIError({
+        message: "Subscription quota exceeded. You can continue using free models.",
+        isRetryable: true,
+        statusCode: 429,
+        responseHeaders: {
+          "retry-after": "19380",
+        },
+        responseBody: JSON.stringify({
+          type: "error",
+          error: {
+            type: "GoUsageLimitError",
+            message: "Subscription quota exceeded. You can continue using free models.",
+          },
+          metadata: {
+            workspace: "wrk_01K6XGM22R6FM8JVABE9XDQXGH",
+            limitName: "5 hour",
+          },
+        }),
+      }).toObject(),
+    )
+
+    expect(SessionRetry.retryable(error, "opencode-go")).toEqual({
+      message:
+        "5 hour usage limit reached. It will reset in 5 hours 23 minutes. To continue using this model now, enable usage from your available balance - https://opencode.ai/workspace/wrk_01K6XGM22R6FM8JVABE9XDQXGH/go",
+      action: {
+        reason: "account_rate_limit",
+        provider: "opencode-go",
+        title: "Go limit reached",
+        message:
+          "5 hour usage limit reached. It will reset in 5 hours 23 minutes. To continue using this model now, enable usage from your available balance",
+        label: "open settings",
+        link: "https://opencode.ai/workspace/wrk_01K6XGM22R6FM8JVABE9XDQXGH/go",
+      },
+    })
+  })
+
+  test("maps Go subscription limits without limit metadata", () => {
+    const error = Schema.decodeUnknownSync(SessionV1.APIError.Schema)(
+      new SessionV1.APIError({
+        message: "Subscription quota exceeded. You can continue using free models.",
+        isRetryable: true,
+        statusCode: 429,
+        responseHeaders: {
+          "retry-after": "900",
+        },
+        responseBody: JSON.stringify({
+          type: "error",
+          error: {
+            type: "GoUsageLimitError",
+            message: "Subscription quota exceeded. You can continue using free models.",
+          },
+          metadata: {
+            workspace: "wrk_01K6XGM22R6FM8JVABE9XDQXGH",
+          },
+        }),
+      }).toObject(),
+    )
+
+    expect(SessionRetry.retryable(error, "opencode-go")?.action?.message).toBe(
+      "Usage limit reached. It will reset in 15 minutes. To continue using this model now, enable usage from your available balance",
+    )
+  })
+})
+
+describe("session.message-v2.fromError", () => {
+  test.concurrent(
+    "converts ECONNRESET socket errors to retryable APIError",
+    async () => {
+      using server = Bun.serve({
+        port: 0,
+        idleTimeout: 8,
+        async fetch(_req) {
+          return new Response(
+            new ReadableStream({
+              async pull(controller) {
+                controller.enqueue("Hello,")
+                await sleep(10000)
+                controller.enqueue(" World!")
+                controller.close()
+              },
+            }),
+            { headers: { "Content-Type": "text/plain" } },
+          )
+        },
+      })
+
+      const error = await fetch(new URL("/", server.url.origin))
+        .then((res) => res.text())
+        .catch((e) => e)
+
+      const result = MessageV2.fromError(error, { providerID })
+
+      expect(SessionV1.APIError.isInstance(result)).toBe(true)
+      if (!SessionV1.APIError.isInstance(result)) throw new Error("expected APIError")
+      expect(result.data.isRetryable).toBe(true)
+      expect(result.data.message).toBe("Connection reset by server")
+      expect(result.data.metadata?.code).toBe("ECONNRESET")
+      expect(result.data.metadata?.message).toInclude("socket connection")
+    },
+    15_000,
+  )
+
+  test("ECONNRESET socket error is retryable", () => {
+    const error = Schema.decodeUnknownSync(SessionV1.APIError.Schema)(
+      new SessionV1.APIError({
+        message: "Connection reset by server",
+        isRetryable: true,
+        metadata: { code: "ECONNRESET", message: "The socket connection was closed unexpectedly" },
+      }).toObject(),
+    )
+
+    const retryable = SessionRetry.retryable(error, retryProvider)
+    expect(retryable).toBeDefined()
+    expect(retryable).toEqual({ message: "Connection reset by server" })
+  })
+
+  test("marks OpenAI 404 status codes as retryable", () => {
+    const error = new APICallError({
+      message: "boom",
+      url: "https://api.openai.com/v1/chat/completions",
+      requestBodyValues: {},
+      statusCode: 404,
+      responseHeaders: { "content-type": "application/json" },
+      responseBody: '{"error":"boom"}',
+      isRetryable: false,
+    })
+    const result = MessageV2.fromError(error, { providerID: ProviderV2.ID.make("openai") })
+    if (!SessionV1.APIError.isInstance(result)) throw new Error("expected APIError")
+    expect(result.data.isRetryable).toBe(true)
+  })
+
+  test("converts OpenAI server_error stream chunks to retryable APIError", () => {
+    const result = MessageV2.fromError(
+      {
+        message: JSON.stringify({
+          type: "error",
+          sequence_number: 2,
+          error: {
+            type: "server_error",
+            code: "server_error",
+            message: "An error occurred while processing your request.",
+            param: null,
+          },
+        }),
+      },
+      { providerID: ProviderV2.ID.make("openai") },
+    )
+
+    expect(SessionV1.APIError.isInstance(result)).toBe(true)
+    if (!SessionV1.APIError.isInstance(result)) throw new Error("expected APIError")
+    expect(result.data.isRetryable).toBe(true)
+    expect(SessionRetry.retryable(result, retryProvider)).toEqual({
+      message: "An error occurred while processing your request.",
+    })
+  })
+})

packages/opencode/test/session/revert-compact.test.ts

@@ -0,0 +1,639 @@
+import { describe, expect } from "bun:test"
+import { SessionV1 } from "@opencode-ai/core/v1/session"
+import fs from "fs/promises"
+import path from "path"
+import { Effect, Layer } from "effect"
+import { Session } from "@/session/session"
+
+import { SessionRevert } from "../../src/session/revert"
+import { MessageV2 } from "../../src/session/message-v2"
+import { Snapshot } from "../../src/snapshot"
+import { MessageID, PartID, SessionID } from "../../src/session/schema"
+import { CrossSpawnSpawner } from "@opencode-ai/core/cross-spawn-spawner"
+import { provideTmpdirInstance } from "../fixture/fixture"
+import { testEffect } from "../lib/effect"
+import { ProviderV2 } from "@opencode-ai/core/provider"
+import { ModelV2 } from "@opencode-ai/core/model"
+
+const env = Layer.mergeAll(
+  Session.defaultLayer,
+  SessionRevert.defaultLayer,
+  Snapshot.defaultLayer,
+  CrossSpawnSpawner.defaultLayer,
+)
+
+const it = testEffect(env)
+
+const user = Effect.fn("test.user")(function* (sessionID: SessionID, agent = "default") {
+  const session = yield* Session.Service
+  return yield* session.updateMessage({
+    id: MessageID.ascending(),
+    role: "user" as const,
+    sessionID,
+    agent,
+    model: { providerID: ProviderV2.ID.make("openai"), modelID: ModelV2.ID.make("gpt-4") },
+    time: { created: Date.now() },
+  })
+})
+
+const assistant = Effect.fn("test.assistant")(function* (sessionID: SessionID, parentID: MessageID, dir: string) {
+  const session = yield* Session.Service
+  return yield* session.updateMessage({
+    id: MessageID.ascending(),
+    role: "assistant" as const,
+    sessionID,
+    mode: "default",
+    agent: "default",
+    path: { cwd: dir, root: dir },
+    cost: 0,
+    tokens: { output: 0, input: 0, reasoning: 0, cache: { read: 0, write: 0 } },
+    modelID: ModelV2.ID.make("gpt-4"),
+    providerID: ProviderV2.ID.make("openai"),
+    parentID,
+    time: { created: Date.now() },
+    finish: "end_turn",
+  })
+})
+
+const text = Effect.fn("test.text")(function* (sessionID: SessionID, messageID: MessageID, content: string) {
+  const session = yield* Session.Service
+  return yield* session.updatePart({
+    id: PartID.ascending(),
+    messageID,
+    sessionID,
+    type: "text" as const,
+    text: content,
+  })
+})
+
+const tool = Effect.fn("test.tool")(function* (sessionID: SessionID, messageID: MessageID) {
+  const session = yield* Session.Service
+  return yield* session.updatePart({
+    id: PartID.ascending(),
+    messageID,
+    sessionID,
+    type: "tool" as const,
+    tool: "bash",
+    callID: "call-1",
+    state: {
+      status: "completed" as const,
+      input: {},
+      output: "done",
+      title: "",
+      metadata: {},
+      time: { start: 0, end: 1 },
+    },
+  })
+})
+
+const read = (file: string) => Effect.promise(() => fs.readFile(file, "utf-8"))
+const write = (file: string, text: string) => Effect.promise(() => fs.writeFile(file, text))
+
+const tokens = {
+  input: 0,
+  output: 0,
+  reasoning: 0,
+  cache: { read: 0, write: 0 },
+}
+
+describe("revert + compact workflow", () => {
+  it.live(
+    "should properly handle compact command after revert",
+    provideTmpdirInstance(
+      (dir) =>
+        Effect.gen(function* () {
+          const session = yield* Session.Service
+          const revert = yield* SessionRevert.Service
+
+          const info = yield* session.create({})
+          const sessionID = info.id
+
+          const userMsg1 = yield* session.updateMessage({
+            id: MessageID.ascending(),
+            role: "user",
+            sessionID,
+            agent: "default",
+            model: {
+              providerID: ProviderV2.ID.make("openai"),
+              modelID: ModelV2.ID.make("gpt-4"),
+            },
+            time: {
+              created: Date.now(),
+            },
+          })
+
+          yield* session.updatePart({
+            id: PartID.ascending(),
+            messageID: userMsg1.id,
+            sessionID,
+            type: "text",
+            text: "Hello, please help me",
+          })
+
+          const assistantMsg1: SessionV1.Assistant = {
+            id: MessageID.ascending(),
+            role: "assistant",
+            sessionID,
+            mode: "default",
+            agent: "default",
+            path: {
+              cwd: dir,
+              root: dir,
+            },
+            cost: 0,
+            tokens: {
+              output: 0,
+              input: 0,
+              reasoning: 0,
+              cache: { read: 0, write: 0 },
+            },
+            modelID: ModelV2.ID.make("gpt-4"),
+            providerID: ProviderV2.ID.make("openai"),
+            parentID: userMsg1.id,
+            time: {
+              created: Date.now(),
+            },
+            finish: "end_turn",
+          }
+          yield* session.updateMessage(assistantMsg1)
+
+          yield* session.updatePart({
+            id: PartID.ascending(),
+            messageID: assistantMsg1.id,
+            sessionID,
+            type: "text",
+            text: "Sure, I'll help you!",
+          })
+
+          const userMsg2 = yield* session.updateMessage({
+            id: MessageID.ascending(),
+            role: "user",
+            sessionID,
+            agent: "default",
+            model: {
+              providerID: ProviderV2.ID.make("openai"),
+              modelID: ModelV2.ID.make("gpt-4"),
+            },
+            time: {
+              created: Date.now(),
+            },
+          })
+
+          yield* session.updatePart({
+            id: PartID.ascending(),
+            messageID: userMsg2.id,
+            sessionID,
+            type: "text",
+            text: "What's the capital of France?",
+          })
+
+          const assistantMsg2: SessionV1.Assistant = {
+            id: MessageID.ascending(),
+            role: "assistant",
+            sessionID,
+            mode: "default",
+            agent: "default",
+            path: {
+              cwd: dir,
+              root: dir,
+            },
+            cost: 0,
+            tokens: {
+              output: 0,
+              input: 0,
+              reasoning: 0,
+              cache: { read: 0, write: 0 },
+            },
+            modelID: ModelV2.ID.make("gpt-4"),
+            providerID: ProviderV2.ID.make("openai"),
+            parentID: userMsg2.id,
+            time: {
+              created: Date.now(),
+            },
+            finish: "end_turn",
+          }
+          yield* session.updateMessage(assistantMsg2)
+
+          yield* session.updatePart({
+            id: PartID.ascending(),
+            messageID: assistantMsg2.id,
+            sessionID,
+            type: "text",
+            text: "The capital of France is Paris.",
+          })
+
+          let messages = yield* session.messages({ sessionID })
+          expect(messages.length).toBe(4)
+          const messageIds = messages.map((m) => m.info.id)
+          expect(messageIds).toContain(userMsg1.id)
+          expect(messageIds).toContain(userMsg2.id)
+          expect(messageIds).toContain(assistantMsg1.id)
+          expect(messageIds).toContain(assistantMsg2.id)
+
+          yield* revert.revert({
+            sessionID,
+            messageID: userMsg2.id,
+          })
+
+          let sessionInfo = yield* session.get(sessionID)
+          expect(sessionInfo.revert).toBeDefined()
+          expect(sessionInfo.revert?.messageID).toBeDefined()
+
+          messages = yield* session.messages({ sessionID })
+          expect(messages.length).toBe(4)
+
+          yield* revert.cleanup(sessionInfo)
+
+          messages = yield* session.messages({ sessionID })
+          const remainingIds = messages.map((m) => m.info.id)
+          expect(messages.length).toBeLessThan(4)
+          expect(remainingIds).not.toContain(userMsg2.id)
+          expect(remainingIds).not.toContain(assistantMsg2.id)
+
+          sessionInfo = yield* session.get(sessionID)
+          expect(sessionInfo.revert).toBeUndefined()
+
+          yield* session.remove(sessionID)
+        }),
+      { git: true },
+    ),
+  )
+
+  it.live(
+    "should properly clean up revert state before creating compaction message",
+    provideTmpdirInstance(
+      (dir) =>
+        Effect.gen(function* () {
+          const session = yield* Session.Service
+          const revert = yield* SessionRevert.Service
+
+          const info = yield* session.create({})
+          const sessionID = info.id
+
+          const userMsg = yield* session.updateMessage({
+            id: MessageID.ascending(),
+            role: "user",
+            sessionID,
+            agent: "default",
+            model: {
+              providerID: ProviderV2.ID.make("openai"),
+              modelID: ModelV2.ID.make("gpt-4"),
+            },
+            time: {
+              created: Date.now(),
+            },
+          })
+
+          yield* session.updatePart({
+            id: PartID.ascending(),
+            messageID: userMsg.id,
+            sessionID,
+            type: "text",
+            text: "Hello",
+          })
+
+          const assistantMsg: SessionV1.Assistant = {
+            id: MessageID.ascending(),
+            role: "assistant",
+            sessionID,
+            mode: "default",
+            agent: "default",
+            path: {
+              cwd: dir,
+              root: dir,
+            },
+            cost: 0,
+            tokens: {
+              output: 0,
+              input: 0,
+              reasoning: 0,
+              cache: { read: 0, write: 0 },
+            },
+            modelID: ModelV2.ID.make("gpt-4"),
+            providerID: ProviderV2.ID.make("openai"),
+            parentID: userMsg.id,
+            time: {
+              created: Date.now(),
+            },
+            finish: "end_turn",
+          }
+          yield* session.updateMessage(assistantMsg)
+
+          yield* session.updatePart({
+            id: PartID.ascending(),
+            messageID: assistantMsg.id,
+            sessionID,
+            type: "text",
+            text: "Hi there!",
+          })
+
+          yield* revert.revert({
+            sessionID,
+            messageID: userMsg.id,
+          })
+
+          let sessionInfo = yield* session.get(sessionID)
+          expect(sessionInfo.revert).toBeDefined()
+
+          yield* revert.cleanup(sessionInfo)
+
+          sessionInfo = yield* session.get(sessionID)
+          expect(sessionInfo.revert).toBeUndefined()
+
+          const messages = yield* session.messages({ sessionID })
+          expect(messages.length).toBe(0)
+
+          yield* session.remove(sessionID)
+        }),
+      { git: true },
+    ),
+  )
+
+  it.live(
+    "cleanup with partID removes parts from the revert point onward",
+    provideTmpdirInstance(
+      () =>
+        Effect.gen(function* () {
+          const session = yield* Session.Service
+          const revert = yield* SessionRevert.Service
+
+          const info = yield* session.create({})
+          const sid = info.id
+
+          const u1 = yield* user(sid)
+          const p1 = yield* text(sid, u1.id, "first part")
+          const p2 = yield* tool(sid, u1.id)
+          yield* text(sid, u1.id, "third part")
+
+          yield* session.setRevert({
+            sessionID: sid,
+            revert: { messageID: u1.id, partID: p2.id },
+            summary: { additions: 0, deletions: 0, files: 0 },
+          })
+
+          const state = yield* session.get(sid)
+          yield* revert.cleanup(state)
+
+          const msgs = yield* session.messages({ sessionID: sid })
+          expect(msgs.length).toBe(1)
+          expect(msgs[0].parts.length).toBe(1)
+          expect(msgs[0].parts[0].id).toBe(p1.id)
+
+          const cleared = yield* session.get(sid)
+          expect(cleared.revert).toBeUndefined()
+        }),
+      { git: true },
+    ),
+  )
+
+  it.live(
+    "cleanup removes messages after revert point but keeps earlier ones",
+    provideTmpdirInstance(
+      (dir) =>
+        Effect.gen(function* () {
+          const session = yield* Session.Service
+          const revert = yield* SessionRevert.Service
+
+          const info = yield* session.create({})
+          const sid = info.id
+
+          const u1 = yield* user(sid)
+          yield* text(sid, u1.id, "hello")
+          const a1 = yield* assistant(sid, u1.id, dir)
+          yield* text(sid, a1.id, "hi back")
+
+          const u2 = yield* user(sid)
+          yield* text(sid, u2.id, "second question")
+          const a2 = yield* assistant(sid, u2.id, dir)
+          yield* text(sid, a2.id, "second answer")
+
+          yield* session.setRevert({
+            sessionID: sid,
+            revert: { messageID: u2.id },
+            summary: { additions: 0, deletions: 0, files: 0 },
+          })
+
+          const state = yield* session.get(sid)
+          yield* revert.cleanup(state)
+
+          const msgs = yield* session.messages({ sessionID: sid })
+          const ids = msgs.map((m) => m.info.id)
+          expect(ids).toContain(u1.id)
+          expect(ids).toContain(a1.id)
+          expect(ids).not.toContain(u2.id)
+          expect(ids).not.toContain(a2.id)
+        }),
+      { git: true },
+    ),
+  )
+
+  it.live(
+    "cleanup is a no-op when session has no revert state",
+    provideTmpdirInstance(
+      () =>
+        Effect.gen(function* () {
+          const session = yield* Session.Service
+          const revert = yield* SessionRevert.Service
+
+          const info = yield* session.create({})
+          const sid = info.id
+
+          const u1 = yield* user(sid)
+          yield* text(sid, u1.id, "hello")
+
+          const state = yield* session.get(sid)
+          expect(state.revert).toBeUndefined()
+          yield* revert.cleanup(state)
+
+          const msgs = yield* session.messages({ sessionID: sid })
+          expect(msgs.length).toBe(1)
+        }),
+      { git: true },
+    ),
+  )
+
+  it.live(
+    "restore messages in sequential order",
+    provideTmpdirInstance(
+      (dir) =>
+        Effect.gen(function* () {
+          const session = yield* Session.Service
+          const revert = yield* SessionRevert.Service
+          const snapshot = yield* Snapshot.Service
+
+          yield* write(path.join(dir, "a.txt"), "a0")
+          yield* write(path.join(dir, "b.txt"), "b0")
+          yield* write(path.join(dir, "c.txt"), "c0")
+
+          const info = yield* session.create({})
+          const sid = info.id
+
+          const turn = Effect.fn("test.turn")(function* (file: string, next: string) {
+            const u = yield* user(sid)
+            yield* text(sid, u.id, `${file}:${next}`)
+            const a = yield* assistant(sid, u.id, dir)
+            const before = yield* snapshot.track()
+            if (!before) throw new Error("expected snapshot")
+            yield* write(path.join(dir, file), next)
+            const after = yield* snapshot.track()
+            if (!after) throw new Error("expected snapshot")
+            const patch = yield* snapshot.patch(before)
+            yield* session.updatePart({
+              id: PartID.ascending(),
+              messageID: a.id,
+              sessionID: sid,
+              type: "step-start",
+              snapshot: before,
+            })
+            yield* session.updatePart({
+              id: PartID.ascending(),
+              messageID: a.id,
+              sessionID: sid,
+              type: "step-finish",
+              reason: "stop",
+              snapshot: after,
+              cost: 0,
+              tokens,
+            })
+            yield* session.updatePart({
+              id: PartID.ascending(),
+              messageID: a.id,
+              sessionID: sid,
+              type: "patch",
+              hash: patch.hash,
+              files: patch.files,
+            })
+            return u.id
+          })
+
+          const first = yield* turn("a.txt", "a1")
+          const second = yield* turn("b.txt", "b2")
+          const third = yield* turn("c.txt", "c3")
+
+          yield* revert.revert({
+            sessionID: sid,
+            messageID: first,
+          })
+          expect((yield* session.get(sid)).revert?.messageID).toBe(first)
+          expect(yield* read(path.join(dir, "a.txt"))).toBe("a0")
+          expect(yield* read(path.join(dir, "b.txt"))).toBe("b0")
+          expect(yield* read(path.join(dir, "c.txt"))).toBe("c0")
+
+          yield* revert.revert({
+            sessionID: sid,
+            messageID: second,
+          })
+          expect((yield* session.get(sid)).revert?.messageID).toBe(second)
+          expect(yield* read(path.join(dir, "a.txt"))).toBe("a1")
+          expect(yield* read(path.join(dir, "b.txt"))).toBe("b0")
+          expect(yield* read(path.join(dir, "c.txt"))).toBe("c0")
+
+          yield* revert.revert({
+            sessionID: sid,
+            messageID: third,
+          })
+          expect((yield* session.get(sid)).revert?.messageID).toBe(third)
+          expect(yield* read(path.join(dir, "a.txt"))).toBe("a1")
+          expect(yield* read(path.join(dir, "b.txt"))).toBe("b2")
+          expect(yield* read(path.join(dir, "c.txt"))).toBe("c0")
+
+          yield* revert.unrevert({
+            sessionID: sid,
+          })
+          expect((yield* session.get(sid)).revert).toBeUndefined()
+          expect(yield* read(path.join(dir, "a.txt"))).toBe("a1")
+          expect(yield* read(path.join(dir, "b.txt"))).toBe("b2")
+          expect(yield* read(path.join(dir, "c.txt"))).toBe("c3")
+        }),
+      { git: true },
+    ),
+  )
+
+  it.live(
+    "restore same file in sequential order",
+    provideTmpdirInstance(
+      (dir) =>
+        Effect.gen(function* () {
+          const session = yield* Session.Service
+          const revert = yield* SessionRevert.Service
+          const snapshot = yield* Snapshot.Service
+
+          yield* write(path.join(dir, "a.txt"), "a0")
+
+          const info = yield* session.create({})
+          const sid = info.id
+
+          const turn = Effect.fn("test.turnSame")(function* (next: string) {
+            const u = yield* user(sid)
+            yield* text(sid, u.id, `a.txt:${next}`)
+            const a = yield* assistant(sid, u.id, dir)
+            const before = yield* snapshot.track()
+            if (!before) throw new Error("expected snapshot")
+            yield* write(path.join(dir, "a.txt"), next)
+            const after = yield* snapshot.track()
+            if (!after) throw new Error("expected snapshot")
+            const patch = yield* snapshot.patch(before)
+            yield* session.updatePart({
+              id: PartID.ascending(),
+              messageID: a.id,
+              sessionID: sid,
+              type: "step-start",
+              snapshot: before,
+            })
+            yield* session.updatePart({
+              id: PartID.ascending(),
+              messageID: a.id,
+              sessionID: sid,
+              type: "step-finish",
+              reason: "stop",
+              snapshot: after,
+              cost: 0,
+              tokens,
+            })
+            yield* session.updatePart({
+              id: PartID.ascending(),
+              messageID: a.id,
+              sessionID: sid,
+              type: "patch",
+              hash: patch.hash,
+              files: patch.files,
+            })
+            return u.id
+          })
+
+          const first = yield* turn("a1")
+          const second = yield* turn("a2")
+          const third = yield* turn("a3")
+          expect(yield* read(path.join(dir, "a.txt"))).toBe("a3")
+
+          yield* revert.revert({
+            sessionID: sid,
+            messageID: first,
+          })
+          expect((yield* session.get(sid)).revert?.messageID).toBe(first)
+          expect(yield* read(path.join(dir, "a.txt"))).toBe("a0")
+
+          yield* revert.revert({
+            sessionID: sid,
+            messageID: second,
+          })
+          expect((yield* session.get(sid)).revert?.messageID).toBe(second)
+          expect(yield* read(path.join(dir, "a.txt"))).toBe("a1")
+
+          yield* revert.revert({
+            sessionID: sid,
+            messageID: third,
+          })
+          expect((yield* session.get(sid)).revert?.messageID).toBe(third)
+          expect(yield* read(path.join(dir, "a.txt"))).toBe("a2")
+
+          yield* revert.unrevert({
+            sessionID: sid,
+          })
+          expect((yield* session.get(sid)).revert).toBeUndefined()
+          expect(yield* read(path.join(dir, "a.txt"))).toBe("a3")
+        }),
+      { git: true },
+    ),
+  )
+})

packages/opencode/test/session/schema-decoding.test.ts

@@ -0,0 +1,313 @@
+import { describe, expect, test } from "bun:test"
+import { Schema } from "effect"
+
+import { Session } from "@/session/session"
+import { SessionPrompt } from "../../src/session/prompt"
+import { SessionRevert } from "../../src/session/revert"
+import { SessionStatus } from "../../src/session/status"
+import { SessionSummary } from "../../src/session/summary"
+import { Todo } from "../../src/session/todo"
+import { SessionID, MessageID, PartID } from "../../src/session/schema"
+import { ProjectV2 } from "@opencode-ai/core/project"
+import { WorkspaceV2 } from "@opencode-ai/core/workspace"
+
+// Covers the session-domain Effect Schema migration. For each migrated
+// schema we assert:
+//   1. The Effect decoder (`Schema.decodeUnknownSync`) accepts valid input.
+//   2. Clearly-invalid input is rejected.
+
+// Representative valid IDs — the branded schemas require the right prefix
+// (see src/id/id.ts).
+const sessionID = Schema.decodeUnknownSync(SessionID)("ses_01J5Y5H0AH4Q4NXJ6P4C3P5V2K")
+const sessionIDChild = Schema.decodeUnknownSync(SessionID)("ses_01J5Y5H0AH4Q4NXJ6P4C3P5V2L")
+const messageID = Schema.decodeUnknownSync(MessageID)("msg_01J5Y5H0AH4Q4NXJ6P4C3P5V2M")
+const partID = Schema.decodeUnknownSync(PartID)("prt_01J5Y5H0AH4Q4NXJ6P4C3P5V2N")
+const projectID = ProjectV2.ID.make("proj-alpha")
+const workspaceID = Schema.decodeUnknownSync(WorkspaceV2.ID)("wrk-primary")
+
+function decodeUnknown<S extends Schema.Top>(schema: S) {
+  const decode = Schema.decodeUnknownSync(schema as any)
+  return (input: unknown): Schema.Schema.Type<S> => decode(input) as Schema.Schema.Type<S>
+}
+
+describe("Session.Info", () => {
+  const decode = decodeUnknown(Session.Info)
+
+  test("accepts minimal session", () => {
+    const input = {
+      id: sessionID,
+      slug: "hello",
+      projectID,
+      directory: "/tmp/proj",
+      title: "First session",
+      version: "0.1.0",
+      time: { created: 1, updated: 2 },
+    }
+    expect(decode(input)).toEqual(input)
+  })
+
+  test("round-trips every optional field", () => {
+    const input = {
+      id: sessionID,
+      slug: "fullshape",
+      projectID,
+      workspaceID,
+      directory: "/tmp/proj",
+      path: "packages/opencode",
+      parentID: sessionIDChild,
+      summary: {
+        additions: 10,
+        deletions: 5,
+        files: 2,
+        diffs: [{ additions: 1, deletions: 0, file: "a.ts", patch: "--- a/a.ts" }],
+      },
+      share: { url: "https://share.example.com/s/1" },
+      title: "Full session",
+      version: "1.0.0",
+      metadata: { source: "test" },
+      time: { created: 100, updated: 200, compacting: 150, archived: 300 },
+      permission: [{ action: "allow" as const, pattern: "*", permission: "read" }],
+      revert: {
+        messageID,
+        partID,
+        snapshot: "snap-1",
+        diff: "diff-1",
+      },
+    }
+    expect(decode(input)).toEqual(input)
+  })
+
+  test("accepts migrated summary diffs without file details", () => {
+    const input = {
+      id: sessionID,
+      slug: "legacy-diff",
+      projectID,
+      directory: "/tmp/proj",
+      title: "Legacy diff",
+      version: "0.1.0",
+      summary: {
+        additions: 1,
+        deletions: 0,
+        files: 1,
+        diffs: [{ additions: 1, deletions: 0 }],
+      },
+      time: { created: 1, updated: 2 },
+    }
+    expect(decode(input)).toEqual(input)
+  })
+
+  test("rejects unbranded session id", () => {
+    const bad = { id: "not-a-session-id" } as unknown
+    expect(() => decode(bad)).toThrow()
+  })
+
+  test("rejects missing required fields", () => {
+    const bad = { id: sessionID } as unknown
+    expect(() => decode(bad)).toThrow()
+  })
+})
+
+describe("Session.ProjectInfo", () => {
+  const decode = decodeUnknown(Session.ProjectInfo)
+
+  test("accepts with and without optional name", () => {
+    const noName = { id: projectID, worktree: "/tmp/wt" }
+    const withName = { ...noName, name: "alpha" }
+    expect(decode(noName)).toEqual(noName)
+    expect(decode(withName)).toEqual(withName)
+  })
+})
+
+describe("Session.GlobalInfo", () => {
+  const decode = decodeUnknown(Session.GlobalInfo)
+
+  test("accepts null project", () => {
+    const input = {
+      id: sessionID,
+      slug: "global",
+      projectID,
+      directory: "/tmp/proj",
+      title: "global",
+      version: "0",
+      time: { created: 0, updated: 0 },
+      project: null,
+    }
+    expect(decode(input)).toEqual(input)
+  })
+
+  test("accepts populated project", () => {
+    const input = {
+      id: sessionID,
+      slug: "global",
+      projectID,
+      directory: "/tmp/proj",
+      title: "global",
+      version: "0",
+      time: { created: 0, updated: 0 },
+      project: { id: projectID, worktree: "/tmp/wt", name: "alpha" },
+    }
+    expect(decode(input)).toEqual(input)
+  })
+})
+
+describe("Session input schemas", () => {
+  test("CreateInput accepts undefined and populated forms", () => {
+    const decode = decodeUnknown(Session.CreateInput)
+    expect(decode(undefined)).toBeUndefined()
+
+    const populated = {
+      parentID: sessionID,
+      title: "child",
+      metadata: { source: "test" },
+      permission: [{ action: "ask" as const, pattern: "*", permission: "bash" }],
+      workspaceID,
+    }
+    expect(decode(populated)).toEqual(populated)
+  })
+
+  test("ForkInput round-trips", () => {
+    const decode = decodeUnknown(Session.ForkInput)
+    const input = { sessionID, messageID }
+    expect(decode(input)).toEqual(input)
+    // messageID is optional
+    const bare = { sessionID }
+    expect(decode(bare)).toEqual(bare)
+  })
+
+  test("SetTitleInput rejects missing title", () => {
+    expect(() => decodeUnknown(Session.SetTitleInput)({ sessionID })).toThrow()
+  })
+
+  test("SetArchivedInput accepts both with and without time", () => {
+    const decode = decodeUnknown(Session.SetArchivedInput)
+    expect(decode({ sessionID })).toEqual({ sessionID })
+    expect(decode({ sessionID, time: 123 })).toEqual({ sessionID, time: 123 })
+  })
+
+  test("SetPermissionInput requires a ruleset", () => {
+    const decode = decodeUnknown(Session.SetPermissionInput)
+    const input = { sessionID, permission: [{ action: "deny" as const, pattern: "*", permission: "write" }] }
+    expect(decode(input)).toEqual(input)
+    expect(() => decode({ sessionID })).toThrow()
+  })
+
+  test("MessagesInput accepts optional limit", () => {
+    const decode = decodeUnknown(Session.MessagesInput)
+    expect(decode({ sessionID })).toEqual({ sessionID })
+    expect(decode({ sessionID, limit: 50 })).toEqual({ sessionID, limit: 50 })
+  })
+})
+
+describe("SessionRevert.RevertInput", () => {
+  const decode = decodeUnknown(SessionRevert.RevertInput)
+
+  test("messageID is required, partID is optional", () => {
+    const withPart = { sessionID, messageID, partID }
+    expect(decode(withPart)).toEqual(withPart)
+
+    const noPart = { sessionID, messageID }
+    expect(decode(noPart)).toEqual(noPart)
+
+    expect(() => decode({ sessionID })).toThrow()
+  })
+})
+
+describe("SessionSummary.DiffInput", () => {
+  const decode = decodeUnknown(SessionSummary.DiffInput)
+
+  test("messageID optional", () => {
+    expect(decode({ sessionID })).toEqual({ sessionID })
+    expect(decode({ sessionID, messageID })).toEqual({ sessionID, messageID })
+  })
+})
+
+describe("SessionStatus.Info", () => {
+  const decode = decodeUnknown(SessionStatus.Info)
+
+  test("idle / busy discriminators", () => {
+    expect(decode({ type: "idle" })).toEqual({ type: "idle" })
+    expect(decode({ type: "busy" })).toEqual({ type: "busy" })
+  })
+
+  test("retry carries attempt/message/action/next", () => {
+    const input = {
+      type: "retry" as const,
+      attempt: 1,
+      message: "transient",
+      action: {
+        reason: "free_tier_limit",
+        provider: "opencode",
+        title: "Free limit reached",
+        message: "Subscribe to OpenCode Go.",
+        label: "subscribe",
+        link: "https://opencode.ai/go",
+      },
+      next: 500,
+    }
+    expect(decode(input)).toEqual(input)
+  })
+
+  test("rejects unknown type", () => {
+    expect(() => decode({ type: "bogus" })).toThrow()
+  })
+})
+
+describe("Todo.Info", () => {
+  const decode = decodeUnknown(Todo.Info)
+
+  test("three-field round-trip", () => {
+    const input = { content: "do a thing", status: "pending", priority: "high" }
+    expect(decode(input)).toEqual(input)
+  })
+})
+
+describe("SessionPrompt input schemas", () => {
+  test("LoopInput is just sessionID", () => {
+    const decode = decodeUnknown(SessionPrompt.LoopInput)
+    expect(decode({ sessionID })).toEqual({ sessionID })
+  })
+
+  test("ShellInput requires agent + command", () => {
+    const decode = decodeUnknown(SessionPrompt.ShellInput)
+    const expected = { sessionID, agent: "build", command: "echo hi" }
+    const input: unknown = expected
+    expect(decode(input)).toEqual(expected)
+    expect(() => decode({ sessionID })).toThrow()
+  })
+
+  test("PromptInput accepts a text part and a file part", () => {
+    const decode = decodeUnknown(SessionPrompt.PromptInput)
+    const expected = {
+      sessionID,
+      parts: [
+        { type: "text" as const, text: "hello" },
+        { type: "file" as const, mime: "image/png", url: "data:image/png;base64,AAAA" },
+      ],
+    }
+    const input: unknown = expected
+    const decoded = decode(input)
+    expect(decoded.parts).toHaveLength(2)
+    expect(decoded.parts[0]).toMatchObject({ type: "text", text: "hello" })
+    expect(decoded.parts[1]).toMatchObject({ type: "file", mime: "image/png" })
+  })
+
+  test("PromptInput rejects unknown part type", () => {
+    const decode = decodeUnknown(SessionPrompt.PromptInput)
+    const bad = {
+      sessionID,
+      parts: [{ type: "nonsense", payload: 42 }],
+    }
+    expect(() => decode(bad)).toThrow()
+  })
+
+  test("CommandInput round-trips core fields", () => {
+    const decode = decodeUnknown(SessionPrompt.CommandInput)
+    const expected = {
+      sessionID,
+      arguments: "--flag",
+      command: "deploy",
+    }
+    const input: unknown = expected
+    expect(decode(input)).toEqual(expected)
+  })
+})

packages/opencode/test/session/session-schema.test.ts

@@ -0,0 +1,78 @@
+import { describe, expect, test } from "bun:test"
+import { Schema } from "effect"
+import { ProjectV2 } from "@opencode-ai/core/project"
+import { MessageID, SessionID } from "../../src/session/schema"
+import { Session } from "../../src/session/session"
+
+const info = {
+  id: SessionID.descending(),
+  slug: "test-session",
+  projectID: ProjectV2.ID.global,
+  workspaceID: undefined,
+  directory: "/tmp/opencode",
+  parentID: undefined,
+  summary: undefined,
+  cost: 0,
+  tokens: { input: 0, output: 0, reasoning: 0, cache: { read: 0, write: 0 } },
+  share: undefined,
+  title: "Test session",
+  version: "1.0.0",
+  time: {
+    created: 1,
+    updated: 2,
+    compacting: undefined,
+    archived: undefined,
+  },
+  permission: undefined,
+  revert: undefined,
+} satisfies Session.Info
+
+describe("Session schema", () => {
+  test("encodes undefined optional session fields as omitted keys", () => {
+    const encoded = Schema.encodeUnknownSync(Session.Info)(info) as Record<string, unknown>
+
+    for (const key of ["workspaceID", "parentID", "summary", "share", "permission", "revert"]) {
+      expect(Object.hasOwn(encoded, key)).toBe(false)
+    }
+    expect(Object.hasOwn(encoded.time as Record<string, unknown>, "compacting")).toBe(false)
+    expect(Object.hasOwn(encoded.time as Record<string, unknown>, "archived")).toBe(false)
+    expect(JSON.stringify(encoded)).not.toContain("parentID")
+  })
+
+  test("encodes undefined optional global session project fields as omitted keys", () => {
+    const encoded = Schema.encodeUnknownSync(Session.GlobalInfo)({
+      ...info,
+      project: {
+        id: ProjectV2.ID.global,
+        name: undefined,
+        worktree: "/tmp/opencode",
+      },
+    }) as Record<string, unknown>
+
+    expect(Object.hasOwn(encoded, "parentID")).toBe(false)
+    expect(Object.hasOwn(encoded.project as Record<string, unknown>, "name")).toBe(false)
+  })
+
+  test("encodes nested undefined optional session fields as omitted keys", () => {
+    const encoded = Schema.encodeUnknownSync(Session.Info)({
+      ...info,
+      summary: {
+        additions: 1,
+        deletions: 2,
+        files: 3,
+        diffs: undefined,
+      },
+      revert: {
+        messageID: MessageID.ascending(),
+        partID: undefined,
+        snapshot: undefined,
+        diff: undefined,
+      },
+    }) as Record<string, unknown>
+
+    expect(Object.hasOwn(encoded.summary as Record<string, unknown>, "diffs")).toBe(false)
+    for (const key of ["partID", "snapshot", "diff"]) {
+      expect(Object.hasOwn(encoded.revert as Record<string, unknown>, key)).toBe(false)
+    }
+  })
+})

packages/opencode/test/session/session.test.ts

@@ -0,0 +1,248 @@
+import { describe, expect } from "bun:test"
+import { SessionV1 } from "@opencode-ai/core/v1/session"
+import { Database } from "@opencode-ai/core/database/database"
+import { EventV2 } from "@opencode-ai/core/event"
+import { SessionProjector } from "@opencode-ai/core/session/projector"
+import { Deferred, Effect, Exit, Layer } from "effect"
+import { Session as SessionNs } from "@/session/session"
+import { MessageV2 } from "../../src/session/message-v2"
+import { MessageID, PartID, type SessionID } from "../../src/session/schema"
+import { CrossSpawnSpawner } from "@opencode-ai/core/cross-spawn-spawner"
+import { provideInstance, testInstanceStoreLayer, tmpdirScoped } from "../fixture/fixture"
+import { testEffect } from "../lib/effect"
+import { Storage } from "@/storage/storage"
+import { RuntimeFlags } from "@/effect/runtime-flags"
+import { BackgroundJob } from "@/background/job"
+import { EventV2Bridge } from "@/event-v2-bridge"
+import { GlobalBus } from "@/bus/global"
+
+const it = testEffect(
+  Layer.mergeAll(
+    SessionNs.layer.pipe(
+      Layer.provide(Storage.defaultLayer),
+      Layer.provide(Database.defaultLayer),
+      Layer.provideMerge(EventV2Bridge.defaultLayer),
+      Layer.provide(SessionProjector.defaultLayer),
+      Layer.provide(RuntimeFlags.layer({ experimentalWorkspaces: false })),
+      Layer.provide(BackgroundJob.defaultLayer),
+    ),
+    CrossSpawnSpawner.defaultLayer,
+    testInstanceStoreLayer,
+  ),
+)
+
+const awaitDeferred = <T>(deferred: Deferred.Deferred<T>, message: string) =>
+  Effect.race(
+    Deferred.await(deferred),
+    Effect.sleep("2 seconds").pipe(Effect.flatMap(() => Effect.fail(new Error(message)))),
+  )
+
+const remove = (id: SessionID) => SessionNs.use.remove(id)
+
+describe("session.created event", () => {
+  it.instance("should emit session.created event when session is created", () =>
+    Effect.gen(function* () {
+      const session = yield* SessionNs.Service
+      const events = yield* EventV2Bridge.Service
+      const received = yield* Deferred.make<SessionNs.Info>()
+
+      const unsub = yield* events.listen((event) => {
+        if (event.type === SessionNs.Event.Created.type)
+          Deferred.doneUnsafe(
+            received,
+            Effect.succeed((event.data as typeof SessionNs.Event.Created.data.Type).info as SessionNs.Info),
+          )
+        return Effect.void
+      })
+      yield* Effect.addFinalizer(() => unsub)
+
+      const info = yield* session.create({})
+      const receivedInfo = yield* awaitDeferred(received, "timed out waiting for session.created")
+
+      expect(receivedInfo.id).toBe(info.id)
+      expect(receivedInfo.projectID).toBe(info.projectID)
+      expect(receivedInfo.directory).toBe(info.directory)
+      expect(receivedInfo.path).toBe(info.path)
+      expect(receivedInfo.title).toBe(info.title)
+
+      yield* session.remove(info.id)
+    }),
+  )
+
+  it.instance("session.created event should be emitted before session.updated", () =>
+    Effect.gen(function* () {
+      const session = yield* SessionNs.Service
+      const source = yield* EventV2Bridge.Service
+      const events: string[] = []
+      const received = yield* Deferred.make<string[]>()
+      const push = (event: string) => {
+        events.push(event)
+        if (events.includes("created") && events.includes("updated")) {
+          Deferred.doneUnsafe(received, Effect.succeed(events))
+        }
+      }
+
+      const unsubscribe = yield* source.listen((event) => {
+        if (event.type === SessionNs.Event.Created.type) push("created")
+        if (event.type === SessionNs.Event.Updated.type) push("updated")
+        return Effect.void
+      })
+      yield* Effect.addFinalizer(() => unsubscribe)
+
+      const info = yield* session.create({})
+      yield* session.setTitle({ sessionID: info.id, title: "updated" })
+      const receivedEvents = yield* awaitDeferred(received, "timed out waiting for session created/updated events")
+
+      expect(receivedEvents).toContain("created")
+      expect(receivedEvents).toContain("updated")
+      expect(receivedEvents.indexOf("created")).toBeLessThan(receivedEvents.indexOf("updated"))
+
+      yield* session.remove(info.id)
+    }),
+  )
+
+  it.instance("emits legacy global sync payload", () =>
+    Effect.gen(function* () {
+      const session = yield* SessionNs.Service
+      const received = yield* Deferred.make<{ syncEvent: EventV2.SerializedEvent }>()
+      const listener = (event: { payload: { type?: string; syncEvent?: EventV2.SerializedEvent } }) => {
+        if (event.payload.type === "sync" && event.payload.syncEvent)
+          Deferred.doneUnsafe(received, Effect.succeed({ syncEvent: event.payload.syncEvent }))
+      }
+      GlobalBus.on("event", listener)
+      yield* Effect.addFinalizer(() => Effect.sync(() => GlobalBus.off("event", listener)))
+
+      const info = yield* session.create({})
+      const event = yield* awaitDeferred(received, "timed out waiting for legacy global sync event")
+
+      expect(event.syncEvent).toMatchObject({
+        type: EventV2.versionedType(SessionNs.Event.Created.type, 1),
+        seq: 0,
+        aggregateID: info.id,
+        data: { sessionID: info.id },
+      })
+
+      yield* session.remove(info.id)
+    }),
+  )
+})
+
+describe("step-finish token propagation via event", () => {
+  it.instance(
+    "non-zero tokens propagate through PartUpdated event",
+    () =>
+      Effect.gen(function* () {
+        const session = yield* SessionNs.Service
+        const events = yield* EventV2Bridge.Service
+        const info = yield* session.create({})
+
+        const messageID = MessageID.ascending()
+        yield* session.updateMessage({
+          id: messageID,
+          sessionID: info.id,
+          role: "user",
+          time: { created: Date.now() },
+          agent: "user",
+          model: { providerID: "test", modelID: "test" },
+          tools: {},
+          mode: "",
+        } as unknown as SessionV1.Info)
+
+        // Event subscribers receive readonly Schema.Type payloads; `SessionV1.Part`
+        // is the mutable domain type. Cast bridges the two — safe because the
+        // test only reads the value afterwards.
+        const received = yield* Deferred.make<SessionV1.Part>()
+        const unsub = yield* events.listen((event) => {
+          if (event.type === MessageV2.Event.PartUpdated.type)
+            Deferred.doneUnsafe(
+              received,
+              Effect.succeed((event.data as typeof MessageV2.Event.PartUpdated.data.Type).part as SessionV1.Part),
+            )
+          return Effect.void
+        })
+        yield* Effect.addFinalizer(() => unsub)
+
+        const tokens = {
+          total: 1500,
+          input: 500,
+          output: 800,
+          reasoning: 200,
+          cache: { read: 100, write: 50 },
+        }
+
+        const partInput = {
+          id: PartID.ascending(),
+          messageID,
+          sessionID: info.id,
+          type: "step-finish" as const,
+          reason: "stop",
+          cost: 0.005,
+          tokens,
+        }
+
+        yield* session.updatePart(partInput)
+        const receivedPart = yield* awaitDeferred(received, "timed out waiting for message.part.updated")
+
+        expect(receivedPart.type).toBe("step-finish")
+        const finish = receivedPart as SessionV1.StepFinishPart
+        expect(finish.tokens.input).toBe(500)
+        expect(finish.tokens.output).toBe(800)
+        expect(finish.tokens.reasoning).toBe(200)
+        expect(finish.tokens.total).toBe(1500)
+        expect(finish.tokens.cache.read).toBe(100)
+        expect(finish.tokens.cache.write).toBe(50)
+        expect(finish.cost).toBe(0.005)
+        expect(receivedPart).not.toBe(partInput)
+
+        yield* session.remove(info.id)
+      }),
+    { timeout: 30000 },
+  )
+})
+
+describe("Session", () => {
+  it.live("remove works without an instance", () =>
+    Effect.gen(function* () {
+      const session = yield* SessionNs.Service
+      const dir = yield* tmpdirScoped({ git: true })
+      const info = yield* provideInstance(dir)(session.create({ title: "remove-without-instance" }))
+
+      const removeExit = yield* remove(info.id).pipe(Effect.exit)
+      expect(Exit.isSuccess(removeExit)).toBe(true)
+
+      const getExit = yield* session.get(info.id).pipe(Effect.exit)
+      expect(Exit.isFailure(getExit)).toBe(true)
+    }),
+  )
+
+  it.instance("persists metadata and copies it on fork by default", () =>
+    Effect.gen(function* () {
+      const session = yield* SessionNs.Service
+      const meta = { source: "sdk", trace: { id: "abc" } }
+      const created = yield* Effect.acquireRelease(session.create({ title: "with-meta", metadata: meta }), (info) =>
+        session.remove(info.id).pipe(Effect.ignore),
+      )
+      const saved = yield* session.get(created.id)
+      const fork = yield* Effect.acquireRelease(session.fork({ sessionID: created.id }), (info) =>
+        session.remove(info.id).pipe(Effect.ignore),
+      )
+
+      expect(saved.metadata).toEqual(meta)
+      expect(fork.metadata).toEqual(meta)
+      expect(fork.metadata).not.toBe(meta)
+    }),
+  )
+
+  it.instance("omits metadata when not provided", () =>
+    Effect.gen(function* () {
+      const session = yield* SessionNs.Service
+      const created = yield* Effect.acquireRelease(session.create({ title: "empty-meta" }), (info) =>
+        session.remove(info.id).pipe(Effect.ignore),
+      )
+      const saved = yield* session.get(created.id)
+
+      expect(created.metadata).toBeUndefined()
+      expect(saved.metadata).toBeUndefined()
+    }),
+  )
+})

packages/opencode/test/session/snapshot-tool-race.test.ts

@@ -0,0 +1,190 @@
+/**
+ * Reproducer for snapshot race condition with instant tool execution.
+ *
+ * When the mock LLM returns a tool call response instantly, the AI SDK
+ * processes the tool call and executes the tool (e.g. apply_patch) before
+ * the processor's start-step handler can capture a pre-tool snapshot.
+ * Both the "before" and "after" snapshots end up with the same git tree
+ * hash, so computeDiff returns empty and the session summary shows 0 files.
+ *
+ * This is a real bug: the snapshot system assumes it can capture state
+ * before tools run by hooking into start-step, but the AI SDK executes
+ * tools internally during multi-step processing before emitting events.
+ */
+import { expect } from "bun:test"
+import { Effect, Layer } from "effect"
+import { LayerNode } from "@opencode-ai/core/effect/layer-node"
+import fs from "fs/promises"
+import path from "path"
+import { Session } from "@/session/session"
+import { SessionPrompt } from "../../src/session/prompt"
+import { SessionSummary } from "../../src/session/summary"
+import { MessageV2 } from "../../src/session/message-v2"
+import { SessionV1 } from "@opencode-ai/core/v1/session"
+import { Database } from "@opencode-ai/core/database/database"
+import { SessionProjector } from "@opencode-ai/core/session/projector"
+import { provideTmpdirServer } from "../fixture/fixture"
+import { testEffect } from "../lib/effect"
+import { TestLLMServer } from "../lib/llm-server"
+
+import { LSP } from "@/lsp/lsp"
+import { MCP } from "../../src/mcp"
+import { CrossSpawnSpawner } from "@opencode-ai/core/cross-spawn-spawner"
+import { RuntimeFlags } from "@/effect/runtime-flags"
+
+const mcp = Layer.succeed(
+  MCP.Service,
+  MCP.Service.of({
+    status: () => Effect.succeed({}),
+    clients: () => Effect.succeed({}),
+    tools: () => Effect.succeed({}),
+    prompts: () => Effect.succeed({}),
+    resources: () => Effect.succeed({}),
+    add: () => Effect.succeed({ status: { status: "disabled" as const } }),
+    connect: () => Effect.void,
+    disconnect: () => Effect.void,
+    getPrompt: () => Effect.succeed(undefined),
+    readResource: () => Effect.succeed(undefined),
+    startAuth: () => Effect.die("unexpected MCP auth"),
+    authenticate: () => Effect.die("unexpected MCP auth"),
+    finishAuth: () => Effect.die("unexpected MCP auth"),
+    removeAuth: () => Effect.void,
+    supportsOAuth: () => Effect.succeed(false),
+    hasStoredTokens: () => Effect.succeed(false),
+    getAuthStatus: () => Effect.succeed("not_authenticated" as const),
+  }),
+)
+
+const lsp = Layer.succeed(
+  LSP.Service,
+  LSP.Service.of({
+    init: () => Effect.void,
+    status: () => Effect.succeed([]),
+    hasClients: () => Effect.succeed(false),
+    touchFile: () => Effect.void,
+    diagnostics: () => Effect.succeed({}),
+    hover: () => Effect.succeed(undefined),
+    definition: () => Effect.succeed([]),
+    references: () => Effect.succeed([]),
+    implementation: () => Effect.succeed([]),
+    documentSymbol: () => Effect.succeed([]),
+    workspaceSymbol: () => Effect.succeed([]),
+    prepareCallHierarchy: () => Effect.succeed([]),
+    incomingCalls: () => Effect.succeed([]),
+    outgoingCalls: () => Effect.succeed([]),
+  }),
+)
+
+const root = LayerNode.group([
+  SessionPrompt.node,
+  Session.node,
+  SessionProjector.node,
+  SessionSummary.node,
+  Database.node,
+  CrossSpawnSpawner.node,
+  LayerNode.make(TestLLMServer.layer, []),
+])
+const it = testEffect(
+  LayerNode.buildLayer(root, {
+    replacements: [
+      LayerNode.replace(MCP.node, mcp),
+      LayerNode.replace(LSP.node, lsp),
+      LayerNode.replace(RuntimeFlags.node, RuntimeFlags.layer({ experimentalEventSystem: true })),
+    ],
+  }),
+)
+
+const providerCfg = (url: string) => ({
+  provider: {
+    test: {
+      name: "Test",
+      id: "test",
+      env: [],
+      npm: "@ai-sdk/openai-compatible",
+      models: {
+        "test-model": {
+          id: "test-model",
+          name: "Test Model",
+          attachment: false,
+          reasoning: false,
+          temperature: false,
+          tool_call: true,
+          release_date: "2025-01-01",
+          limit: { context: 100000, output: 10000 },
+          cost: { input: 0, output: 0 },
+          options: {},
+        },
+      },
+      options: {
+        apiKey: "test-key",
+        baseURL: url,
+      },
+    },
+  },
+})
+
+it.live("tool execution produces non-empty session diff (snapshot race)", () =>
+  provideTmpdirServer(
+    Effect.fnUntraced(function* ({ dir, llm }) {
+      const prompt = yield* SessionPrompt.Service
+      const sessions = yield* Session.Service
+      const summary = yield* SessionSummary.Service
+
+      const session = yield* sessions.create({
+        title: "snapshot race test",
+        permission: [{ permission: "*", pattern: "*", action: "allow" }],
+      })
+
+      // Use bash tool (always registered) to create a file
+      const command = `echo 'snapshot race test content' > ${path.join(dir, "race-test.txt")}`
+      yield* llm.toolMatch((hit) => JSON.stringify(hit.body).includes("create the file"), "bash", {
+        command,
+        description: "create test file",
+      })
+      yield* llm.textMatch((hit) => JSON.stringify(hit.body).includes("bash"), "done")
+
+      // Seed user message
+      yield* prompt.prompt({
+        sessionID: session.id,
+        agent: "build",
+        noReply: true,
+        parts: [{ type: "text", text: "create the file" }],
+      })
+
+      // Run the agent loop
+      const result = yield* prompt.loop({ sessionID: session.id })
+      expect(result.info.role).toBe("assistant")
+
+      // Verify the file was created
+      const filePath = path.join(dir, "race-test.txt")
+      const fileExists = yield* Effect.promise(() =>
+        fs
+          .access(filePath)
+          .then(() => true)
+          .catch(() => false),
+      )
+      expect(fileExists).toBe(true)
+
+      // Verify the tool call completed (in the first assistant message)
+      const allMsgs = yield* MessageV2.filterCompactedEffect(session.id)
+      const user = allMsgs.find(
+        (msg): msg is SessionV1.WithParts & { info: SessionV1.User } => msg.info.role === "user",
+      )
+      const tool = allMsgs
+        .flatMap((m) => m.parts)
+        .find((p): p is SessionV1.ToolPart => p.type === "tool" && p.tool === "bash")
+      expect(tool?.state.status).toBe("completed")
+      if (!user) throw new Error("Expected user message")
+
+      // Poll for the turn diff — summarize() is fire-and-forget.
+      let diff: Array<{ file?: string }> = []
+      for (let i = 0; i < 50; i++) {
+        diff = yield* summary.diff({ sessionID: session.id, messageID: user.info.id })
+        if (diff.length > 0) break
+        yield* Effect.sleep("100 millis")
+      }
+      expect(diff.length).toBeGreaterThan(0)
+    }),
+    { git: true, config: providerCfg },
+  ),
+)

packages/opencode/test/session/structured-output-integration.test.ts

@@ -0,0 +1,235 @@
+import { describe, expect, test } from "bun:test"
+import { SessionV1 } from "@opencode-ai/core/v1/session"
+import { Ripgrep } from "@opencode-ai/core/ripgrep"
+import { Effect, Layer } from "effect"
+import { Session } from "@/session/session"
+import { SessionPrompt } from "../../src/session/prompt"
+import { MessageV2 } from "../../src/session/message-v2"
+import { testEffect } from "../lib/effect"
+
+// Skip tests if no API key is available
+const hasApiKey = !!process.env.ANTHROPIC_API_KEY
+const it = testEffect(
+  Layer.mergeAll(SessionPrompt.defaultLayer, Session.defaultLayer).pipe(Layer.provide(Ripgrep.defaultLayer)),
+)
+const live = hasApiKey ? it.instance : it.instance.skip
+
+describe("StructuredOutput Integration", () => {
+  live(
+    "produces structured output with simple schema",
+    () =>
+      Effect.gen(function* () {
+        const prompt = yield* SessionPrompt.Service
+        const sessions = yield* Session.Service
+        const session = yield* sessions.create({ title: "Structured Output Test" })
+
+        const result = yield* prompt.prompt({
+          sessionID: session.id,
+          parts: [
+            {
+              type: "text",
+              text: "What is 2 + 2? Provide a simple answer.",
+            },
+          ],
+          format: {
+            type: "json_schema",
+            schema: {
+              type: "object",
+              properties: {
+                answer: { type: "number", description: "The numerical answer" },
+                explanation: { type: "string", description: "Brief explanation" },
+              },
+              required: ["answer"],
+            },
+            retryCount: 0,
+          },
+        })
+
+        // Verify structured output was captured (only on assistant messages)
+        expect(result.info.role).toBe("assistant")
+        if (result.info.role === "assistant") {
+          expect(result.info.structured).toBeDefined()
+          expect(typeof result.info.structured).toBe("object")
+
+          const output = result.info.structured as any
+          expect(output.answer).toBe(4)
+
+          // Verify no error was set
+          expect(result.info.error).toBeUndefined()
+        }
+
+        // Clean up
+        // Note: Not removing session to avoid race with background SessionSummary.summarize
+      }),
+    { git: true },
+    60000,
+  )
+
+  live(
+    "produces structured output with nested objects",
+    () =>
+      Effect.gen(function* () {
+        const prompt = yield* SessionPrompt.Service
+        const sessions = yield* Session.Service
+        const session = yield* sessions.create({ title: "Nested Schema Test" })
+
+        const result = yield* prompt.prompt({
+          sessionID: session.id,
+          parts: [
+            {
+              type: "text",
+              text: "Tell me about Anthropic company in a structured format.",
+            },
+          ],
+          format: {
+            type: "json_schema",
+            schema: {
+              type: "object",
+              properties: {
+                company: {
+                  type: "object",
+                  properties: {
+                    name: { type: "string" },
+                    founded: { type: "number" },
+                  },
+                  required: ["name", "founded"],
+                },
+                products: {
+                  type: "array",
+                  items: { type: "string" },
+                },
+              },
+              required: ["company"],
+            },
+            retryCount: 0,
+          },
+        })
+
+        // Verify structured output was captured (only on assistant messages)
+        expect(result.info.role).toBe("assistant")
+        if (result.info.role === "assistant") {
+          expect(result.info.structured).toBeDefined()
+          const output = result.info.structured as any
+
+          expect(output.company).toBeDefined()
+          expect(output.company.name).toBe("Anthropic")
+          expect(typeof output.company.founded).toBe("number")
+
+          if (output.products) {
+            expect(Array.isArray(output.products)).toBe(true)
+          }
+
+          // Verify no error was set
+          expect(result.info.error).toBeUndefined()
+        }
+
+        // Clean up
+        // Note: Not removing session to avoid race with background SessionSummary.summarize
+      }),
+    { git: true },
+    60000,
+  )
+
+  live(
+    "works with text outputFormat (default)",
+    () =>
+      Effect.gen(function* () {
+        const prompt = yield* SessionPrompt.Service
+        const sessions = yield* Session.Service
+        const session = yield* sessions.create({ title: "Text Output Test" })
+
+        const result = yield* prompt.prompt({
+          sessionID: session.id,
+          parts: [
+            {
+              type: "text",
+              text: "Say hello.",
+            },
+          ],
+          format: {
+            type: "text",
+          },
+        })
+
+        // Verify no structured output (text mode) and no error
+        expect(result.info.role).toBe("assistant")
+        if (result.info.role === "assistant") {
+          expect(result.info.structured).toBeUndefined()
+          expect(result.info.error).toBeUndefined()
+        }
+
+        // Verify we got a response with parts
+        expect(result.parts.length).toBeGreaterThan(0)
+
+        // Clean up
+        // Note: Not removing session to avoid race with background SessionSummary.summarize
+      }),
+    { git: true },
+    60000,
+  )
+
+  live(
+    "stores outputFormat on user message",
+    () =>
+      Effect.gen(function* () {
+        const prompt = yield* SessionPrompt.Service
+        const sessions = yield* Session.Service
+        const session = yield* sessions.create({ title: "OutputFormat Storage Test" })
+
+        yield* prompt.prompt({
+          sessionID: session.id,
+          parts: [
+            {
+              type: "text",
+              text: "What is 1 + 1?",
+            },
+          ],
+          format: {
+            type: "json_schema",
+            schema: {
+              type: "object",
+              properties: {
+                result: { type: "number" },
+              },
+              required: ["result"],
+            },
+            retryCount: 3,
+          },
+        })
+
+        // Get all messages from session
+        const messages = yield* sessions.messages({ sessionID: session.id })
+        const userMessage = messages.find((m) => m.info.role === "user")
+
+        // Verify outputFormat was stored on user message
+        expect(userMessage).toBeDefined()
+        if (userMessage?.info.role === "user") {
+          expect(userMessage.info.format).toBeDefined()
+          expect(userMessage.info.format?.type).toBe("json_schema")
+          if (userMessage.info.format?.type === "json_schema") {
+            expect(userMessage.info.format.retryCount).toBe(3)
+          }
+        }
+
+        // Clean up
+        // Note: Not removing session to avoid race with background SessionSummary.summarize
+      }),
+    { git: true },
+    60000,
+  )
+
+  test("unit test: StructuredOutputError is properly structured", () => {
+    const error = new SessionV1.StructuredOutputError({
+      message: "Failed to produce valid structured output after 3 attempts",
+      retries: 3,
+    })
+
+    expect(error.name).toBe("StructuredOutputError")
+    expect(error.data.message).toContain("3 attempts")
+    expect(error.data.retries).toBe(3)
+
+    const obj = error.toObject()
+    expect(obj.name).toBe("StructuredOutputError")
+    expect(obj.data.retries).toBe(3)
+  })
+})

packages/opencode/test/session/structured-output.test.ts

@@ -0,0 +1,387 @@
+import { describe, expect, test } from "bun:test"
+import { SessionV1 } from "@opencode-ai/core/v1/session"
+import { Exit, Schema } from "effect"
+import { MessageV2 } from "../../src/session/message-v2"
+import { SessionPrompt } from "../../src/session/prompt"
+import { SessionID, MessageID } from "../../src/session/schema"
+
+const decodeFormat = Schema.decodeUnknownExit(SessionV1.Format)
+const decodeUser = Schema.decodeUnknownExit(SessionV1.User)
+const decodeAssistant = Schema.decodeUnknownExit(SessionV1.Assistant)
+
+describe("structured-output.OutputFormat", () => {
+  test("parses text format", () => {
+    const result = decodeFormat({ type: "text" })
+    expect(Exit.isSuccess(result)).toBe(true)
+    if (Exit.isSuccess(result)) {
+      expect(result.value.type).toBe("text")
+    }
+  })
+
+  test("parses json_schema format with defaults", () => {
+    const result = decodeFormat({
+      type: "json_schema",
+      schema: { type: "object", properties: { name: { type: "string" } } },
+    })
+    expect(Exit.isSuccess(result)).toBe(true)
+    if (Exit.isSuccess(result)) {
+      expect(result.value.type).toBe("json_schema")
+      if (result.value.type === "json_schema") {
+        expect(result.value.retryCount).toBe(2) // default value
+      }
+    }
+  })
+
+  test("parses json_schema format with custom retryCount", () => {
+    const result = decodeFormat({
+      type: "json_schema",
+      schema: { type: "object" },
+      retryCount: 5,
+    })
+    expect(Exit.isSuccess(result)).toBe(true)
+    if (Exit.isSuccess(result) && result.value.type === "json_schema") {
+      expect(result.value.retryCount).toBe(5)
+    }
+  })
+
+  test("rejects invalid type", () => {
+    const result = decodeFormat({ type: "invalid" })
+    expect(Exit.isFailure(result)).toBe(true)
+  })
+
+  test("rejects json_schema without schema", () => {
+    const result = decodeFormat({ type: "json_schema" })
+    expect(Exit.isFailure(result)).toBe(true)
+  })
+
+  test("rejects negative retryCount", () => {
+    const result = decodeFormat({
+      type: "json_schema",
+      schema: { type: "object" },
+      retryCount: -1,
+    })
+    expect(Exit.isFailure(result)).toBe(true)
+  })
+})
+
+describe("structured-output.StructuredOutputError", () => {
+  test("creates error with message and retries", () => {
+    const error = new SessionV1.StructuredOutputError({
+      message: "Failed to validate",
+      retries: 3,
+    })
+
+    expect(error.name).toBe("StructuredOutputError")
+    expect(error.data.message).toBe("Failed to validate")
+    expect(error.data.retries).toBe(3)
+  })
+
+  test("converts to object correctly", () => {
+    const error = new SessionV1.StructuredOutputError({
+      message: "Test error",
+      retries: 2,
+    })
+
+    const obj = error.toObject()
+    expect(obj.name).toBe("StructuredOutputError")
+    expect(obj.data.message).toBe("Test error")
+    expect(obj.data.retries).toBe(2)
+  })
+
+  test("isInstance correctly identifies error", () => {
+    const error = new SessionV1.StructuredOutputError({
+      message: "Test",
+      retries: 1,
+    })
+
+    expect(SessionV1.StructuredOutputError.isInstance(error)).toBe(true)
+    expect(SessionV1.StructuredOutputError.isInstance({ name: "other" })).toBe(false)
+  })
+})
+
+describe("structured-output.UserMessage", () => {
+  test("user message accepts outputFormat", () => {
+    const result = decodeUser({
+      id: MessageID.ascending(),
+      sessionID: SessionID.descending(),
+      role: "user",
+      time: { created: Date.now() },
+      agent: "default",
+      model: { providerID: "anthropic", modelID: "claude-3" },
+      outputFormat: {
+        type: "json_schema",
+        schema: { type: "object" },
+      },
+    })
+    expect(Exit.isSuccess(result)).toBe(true)
+  })
+
+  test("user message works without outputFormat (optional)", () => {
+    const result = decodeUser({
+      id: MessageID.ascending(),
+      sessionID: SessionID.descending(),
+      role: "user",
+      time: { created: Date.now() },
+      agent: "default",
+      model: { providerID: "anthropic", modelID: "claude-3" },
+    })
+    expect(Exit.isSuccess(result)).toBe(true)
+  })
+})
+
+describe("structured-output.AssistantMessage", () => {
+  const baseAssistantMessage = {
+    id: MessageID.ascending(),
+    sessionID: SessionID.descending(),
+    role: "assistant" as const,
+    parentID: MessageID.ascending(),
+    modelID: "claude-3",
+    providerID: "anthropic",
+    mode: "default",
+    agent: "default",
+    path: { cwd: "/test", root: "/test" },
+    cost: 0.001,
+    tokens: { input: 100, output: 50, reasoning: 0, cache: { read: 0, write: 0 } },
+    time: { created: Date.now() },
+  }
+
+  test("assistant message accepts structured", () => {
+    const result = decodeAssistant({
+      ...baseAssistantMessage,
+      structured: { company: "Anthropic", founded: 2021 },
+    })
+    expect(Exit.isSuccess(result)).toBe(true)
+    if (Exit.isSuccess(result)) {
+      expect(result.value.structured).toEqual({ company: "Anthropic", founded: 2021 })
+    }
+  })
+
+  test("assistant message works without structured_output (optional)", () => {
+    const result = decodeAssistant(baseAssistantMessage)
+    expect(Exit.isSuccess(result)).toBe(true)
+  })
+})
+
+describe("structured-output.createStructuredOutputTool", () => {
+  test("creates tool with description", () => {
+    const tool = SessionPrompt.createStructuredOutputTool({
+      schema: { type: "object" },
+      onSuccess: () => {},
+    })
+
+    expect(tool.description).toContain("structured format")
+  })
+
+  test("creates tool with schema as inputSchema", () => {
+    const schema = {
+      type: "object",
+      properties: {
+        company: { type: "string" },
+        founded: { type: "number" },
+      },
+      required: ["company"],
+    }
+
+    const tool = SessionPrompt.createStructuredOutputTool({
+      schema,
+      onSuccess: () => {},
+    })
+
+    // AI SDK wraps schema in { jsonSchema: {...} }
+    expect(tool.inputSchema).toBeDefined()
+    const inputSchema = tool.inputSchema as any
+    expect(inputSchema.jsonSchema?.properties?.company).toBeDefined()
+    expect(inputSchema.jsonSchema?.properties?.founded).toBeDefined()
+  })
+
+  test("strips $schema property from inputSchema", () => {
+    const schema = {
+      $schema: "http://json-schema.org/draft-07/schema#",
+      type: "object",
+      properties: { name: { type: "string" } },
+    }
+
+    const tool = SessionPrompt.createStructuredOutputTool({
+      schema,
+      onSuccess: () => {},
+    })
+
+    // AI SDK wraps schema in { jsonSchema: {...} }
+    const inputSchema = tool.inputSchema as any
+    expect(inputSchema.jsonSchema?.$schema).toBeUndefined()
+  })
+
+  test("execute calls onSuccess with valid args", async () => {
+    let capturedOutput: unknown
+
+    const tool = SessionPrompt.createStructuredOutputTool({
+      schema: { type: "object", properties: { name: { type: "string" } } },
+      onSuccess: (output) => {
+        capturedOutput = output
+      },
+    })
+
+    expect(tool.execute).toBeDefined()
+    const testArgs = { name: "Test Company" }
+    const result = await tool.execute!(testArgs, {
+      toolCallId: "test-call-id",
+      messages: [],
+      abortSignal: undefined as any,
+    })
+
+    expect(capturedOutput).toEqual(testArgs)
+    expect(result.output).toBe("Structured output captured successfully.")
+    expect(result.metadata.valid).toBe(true)
+  })
+
+  test("AI SDK validates schema before execute - missing required field", async () => {
+    // Note: The AI SDK validates the input against the schema BEFORE calling execute()
+    // So invalid inputs never reach the tool's execute function
+    // This test documents the expected schema behavior
+    const tool = SessionPrompt.createStructuredOutputTool({
+      schema: {
+        type: "object",
+        properties: {
+          name: { type: "string" },
+          age: { type: "number" },
+        },
+        required: ["name", "age"],
+      },
+      onSuccess: () => {},
+    })
+
+    // The schema requires both 'name' and 'age'
+    expect(tool.inputSchema).toBeDefined()
+    const inputSchema = tool.inputSchema as any
+    expect(inputSchema.jsonSchema?.required).toContain("name")
+    expect(inputSchema.jsonSchema?.required).toContain("age")
+  })
+
+  test("AI SDK validates schema types before execute - wrong type", async () => {
+    // Note: The AI SDK validates the input against the schema BEFORE calling execute()
+    // So invalid inputs never reach the tool's execute function
+    // This test documents the expected schema behavior
+    const tool = SessionPrompt.createStructuredOutputTool({
+      schema: {
+        type: "object",
+        properties: {
+          count: { type: "number" },
+        },
+        required: ["count"],
+      },
+      onSuccess: () => {},
+    })
+
+    // The schema defines 'count' as a number
+    expect(tool.inputSchema).toBeDefined()
+    const inputSchema = tool.inputSchema as any
+    expect(inputSchema.jsonSchema?.properties?.count?.type).toBe("number")
+  })
+
+  test("execute handles nested objects", async () => {
+    let capturedOutput: unknown
+
+    const tool = SessionPrompt.createStructuredOutputTool({
+      schema: {
+        type: "object",
+        properties: {
+          user: {
+            type: "object",
+            properties: {
+              name: { type: "string" },
+              email: { type: "string" },
+            },
+            required: ["name"],
+          },
+        },
+        required: ["user"],
+      },
+      onSuccess: (output) => {
+        capturedOutput = output
+      },
+    })
+
+    // Valid nested object - AI SDK validates before calling execute()
+    const validResult = await tool.execute!(
+      { user: { name: "John", email: "john@test.com" } },
+      {
+        toolCallId: "test-call-id",
+        messages: [],
+        abortSignal: undefined as any,
+      },
+    )
+
+    expect(capturedOutput).toEqual({ user: { name: "John", email: "john@test.com" } })
+    expect(validResult.metadata.valid).toBe(true)
+
+    // Verify schema has correct nested structure
+    const inputSchema = tool.inputSchema as any
+    expect(inputSchema.jsonSchema?.properties?.user?.type).toBe("object")
+    expect(inputSchema.jsonSchema?.properties?.user?.properties?.name?.type).toBe("string")
+    expect(inputSchema.jsonSchema?.properties?.user?.required).toContain("name")
+  })
+
+  test("execute handles arrays", async () => {
+    let capturedOutput: unknown
+
+    const tool = SessionPrompt.createStructuredOutputTool({
+      schema: {
+        type: "object",
+        properties: {
+          tags: {
+            type: "array",
+            items: { type: "string" },
+          },
+        },
+        required: ["tags"],
+      },
+      onSuccess: (output) => {
+        capturedOutput = output
+      },
+    })
+
+    // Valid array - AI SDK validates before calling execute()
+    const validResult = await tool.execute!(
+      { tags: ["a", "b", "c"] },
+      {
+        toolCallId: "test-call-id",
+        messages: [],
+        abortSignal: undefined as any,
+      },
+    )
+
+    expect(capturedOutput).toEqual({ tags: ["a", "b", "c"] })
+    expect(validResult.metadata.valid).toBe(true)
+
+    // Verify schema has correct array structure
+    const inputSchema = tool.inputSchema as any
+    expect(inputSchema.jsonSchema?.properties?.tags?.type).toBe("array")
+    expect(inputSchema.jsonSchema?.properties?.tags?.items?.type).toBe("string")
+  })
+
+  test("toModelOutput returns text value", async () => {
+    const tool = SessionPrompt.createStructuredOutputTool({
+      schema: { type: "object" },
+      onSuccess: () => {},
+    })
+
+    expect(tool.toModelOutput).toBeDefined()
+    const modelOutput = await Promise.resolve(
+      tool.toModelOutput!({
+        toolCallId: "test-call-id",
+        input: {},
+        output: {
+          output: "Test output",
+        },
+      }),
+    )
+
+    expect(modelOutput.type).toBe("text")
+    if (modelOutput.type !== "text") throw new Error("expected text model output")
+    expect(modelOutput.value).toBe("Test output")
+  })
+
+  // Note: Retry behavior is handled by the AI SDK and the prompt loop, not the tool itself
+  // The tool simply calls onSuccess when execute() is called with valid args
+  // See prompt.ts loop() for actual retry logic
+})

packages/opencode/test/session/system.test.ts

@@ -0,0 +1,86 @@
+import { describe, expect } from "bun:test"
+import { Effect, Layer } from "effect"
+import type { Agent } from "../../src/agent/agent"
+import { NamedError } from "@opencode-ai/core/util/error"
+import { Skill } from "../../src/skill"
+import { Permission } from "../../src/permission"
+import { SystemPrompt } from "../../src/session/system"
+import { LocationServiceMap } from "@opencode-ai/core/location-layer"
+import { testEffect } from "../lib/effect"
+
+const skills: Skill.Info[] = [
+  {
+    name: "zeta-skill",
+    description: "Zeta skill.",
+    location: "/tmp/zeta-skill/SKILL.md",
+    content: "# zeta-skill",
+  },
+  {
+    name: "alpha-skill",
+    description: "Alpha skill.",
+    location: "/tmp/alpha-skill/SKILL.md",
+    content: "# alpha-skill",
+  },
+  {
+    name: "middle-skill",
+    description: "Middle skill.",
+    location: "/tmp/middle-skill/SKILL.md",
+    content: "# middle-skill",
+  },
+  {
+    name: "manual-skill",
+    location: "/tmp/manual-skill/SKILL.md",
+    content: "# manual-skill",
+  },
+]
+
+const build: Agent.Info = {
+  name: "build",
+  mode: "primary",
+  permission: Permission.fromConfig({ "*": "allow" }),
+  options: {},
+}
+
+const it = testEffect(
+  SystemPrompt.layer.pipe(
+    Layer.provide(LocationServiceMap.layer),
+    Layer.provide(
+      Layer.succeed(
+        Skill.Service,
+        Skill.Service.of({
+          get: (name) => Effect.succeed(skills.find((skill) => skill.name === name)),
+          require: (name) => {
+            const info = skills.find((skill) => skill.name === name)
+            if (info) return Effect.succeed(info)
+            return Effect.fail(new Skill.NotFoundError({ name, available: skills.map((skill) => skill.name) }))
+          },
+          all: () => Effect.succeed(skills),
+          dirs: () => Effect.succeed([]),
+          available: () => Effect.succeed(skills),
+        }),
+      ),
+    ),
+  ),
+)
+
+describe("session.system", () => {
+  it.effect("skills output is sorted by name and stable across calls", () =>
+    Effect.gen(function* () {
+      const prompt = yield* SystemPrompt.Service
+      const first = yield* prompt.skills(build)
+      const second = yield* prompt.skills(build)
+      const output = first ?? (yield* Effect.fail(new NamedError.Unknown({ message: "missing skills output" })))
+
+      expect(first).toBe(second)
+
+      const alpha = output.indexOf("<name>alpha-skill</name>")
+      const middle = output.indexOf("<name>middle-skill</name>")
+      const zeta = output.indexOf("<name>zeta-skill</name>")
+
+      expect(alpha).toBeGreaterThan(-1)
+      expect(middle).toBeGreaterThan(alpha)
+      expect(zeta).toBeGreaterThan(middle)
+      expect(output).not.toContain("manual-skill")
+    }),
+  )
+})