fix: address review feedback (星月) for Phase 3

1. sendToWorker: IPC send failure now marks thread as failed + dequeues next
2. crashLimitBlocked Set: prevents new startWorkflow from bypassing crash limit
3. "respawning" log skipped when crash limit is active
4. logWorkflowEvent payload: unknown | null (project convention, not ?:)

.knowledge/adapter.md

@@ -28,8 +28,29 @@ For long-running or incremental agent outputs:
 |---------|---------|------|
 | `@uncaged/nerve-adapter-cursor` | `cursorAdapter` / `createCursorAdapter()` | cursor-agent CLI |
 | `@uncaged/nerve-adapter-hermes` | `hermesAdapter` / `createHermesAdapter()` | hermes chat CLI |
+| `@uncaged/nerve-workflow-utils` | `createLlmAdapter(provider)` | OpenAI-compatible HTTP chat (single-turn) |
 
-Each exports a **default instance** (sensible defaults) and a **factory** for custom config.
+The Cursor and Hermes adapter packages each export a **default instance** (sensible defaults) and a **factory** for custom config. `createLlmAdapter` is a factory on `@uncaged/nerve-workflow-utils` only.
+
+## createLlmAdapter
+
+`createLlmAdapter` builds an `AgentFn` from an `LlmProvider` (`baseUrl`, `apiKey`, `model`). One chat completion per role step: **system** = the string passed by `createRole` (your prompt); **user** = `ctx.start.content` (the thread’s start frame). On failure it throws with a formatted LLM error.
+
+```ts
+import { createLlmAdapter, createRole } from "@uncaged/nerve-workflow-utils";
+import { z } from "zod";
+
+const metaSchema = z.object({ ok: z.boolean() });
+
+const planner = createRole(
+  createLlmAdapter({ baseUrl: "https://api.example.com/v1", apiKey: "…", model: "gpt-4o-mini" }),
+  "You are a planner…",
+  metaSchema,
+  extractConfig,
+);
+```
+
+Use this when you want a role backed by an HTTP LLM instead of a subprocess CLI adapter.
 
 ## Usage in Workflows
 

.knowledge/workflow.md

@@ -2,6 +2,20 @@
 
 Stateful multi-step execution driven by Roles and a Moderator.
 
+## Workspace Layout (authoring)
+
+User Nerve workspaces use a **flat** build: one root `package.json`, one root bundle script (typically `scripts/build.mjs` wired from `scripts.build`), and **no** per-workflow `package.json` or `tsconfig.json`.
+
+| Location | Purpose |
+|----------|---------|
+| `workflows/<name>/index.ts` | Default export: `WorkflowDefinition` (moderator + role map). |
+| `workflows/<name>/roles/<role>.ts` | One module per role — schemas, prompts, `createRole` factories, or hand-written async role functions. |
+| `dist/workflows/<name>/index.js` | Emit of the root build; this is what the daemon loads. |
+
+**Naming:** Workflow ids should be **verb-first** kebab-case phrases (e.g. `deploy-staging`, `scan-dependencies`), not opaque nouns alone.
+
+Senses follow the same flat pattern: `senses/<name>/src/*.ts`, `migrations/`, root build → `dist/senses/<name>/index.js`. See `.knowledge/sense.md`.
+
 ## Core Concepts
 
 - **Workflow** — definition with concurrency strategy

packages/cli/src/__tests__/e2e-validate-init.test.ts

@@ -205,6 +205,10 @@ describe("e2e init", () => {
     expect(existsSync(join(nerveRoot, "scripts", "build.mjs"))).toBe(true);
     expect(existsSync(join(nerveRoot, "biome.json"))).toBe(true);
     expect(existsSync(join(nerveRoot, ".gitignore"))).toBe(true);
+    expect(existsSync(join(nerveRoot, "AGENT.md"))).toBe(true);
+    const agentMd = readFileSync(join(nerveRoot, "AGENT.md"), "utf8");
+    expect(agentMd).toContain("verb-first");
+    expect(agentMd).toContain("createRole");
     expect(existsSync(join(nerveRoot, "senses", "cpu-usage", "src", "index.ts"))).toBe(true);
     expect(existsSync(join(nerveRoot, "senses", "cpu-usage", "src", "schema.ts"))).toBe(true);
     expect(existsSync(join(nerveRoot, "senses", "cpu-usage", "migrations", "0001_init.sql"))).toBe(

packages/cli/src/commands/init.ts

@@ -127,6 +127,70 @@ node_modules/
 knowledge.db
 `;
 
+/** Generated at workspace root so agents can \`cat AGENT.md\` instead of npm skill paths. */
+const AGENT_MD = `# Nerve workspace — agent guide
+
+This file is created by \`nerve init\`. Read it before implementing senses or workflows.
+
+## Directory layout
+
+| Path | Purpose |
+|------|---------|
+| \`nerve.yaml\` | Senses, workflows, intervals, groups |
+| \`package.json\` | Single root package — no per-sense/per-workflow packages |
+| \`scripts/build.mjs\` | Root esbuild step; output under \`dist/\` |
+| \`senses/<name>/src/index.ts\` | Sense \`compute()\` entry |
+| \`senses/<name>/src/schema.ts\` | Drizzle SQLite schema (TypeScript) |
+| \`senses/<name>/migrations/*.sql\` | SQL migrations (next to \`src/\`, not inside it) |
+| \`workflows/<name>/index.ts\` | Default export: \`WorkflowDefinition\` |
+| \`workflows/<name>/roles/<role>.ts\` | One TypeScript file per role |
+| \`dist/senses/<name>/index.js\` | Bundled sense (after build) |
+| \`dist/workflows/<name>/index.js\` | Bundled workflow (after build) |
+
+There is **no** \`package.json\` or \`tsconfig.json\` inside individual senses or workflows.
+
+## Naming
+
+- **Workflows:** verb-first kebab-case (e.g. \`review-pull-request\`, \`deploy-staging\`). Avoid bare nouns like \`notifications\`.
+- **Senses:** kebab-case descriptive nouns (e.g. \`cpu-usage\`).
+
+## Workflow roles — four-tuple pattern
+
+Wire each role with \`createRole\` from \`@uncaged/nerve-workflow-utils\`:
+
+1. **Adapter** — \`AgentFn\` (LLM call)
+2. **Prompt builder** — \`async (ctx: ThreadContext) => string\`
+3. **Meta schema** — Zod object (routing / structured output from the model)
+4. **Extractor config** — how JSON meta is parsed from replies
+
+Keep meta small (often one boolean per role). The **moderator** in \`WorkflowDefinition\` routes between role names.
+
+## Build commands
+
+Always run from the **workspace root**:
+
+\`\`\`bash
+pnpm run build
+# or: npm run build
+\`\`\`
+
+Fix errors until this succeeds. New workflows must appear under \`workflows/<name>/\` and be registered in \`nerve.yaml\`; new senses under \`senses/<name>/\` with matching \`nerve.yaml\` entries.
+
+## Coding style (Nerve conventions)
+
+- Use \`type\`, not \`interface\`; prefer \`function\` over classes (except errors / library requirements).
+- **Named exports only** — no \`export default\` (exception: \`workflows/<name>/index.ts\` uses default export for the daemon loader).
+- Nullable fields: \`T | null\`, not TypeScript optional \`?:\`.
+- No dynamic \`import()\` in workspace code (bundling and tooling assume static imports).
+- Use \`async\`/\`await\`; use a \`Result\` type for expected failures instead of control-flow try/catch.
+
+## Extra references (optional)
+
+- \`CONVENTIONS.md\` — project-specific overrides at repo root.
+- \`.knowledge/*.md\` — deeper docs when working inside the Nerve monorepo.
+- \`.cursor/skills/\` — Cursor Agent Skills (\`SKILL.md\` per skill).
+`;
+
 const NERVE_SKILLS_MDC = `---
 description: >-
   Where Agent Skills live in this Nerve workspace and how to use them with Cursor
@@ -362,6 +426,7 @@ async function runInitWorkspace(force: boolean, skipInstall = false): Promise<vo
   writeFile(join(nerveRoot, "scripts", "build.mjs"), BUILD_MJS);
   writeFile(join(nerveRoot, "biome.json"), BIOME_JSON);
   writeFile(join(nerveRoot, ".gitignore"), GITIGNORE);
+  writeFile(join(nerveRoot, "AGENT.md"), AGENT_MD);
   writeFile(join(nerveRoot, "senses", "cpu-usage", "src", "index.ts"), CPU_INDEX_TS);
   writeFile(join(nerveRoot, "senses", "cpu-usage", "src", "schema.ts"), CPU_SCHEMA_TS);
   writeFile(

packages/daemon/src/__tests__/crash-recovery.test.ts

@@ -28,6 +28,11 @@ function makeMockChild(pid = 1): MockChild {
   child.connected = true;
   child.exitCode = null;
   child.pid = pid;
+  setImmediate(() => {
+    if (child.connected) {
+      child.emit("message", { type: "ready" });
+    }
+  });
   child.send = vi.fn((msg: unknown) => {
     if (
       msg !== null &&
@@ -132,6 +137,7 @@ describe("WorkflowManager — crash recovery (Phase 3)", () => {
 
       mgr.startWorkflow("my-wf", { prompt: "test 1", maxRounds: 10, dryRun: false });
       mgr.startWorkflow("my-wf", { prompt: "test 2", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
       expect(mgr.activeCount("my-wf")).toBe(2);
 
       // Simulate unexpected exit (not shutdown)
@@ -159,6 +165,7 @@ describe("WorkflowManager — crash recovery (Phase 3)", () => {
 
       mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
       mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
       expect(mgr.activeCount("my-wf")).toBe(2);
 
       const child = mockChildren[0];
@@ -183,6 +190,7 @@ describe("WorkflowManager — crash recovery (Phase 3)", () => {
       const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
       mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
       expect(mockChildren).toHaveLength(1);
 
       const child = mockChildren[0];
@@ -216,6 +224,7 @@ describe("WorkflowManager — crash recovery (Phase 3)", () => {
       const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
       mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
       const firstChild = mockChildren[0];
       firstChild.exitCode = 1;
       firstChild.connected = false;
@@ -260,6 +269,7 @@ describe("WorkflowManager — crash recovery (Phase 3)", () => {
 
       // Start one thread to fill the concurrency slot (so queued run stays queued on respawn)
       mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
       const firstChild = mockChildren[0];
       firstChild.exitCode = 1;
       firstChild.connected = false;
@@ -285,6 +295,7 @@ describe("WorkflowManager — crash recovery (Phase 3)", () => {
       const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
       mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
 
       const child = mockChildren[0];
       const startCall = (child.send as ReturnType<typeof vi.fn>).mock.calls[0];
@@ -322,6 +333,7 @@ describe("WorkflowManager — crash recovery (Phase 3)", () => {
 
       const launch = { prompt: "build-docker for myrepo", maxRounds: 10, dryRun: false };
       mgr.startWorkflow("my-wf", launch);
+      await vi.runAllTimersAsync();
 
       const startedCall = logStore.upsertWorkflowRun.mock.calls.find(
         (args: any[]) => (args[0] as { type: string }).type === "started",
@@ -357,6 +369,7 @@ describe("WorkflowManager — crash recovery (Phase 3)", () => {
 
       // Start one thread to fill the concurrency slot
       mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
       const firstChild = mockChildren[0];
 
       // Crash once → respawn → crash again → second respawn
@@ -398,6 +411,7 @@ describe("WorkflowManager — crash recovery (Phase 3)", () => {
       const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
       mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
       const firstChild = mockChildren[0];
       firstChild.exitCode = 1;
       firstChild.connected = false;
@@ -428,6 +442,7 @@ describe("WorkflowManager — crash recovery (Phase 3)", () => {
       const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
       mgr.startWorkflow("crash-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
 
       // Crash the worker 6 times in rapid succession (within CRASH_WINDOW_MS = 60s)
       for (let i = 0; i < 6; i++) {

packages/daemon/src/__tests__/fixtures/crash-worker.js

@@ -0,0 +1,9 @@
+// Ready then crashes on a timer; still echoes IPC so parent tests can send after respawn
+process.on("message", (msg) => {
+  if (msg && msg.type === "shutdown") {
+    process.exit(0);
+  }
+  process.send({ type: "echo", payload: msg });
+});
+process.send({ type: "ready" });
+setTimeout(() => process.exit(1), 50);

packages/daemon/src/__tests__/fixtures/echo-worker.js

@@ -0,0 +1,9 @@
+// Simple test worker: sends ready, echoes messages, handles shutdown
+process.on("message", (msg) => {
+  if (msg && msg.type === "shutdown") {
+    process.exit(0);
+  }
+  // Echo back with 'echo' type
+  process.send({ type: "echo", payload: msg });
+});
+process.send({ type: "ready" });

packages/daemon/src/__tests__/fixtures/stderr-worker.js

@@ -0,0 +1,9 @@
+// Like echo-worker but writes stderr for tail diagnostics
+console.error("stderr-marker");
+process.on("message", (msg) => {
+  if (msg && msg.type === "shutdown") {
+    process.exit(0);
+  }
+  process.send({ type: "echo", payload: msg });
+});
+process.send({ type: "ready" });

packages/daemon/src/__tests__/hot-reload.test.ts

@@ -33,6 +33,11 @@ function makeMockChild(pid = 1): MockChild {
   child.connected = true;
   child.exitCode = null;
   child.pid = pid;
+  setImmediate(() => {
+    if (child.connected) {
+      child.emit("message", { type: "ready" });
+    }
+  });
   child.send = vi.fn((msg: unknown) => {
     if (
       msg !== null &&
@@ -114,6 +119,7 @@ describe("WorkflowManager — drainAndRespawn (Phase 3 hot reload)", () => {
     const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
     mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     expect(mockChildren).toHaveLength(1);
 
     // Remove workflow from config before drain completes
@@ -134,6 +140,7 @@ describe("WorkflowManager — drainAndRespawn (Phase 3 hot reload)", () => {
 
     mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
     mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     expect(mgr.activeCount("my-wf")).toBe(2);
 
     const drainPromise = mgr.drainAndRespawn("my-wf", 5000);
@@ -165,6 +172,7 @@ describe("WorkflowManager — drainAndRespawn (Phase 3 hot reload)", () => {
     const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
     mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     expect(mockChildren).toHaveLength(1);
 
     const drainPromise = mgr.drainAndRespawn("my-wf", 5000);
@@ -181,6 +189,7 @@ describe("WorkflowManager — drainAndRespawn (Phase 3 hot reload)", () => {
     const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
     mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     expect(mockChildren).toHaveLength(1);
 
     const drainPromise = mgr.drainAndRespawn("my-wf", 5000);
@@ -198,6 +207,7 @@ describe("WorkflowManager — drainAndRespawn (Phase 3 hot reload)", () => {
     const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
     mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
 
     const drainPromise = mgr.drainAndRespawn("my-wf", 5000);
     await vi.runAllTimersAsync();
@@ -223,6 +233,7 @@ describe("WorkflowManager — drainAndRespawn (Phase 3 hot reload)", () => {
     const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
     mgr.startWorkflow("my-wf", { prompt: "first", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
 
     const drainPromise = mgr.drainAndRespawn("my-wf", 5000);
     await vi.runAllTimersAsync();
@@ -230,6 +241,7 @@ describe("WorkflowManager — drainAndRespawn (Phase 3 hot reload)", () => {
 
     // Start a new thread on the fresh worker
     mgr.startWorkflow("my-wf", { prompt: "second", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
 
     const newChild = mockChildren[1];
     const startCalls = (newChild.send as ReturnType<typeof vi.fn>).mock.calls.filter(
@@ -257,12 +269,13 @@ describe("WorkflowManager — drainWhenIdle (hot reload without interrupting in-
     vi.clearAllMocks();
   });
 
-  it("does not send shutdown while a thread is still active", () => {
+  it("does not send shutdown while a thread is still active", async () => {
     const logStore = makeLogStore();
     const config = makeWfConfig({ "my-wf": { concurrency: 1, overflow: "drop" } });
     const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
     mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     const child = mockChildren[0];
 
     mgr.drainWhenIdle("my-wf");
@@ -282,6 +295,7 @@ describe("WorkflowManager — drainWhenIdle (hot reload without interrupting in-
     const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
     mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     const child = mockChildren[0];
     const runId = (child.send as ReturnType<typeof vi.fn>).mock.calls[0][0] as { runId: string };
 
@@ -311,6 +325,7 @@ describe("WorkflowManager — drainWhenIdle (hot reload without interrupting in-
 
     mgr.startWorkflow("my-wf", { prompt: "a", maxRounds: 10, dryRun: false });
     mgr.startWorkflow("my-wf", { prompt: "b", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     const child = mockChildren[0];
     const sendMock = child.send as ReturnType<typeof vi.fn>;
     const runIdA = (sendMock.mock.calls[0][0] as { runId: string }).runId;
@@ -355,6 +370,7 @@ describe("WorkflowManager — drainWhenIdle (hot reload without interrupting in-
     const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
     mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     const child = mockChildren[0];
     const runId = (child.send as ReturnType<typeof vi.fn>).mock.calls[0][0] as { runId: string };
 
@@ -388,6 +404,7 @@ describe("WorkflowManager — drainWhenIdle (hot reload without interrupting in-
     const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
     mgr.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     const child = mockChildren[0];
     const runId = (child.send as ReturnType<typeof vi.fn>).mock.calls[0][0] as { runId: string };
 
@@ -414,6 +431,7 @@ describe("WorkflowManager — drainWhenIdle (hot reload without interrupting in-
     const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
     mgr.startWorkflow("my-wf", { prompt: "once", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     const firstChild = mockChildren[0];
     const runId = (firstChild.send as ReturnType<typeof vi.fn>).mock.calls[0][0] as {
       runId: string;
@@ -471,6 +489,7 @@ describe("Kernel — workflow hot reload via file-watcher (Phase 3)", () => {
 
     // Trigger a workflow thread so a worker is spawned
     kernel.workflowManager.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
 
     // Manually call drainAndRespawn (simulating what kernel does on workflow file change)
     const drainPromise = kernel.workflowManager.drainAndRespawn("my-wf", 1000);
@@ -511,6 +530,7 @@ describe("Kernel — workflow hot reload via file-watcher (Phase 3)", () => {
       maxRounds: 10,
       dryRun: false,
     });
+    await vi.runAllTimersAsync();
     expect(mockChildren).toHaveLength(1);
 
     // Reload config without old-wf
@@ -551,6 +571,7 @@ describe("Kernel — workflow hot reload via file-watcher (Phase 3)", () => {
     });
 
     kernel.workflowManager.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     const workersBefore = mockChildren.length;
 
     // Reload with updated concurrency — should NOT spawn a new workflow worker
@@ -573,6 +594,7 @@ describe("Kernel — workflow hot reload via file-watcher (Phase 3)", () => {
     // Can now start up to 5 concurrent threads (previously only 1)
     kernel.workflowManager.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
     kernel.workflowManager.startWorkflow("my-wf", { prompt: "test", maxRounds: 10, dryRun: false });
+    await vi.runAllTimersAsync();
     expect(kernel.workflowManager.activeCount("my-wf")).toBe(3);
 
     const stopPromise = kernel.stop();

packages/daemon/src/__tests__/kernel-phase6.test.ts

@@ -70,6 +70,14 @@ const { createKernel } = await import("../kernel.js");
 // Helpers
 // ---------------------------------------------------------------------------
 
+/** Sense worker `fork` runs on the next microtask per scheduled `start`. */
+async function flushSenseWorkerForkMicrotasks(kernel: { groups: Set<string> }): Promise<void> {
+  const n = kernel.groups.size;
+  for (let i = 0; i < n; i++) {
+    await Promise.resolve();
+  }
+}
+
 function makeConfig(overrides: Partial<NerveConfig> = {}): NerveConfig {
   return {
     senses: {
@@ -142,6 +150,8 @@ describe("kernel — getHealth", () => {
       },
     });
     const kernel = createKernel(config, nerveRoot);
+    await flushSenseWorkerForkMicrotasks(kernel);
+    await vi.runAllTimersAsync();
 
     const health = kernel.getHealth();
     expect(health.activeSenses).toBe(3);
@@ -171,6 +181,8 @@ describe("kernel — restartGroup", () => {
   it("sends shutdown to old worker and spawns new one", async () => {
     const config = makeConfig();
     const kernel = createKernel(config, nerveRoot);
+    await flushSenseWorkerForkMicrotasks(kernel);
+    await vi.runAllTimersAsync();
 
     expect(mockChildren.length).toBe(1);
     const oldChild = mockChildren[0];
@@ -178,6 +190,7 @@ describe("kernel — restartGroup", () => {
     const restartPromise = kernel.restartGroup("system");
     // The shutdown message triggers exit in the mock
     await restartPromise;
+    await vi.runAllTimersAsync();
 
     // A new child should have been spawned
     expect(mockChildren.length).toBe(2);
@@ -191,6 +204,8 @@ describe("kernel — restartGroup", () => {
   it("restartGroup on unknown group does nothing", async () => {
     const config = makeConfig();
     const kernel = createKernel(config, nerveRoot);
+    await flushSenseWorkerForkMicrotasks(kernel);
+    await vi.runAllTimersAsync();
 
     expect(mockChildren.length).toBe(1);
     await kernel.restartGroup("nonexistent");
@@ -218,6 +233,8 @@ describe("kernel — reloadConfig", () => {
   it("adds new group worker when new sense group appears", async () => {
     const config = makeConfig();
     const kernel = createKernel(config, nerveRoot);
+    await flushSenseWorkerForkMicrotasks(kernel);
+    await vi.runAllTimersAsync();
 
     expect(mockChildren.length).toBe(1); // only system group
     expect(kernel.groups.has("network")).toBe(false);
@@ -249,6 +266,9 @@ describe("kernel — reloadConfig", () => {
       api: { port: null, token: null, host: "127.0.0.1" },
     });
 
+    await Promise.resolve();
+    await vi.runAllTimersAsync();
+
     expect(kernel.groups.has("network")).toBe(true);
     expect(mockChildren.length).toBe(2); // system + network
 
@@ -283,6 +303,8 @@ describe("kernel — reloadConfig", () => {
       api: { port: null, token: null, host: "127.0.0.1" },
     };
     const kernel = createKernel(config, nerveRoot);
+    await flushSenseWorkerForkMicrotasks(kernel);
+    await vi.runAllTimersAsync();
 
     expect(mockChildren.length).toBe(2);
     expect(kernel.groups.has("network")).toBe(true);
@@ -308,6 +330,7 @@ describe("kernel — reloadConfig", () => {
     });
 
     expect(kernel.groups.has("network")).toBe(false);
+    await vi.runAllTimersAsync();
     // Network child should have received shutdown
     expect(networkChild.send).toHaveBeenCalledWith(expect.objectContaining({ type: "shutdown" }));
 
@@ -317,6 +340,8 @@ describe("kernel — reloadConfig", () => {
   it("health reflects updated sense count after reloadConfig", async () => {
     const config = makeConfig();
     const kernel = createKernel(config, nerveRoot);
+    await flushSenseWorkerForkMicrotasks(kernel);
+    await vi.runAllTimersAsync();
 
     expect(kernel.getHealth().activeSenses).toBe(1);
 

packages/daemon/src/__tests__/kernel-trigger-sense.test.ts

@@ -29,6 +29,9 @@ type MockChild = EventEmitter & {
 function makeMockChild(pid = 1): MockChild {
   const child = new EventEmitter() as MockChild;
   child.connected = true;
+  setImmediate(() => {
+    child.emit("message", { type: "ready" });
+  });
   child.send = vi.fn((msg: unknown) => {
     if (
       msg !== null &&
@@ -136,6 +139,7 @@ describe("kernel.triggerSense()", () => {
       logStore: makeMockLogStore() as never,
     });
 
+    await vi.runAllTimersAsync();
     expect(() => kernel.triggerSense("no-such-sense")).toThrow(/Unknown sense/);
 
     await kernel.stop();
@@ -169,6 +173,7 @@ describe("kernel.triggerSense()", () => {
       logStore: makeMockLogStore() as never,
     });
 
+    await vi.runAllTimersAsync();
     // Two groups → two workers
     expect(mockChildren.length).toBe(2);
 
@@ -214,6 +219,7 @@ describe("kernel.triggerSense()", () => {
       logStore: makeMockLogStore() as never,
     });
 
+    await vi.runAllTimersAsync();
     // Both senses share the "system" group → one worker only
     expect(mockChildren.length).toBe(1);
     const worker = mockChildren[0];
@@ -237,6 +243,7 @@ describe("kernel.triggerSense()", () => {
       logStore: makeMockLogStore() as never,
     });
 
+    await new Promise<void>((resolve) => setImmediate(resolve));
     const worker = mockChildren[0];
     worker.connected = false;
 

packages/daemon/src/__tests__/kernel-workflow-integration.test.ts

@@ -102,6 +102,13 @@ function makeLogStore() {
   };
 }
 
+async function flushSenseWorkerForkMicrotasks(kernel: { groups: Set<string> }): Promise<void> {
+  const n = kernel.groups.size;
+  for (let i = 0; i < n; i++) {
+    await Promise.resolve();
+  }
+}
+
 function makeConfig(overrides: Partial<NerveConfig> = {}): NerveConfig {
   return {
     senses: {
@@ -164,6 +171,8 @@ describe("kernel + workflowManager integration", () => {
         workerScript: "fake-worker.js",
         logStore,
       });
+      await flushSenseWorkerForkMicrotasks(kernel);
+      await vi.runAllTimersAsync();
 
       // Simulate a sense worker sending a signal with workflow launch payload
       // The kernel's handleWorkerMessage processes "signal" type messages
@@ -185,6 +194,8 @@ describe("kernel + workflowManager integration", () => {
         });
       }
 
+      await vi.runAllTimersAsync();
+
       // A workflow worker should be spawned and a start-thread message sent
       const workflowWorker = mockChildren.find((c) =>
         (c.send as ReturnType<typeof vi.fn>).mock.calls.some(
@@ -222,6 +233,8 @@ describe("kernel + workflowManager integration", () => {
         workerScript: "fake-worker.js",
         logStore,
       });
+      await flushSenseWorkerForkMicrotasks(kernel);
+      await vi.runAllTimersAsync();
 
       // Simulate sense worker returning a signal plus workflow launch
       const workerPool = mockChildren[0];
@@ -241,6 +254,8 @@ describe("kernel + workflowManager integration", () => {
         });
       }
 
+      await vi.runAllTimersAsync();
+
       // Find the start-thread call and verify triggerPayload
       const startThreadCall = mockChildren
         .flatMap((c) => (c.send as ReturnType<typeof vi.fn>).mock.calls as [unknown][])
@@ -275,6 +290,8 @@ describe("kernel + workflowManager integration", () => {
         workerScript: "fake-worker.js",
         logStore,
       });
+      await flushSenseWorkerForkMicrotasks(kernel);
+      await vi.runAllTimersAsync();
 
       const workerPool = mockChildren[0];
       if (workerPool) {
@@ -293,6 +310,8 @@ describe("kernel + workflowManager integration", () => {
         });
       }
 
+      await vi.runAllTimersAsync();
+
       const senseEntries = logStore.append.mock.calls
         .map((c) => c[0] as { source: string; type: string; refId: string | null })
         .filter((e) => e.source === "sense" && e.refId === "cpu-usage");
@@ -337,6 +356,8 @@ describe("kernel + workflowManager integration", () => {
         workerScript: "fake-worker.js",
         logStore,
       });
+      await flushSenseWorkerForkMicrotasks(kernel);
+      await vi.runAllTimersAsync();
 
       // Emit a regular signal (shorthand payload) — should NOT trigger any workflow
       const workerPool = mockChildren[0];
@@ -387,6 +408,8 @@ describe("kernel + workflowManager integration", () => {
         workerScript: "fake-worker.js",
         logStore,
       });
+      await flushSenseWorkerForkMicrotasks(kernel);
+      await vi.runAllTimersAsync();
 
       // Simulate sense compute returning a signal plus workflow launch
       const workerPool = mockChildren[0];
@@ -406,6 +429,8 @@ describe("kernel + workflowManager integration", () => {
         });
       }
 
+      await vi.runAllTimersAsync();
+
       expect(logStore.upsertWorkflowRun).toHaveBeenCalledWith(
         expect.objectContaining({ source: "workflow", type: "started" }),
         expect.objectContaining({ workflow: "log-test-workflow", status: "started" }),
@@ -440,6 +465,8 @@ describe("kernel + workflowManager integration", () => {
         workerScript: "fake-worker.js",
         logStore,
       });
+      await flushSenseWorkerForkMicrotasks(kernel);
+      await vi.runAllTimersAsync();
 
       // Reload with a workflow added
       const newConfig: NerveConfig = {
@@ -479,6 +506,8 @@ describe("kernel + workflowManager integration", () => {
         });
       }
 
+      await vi.runAllTimersAsync();
+
       const startThreadCall = mockChildren
         .flatMap((c) => (c.send as ReturnType<typeof vi.fn>).mock.calls as [unknown][])
         .find(
@@ -517,6 +546,8 @@ describe("kernel + workflowManager integration", () => {
         workerScript: "fake-worker.js",
         logStore,
       });
+      await flushSenseWorkerForkMicrotasks(kernel);
+      await vi.runAllTimersAsync();
 
       // Reload with the workflow removed
       const newConfig: NerveConfig = {
@@ -561,6 +592,8 @@ describe("kernel + workflowManager integration", () => {
         });
       }
 
+      await vi.runAllTimersAsync();
+
       const startThreadCall = mockChildren
         .flatMap((c) => (c.send as ReturnType<typeof vi.fn>).mock.calls as [unknown][])
         .find(
@@ -600,6 +633,8 @@ describe("kernel + workflowManager integration", () => {
         workerScript: "fake-worker.js",
         logStore,
       });
+      await flushSenseWorkerForkMicrotasks(kernel);
+      await vi.runAllTimersAsync();
 
       // Trigger a workflow via sense compute return value
       const workerPool = mockChildren[0];
@@ -619,6 +654,8 @@ describe("kernel + workflowManager integration", () => {
         });
       }
 
+      await vi.runAllTimersAsync();
+
       const stopPromise = kernel.stop();
       await vi.runAllTimersAsync();
       await expect(stopPromise).resolves.toBeUndefined();
@@ -664,6 +701,8 @@ describe("kernel + workflowManager integration", () => {
         workerScript: "fake-worker.js",
         logStore,
       });
+      await flushSenseWorkerForkMicrotasks(kernel);
+      await vi.runAllTimersAsync();
 
       const health = kernel.getHealth();
       expect(health).toHaveProperty("activeWorkflows");

packages/daemon/src/__tests__/kernel.test.ts

@@ -16,10 +16,12 @@ type MockChild = EventEmitter & {
   send: ReturnType<typeof vi.fn>;
   kill: ReturnType<typeof vi.fn>;
   pid: number;
+  connected: boolean;
 };
 
 function makeMockChild(pid = 1): MockChild {
   const child = new EventEmitter() as MockChild;
+  child.connected = true;
   setImmediate(() => {
     child.emit("message", { type: "ready" });
   });
@@ -27,7 +29,10 @@ function makeMockChild(pid = 1): MockChild {
     if (msg === null || typeof msg !== "object") return;
     const m = msg as Record<string, unknown>;
     if (m.type === "shutdown") {
-      setImmediate(() => child.emit("exit", 0, null));
+      setImmediate(() => {
+        child.connected = false;
+        child.emit("exit", 0, null);
+      });
       return;
     }
     if (m.type === "compute" && typeof m.sense === "string") {
@@ -37,6 +42,7 @@ function makeMockChild(pid = 1): MockChild {
     }
   });
   child.kill = vi.fn((_signal?: string) => {
+    child.connected = false;
     child.emit("exit", null, _signal ?? "SIGKILL");
   });
   child.pid = pid;
@@ -59,6 +65,14 @@ const { createLogStore } = await import("@uncaged/nerve-store");
 // Helpers
 // ---------------------------------------------------------------------------
 
+/** `WorkerRuntime.start` schedules `fork` on the next microtask — flush one tick per initial group. */
+async function flushSenseWorkerForkMicrotasks(kernel: { groups: Set<string> }): Promise<void> {
+  const n = kernel.groups.size;
+  for (let i = 0; i < n; i++) {
+    await Promise.resolve();
+  }
+}
+
 function makeConfig(overrides: Partial<NerveConfig> = {}): NerveConfig {
   return {
     senses: {
@@ -173,6 +187,7 @@ describe("kernel — message routing", () => {
       },
     });
     const kernel = createKernel(config, nerveRoot);
+    await flushSenseWorkerForkMicrotasks(kernel);
 
     const child = mockChildren[0];
     child.emit("message", { type: "error", sense: "cpu-usage", error: "compute failed" });
@@ -201,6 +216,7 @@ describe("kernel — message routing", () => {
       },
     });
     const kernel = createKernel(config, nerveRoot);
+    await flushSenseWorkerForkMicrotasks(kernel);
 
     const child = mockChildren[0];
     const callsBefore = stderrSpy.mock.calls.length;
@@ -228,6 +244,7 @@ describe("kernel — message routing", () => {
       },
     });
     const kernel = createKernel(config, nerveRoot);
+    await flushSenseWorkerForkMicrotasks(kernel);
 
     const child = mockChildren[0];
     expect(() => child.emit("message", { type: "unknown-type" })).not.toThrow();
@@ -290,6 +307,7 @@ describe("kernel — groupForSense mapping", () => {
       api: { port: null, token: null, host: "127.0.0.1" },
     };
     const kernel = createKernel(config, nerveRoot);
+    await flushSenseWorkerForkMicrotasks(kernel);
 
     // system and network = 2 unique groups
     expect(mockChildren.length).toBe(2);
@@ -311,8 +329,10 @@ describe("kernel — groupForSense mapping", () => {
       },
     });
     const kernel = createKernel(config, nerveRoot);
-
+    await flushSenseWorkerForkMicrotasks(kernel);
     const child = mockChildren[0];
+    child.emit("message", { type: "ready" });
+
     vi.advanceTimersByTime(500);
 
     expect(child.send).toHaveBeenCalledWith(

packages/daemon/src/__tests__/worker-pool.test.ts

@@ -50,6 +50,7 @@ async function startWorkerWithReady(
   group: string,
 ): Promise<void> {
   const pr = pool.startWorker(group);
+  await Promise.resolve();
   const child = mockChildren[mockChildren.length - 1];
   child.emit("message", { type: "ready" });
   await pr;
@@ -137,6 +138,7 @@ describe("createSenseWorkerPool", () => {
     expect(pool.activeGroupCount()).toBe(1);
     pool.evictGroup("x");
     expect(pool.hasWorkerForGroup("x")).toBe(false);
+    await Promise.resolve();
     expect(mockChildren[0].send).toHaveBeenCalledWith(
       expect.objectContaining({ type: "shutdown" }),
     );
@@ -159,6 +161,7 @@ describe("createSenseWorkerPool", () => {
 
     const p = pool.restartGroup("g");
     expect(onBeforeGroupRestart).toHaveBeenCalledWith("g");
+    await Promise.resolve();
     expect(mockChildren[0].send).toHaveBeenCalledWith(
       expect.objectContaining({ type: "shutdown" }),
     );
@@ -171,7 +174,7 @@ describe("createSenseWorkerPool", () => {
   });
 
   it("onWorkerCrashed runs and schedules respawn after non-zero exit", async () => {
-    vi.useFakeTimers({ shouldAdvanceTime: true });
+    vi.useFakeTimers();
     const onWorkerCrashed = vi.fn();
     const pool = createSenseWorkerPool({
       nerveRoot: "/tmp/n",

packages/daemon/src/__tests__/worker-runtime.test.ts

@@ -0,0 +1,181 @@
+import { dirname, join } from "node:path";
+import { fileURLToPath } from "node:url";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { createWorkerRuntime } from "../worker-runtime.js";
+
+const fixturesDir = join(dirname(fileURLToPath(import.meta.url)), "fixtures");
+const echoWorkerPath = join(fixturesDir, "echo-worker.js");
+const crashWorkerPath = join(fixturesDir, "crash-worker.js");
+const stderrWorkerPath = join(fixturesDir, "stderr-worker.js");
+
+function baseConfig(script: string) {
+  return {
+    script,
+    argsForKey: () => [],
+    forwardStderr: true,
+    onMessage: vi.fn(),
+    onReady: vi.fn(),
+    onExit: vi.fn(),
+    onCrashLimitReached: null,
+    respawn: {
+      enabled: true,
+      maxCrashes: 6,
+      windowMs: 60_000,
+      delayMs: 80,
+      allowRespawn: null,
+    },
+    shutdownTimeoutMs: 5000,
+  };
+}
+
+describe("createWorkerRuntime", () => {
+  const runtimes: Array<{ shutdown: () => Promise<void> }> = [];
+
+  afterEach(async () => {
+    await Promise.all(runtimes.splice(0).map((r) => r.shutdown()));
+  });
+
+  function track<R extends { shutdown: () => Promise<void> }>(r: R): R {
+    runtimes.push(r);
+    return r;
+  }
+
+  it("start + send message + receive echo", async () => {
+    const incoming: unknown[] = [];
+    const rt = track(
+      createWorkerRuntime({
+        ...baseConfig(echoWorkerPath),
+        onMessage: (_key, msg) => {
+          incoming.push(msg);
+        },
+      }),
+    );
+
+    await rt.start("a");
+    expect(rt.has("a")).toBe(true);
+    await rt.send("a", { type: "ping", n: 1 });
+
+    await vi.waitFor(() => {
+      expect(incoming.some((m) => isEchoOf(m, { type: "ping", n: 1 }))).toBe(true);
+    });
+    await rt.shutdown();
+  });
+
+  it("cold start on send (no explicit start)", async () => {
+    const incoming: unknown[] = [];
+    const rt = track(
+      createWorkerRuntime({
+        ...baseConfig(echoWorkerPath),
+        onMessage: (_key, msg) => {
+          incoming.push(msg);
+        },
+      }),
+    );
+
+    expect(rt.has("x")).toBe(false);
+    await rt.send("x", { type: "hi" });
+    await vi.waitFor(() => {
+      expect(rt.has("x")).toBe(true);
+      expect(incoming.some((m) => isEchoOf(m, { type: "hi" }))).toBe(true);
+    });
+    await rt.shutdown();
+  });
+
+  it("evict stops worker; has() is false", async () => {
+    const rt = track(createWorkerRuntime(baseConfig(echoWorkerPath)));
+    await rt.start("k");
+    expect(rt.has("k")).toBe(true);
+    await rt.evict("k", null);
+    expect(rt.has("k")).toBe(false);
+    await rt.shutdown();
+  });
+
+  it("drain stops and respawns (new pid)", async () => {
+    const rt = track(createWorkerRuntime(baseConfig(echoWorkerPath)));
+    await rt.start("k");
+    const before = rt.pid("k");
+    expect(before).not.toBeNull();
+    await rt.drain("k", null);
+    const after = rt.pid("k");
+    expect(after).not.toBeNull();
+    expect(after).not.toBe(before);
+    await rt.shutdown();
+  });
+
+  it("crash triggers auto-respawn", async () => {
+    const incoming: unknown[] = [];
+    const onExit = vi.fn();
+    const rt = track(
+      createWorkerRuntime({
+        ...baseConfig(crashWorkerPath),
+        onExit,
+        onMessage: (_key, msg) => {
+          incoming.push(msg);
+        },
+      }),
+    );
+
+    await rt.start("c");
+
+    await vi.waitFor(() => expect(onExit.mock.calls.length).toBeGreaterThanOrEqual(1), {
+      timeout: 3000,
+    });
+    await vi.waitFor(() => expect(rt.has("c")).toBe(true), { timeout: 3000 });
+
+    await rt.send("c", { type: "after-crash" });
+    await vi.waitFor(() => {
+      expect(incoming.some((m) => isEchoOf(m, { type: "after-crash" }))).toBe(true);
+    });
+    await rt.shutdown();
+  });
+
+  it("crash limit reached → no more automatic respawns", async () => {
+    const rt = track(
+      createWorkerRuntime({
+        ...baseConfig(crashWorkerPath),
+        respawn: {
+          enabled: true,
+          maxCrashes: 2,
+          windowMs: 60_000,
+          delayMs: 50,
+          allowRespawn: null,
+        },
+      }),
+    );
+
+    await rt.start("z");
+
+    await vi.waitFor(() => expect(rt.has("z")).toBe(false), { timeout: 8000 });
+
+    await rt.shutdown();
+  });
+
+  it("shutdown stops all workers", async () => {
+    const rt = track(createWorkerRuntime(baseConfig(echoWorkerPath)));
+    await rt.start("a");
+    await rt.start("b");
+    expect(rt.keys().sort()).toEqual(["a", "b"].sort());
+    await rt.shutdown();
+    expect(rt.keys()).toEqual([]);
+    expect(rt.has("a")).toBe(false);
+    expect(rt.has("b")).toBe(false);
+  });
+
+  it("stderrTail captures stderr output", async () => {
+    const rt = track(createWorkerRuntime(baseConfig(stderrWorkerPath)));
+    await rt.start("s");
+    await vi.waitFor(() => {
+      expect(rt.stderrTail("s")).toContain("stderr-marker");
+    });
+    await rt.shutdown();
+  });
+});
+
+function isEchoOf(msg: unknown, payload: unknown): boolean {
+  return (
+    typeof msg === "object" &&
+    msg !== null &&
+    (msg as Record<string, unknown>).type === "echo" &&
+    JSON.stringify((msg as Record<string, unknown>).payload) === JSON.stringify(payload)
+  );
+}

packages/daemon/src/__tests__/workflow-manager.test.ts

@@ -26,6 +26,11 @@ function makeMockChild(pid = 1): MockChild {
   child.connected = true;
   child.exitCode = null;
   child.pid = pid;
+  setImmediate(() => {
+    if (child.connected) {
+      child.emit("message", { type: "ready" });
+    }
+  });
   child.send = vi.fn((msg: unknown) => {
     if (
       msg !== null &&
@@ -110,7 +115,7 @@ describe("WorkflowManager", () => {
   });
 
   describe("startWorkflow under concurrency limit dispatches thread", () => {
-    it("forks a worker and sends start-thread when active < concurrency", () => {
+    it("forks a worker and sends start-thread when active < concurrency", async () => {
       const logStore = makeLogStore();
       const config = makeConfig({
         "my-workflow": { concurrency: 2, overflow: "drop" },
@@ -118,6 +123,7 @@ describe("WorkflowManager", () => {
       const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
       mgr.startWorkflow("my-workflow", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
 
       expect(mockChildren).toHaveLength(1);
       expect(mockChildren[0].send).toHaveBeenCalledWith(
@@ -126,7 +132,7 @@ describe("WorkflowManager", () => {
       expect(mgr.activeCount("my-workflow")).toBe(1);
     });
 
-    it("reuses the same worker for a second thread under the limit", () => {
+    it("reuses the same worker for a second thread under the limit", async () => {
       const logStore = makeLogStore();
       const config = makeConfig({
         "my-workflow": { concurrency: 3, overflow: "drop" },
@@ -135,6 +141,7 @@ describe("WorkflowManager", () => {
 
       mgr.startWorkflow("my-workflow", { prompt: "test 1", maxRounds: 10, dryRun: false });
       mgr.startWorkflow("my-workflow", { prompt: "test 2", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
 
       // Only one forked child — worker is reused
       expect(mockChildren).toHaveLength(1);
@@ -142,7 +149,7 @@ describe("WorkflowManager", () => {
       expect(mgr.activeCount("my-workflow")).toBe(2);
     });
 
-    it("logs a 'started' event for each dispatched thread", () => {
+    it("logs a 'started' event for each dispatched thread", async () => {
       const logStore = makeLogStore();
       const config = makeConfig({
         "my-workflow": { concurrency: 2, overflow: "drop" },
@@ -150,6 +157,7 @@ describe("WorkflowManager", () => {
       const mgr = createWorkflowManager("/nerve-root", config, logStore);
 
       mgr.startWorkflow("my-workflow", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
 
       expect(logStore.upsertWorkflowRun).toHaveBeenCalledWith(
         expect.objectContaining({ source: "workflow", type: "started" }),
@@ -159,7 +167,7 @@ describe("WorkflowManager", () => {
   });
 
   describe("startWorkflow at limit with drop overflow drops the request", () => {
-    it("does NOT send start-thread when at concurrency limit with overflow=drop", () => {
+    it("does NOT send start-thread when at concurrency limit with overflow=drop", async () => {
       const logStore = makeLogStore();
       const config = makeConfig({
         "drop-wf": { concurrency: 1, overflow: "drop" },
@@ -169,6 +177,7 @@ describe("WorkflowManager", () => {
       mgr.startWorkflow("drop-wf", { prompt: "first", maxRounds: 10, dryRun: false });
       // now at limit — second call should be dropped
       mgr.startWorkflow("drop-wf", { prompt: "second", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
 
       expect(mgr.activeCount("drop-wf")).toBe(1);
       expect(mgr.queueLength("drop-wf")).toBe(0);
@@ -254,7 +263,7 @@ describe("WorkflowManager", () => {
   });
 
   describe("completing a thread dequeues the next one", () => {
-    it("dispatches the next queued thread when the active thread sends completed", () => {
+    it("dispatches the next queued thread when the active thread sends completed", async () => {
       const logStore = makeLogStore();
       const config = makeConfig({
         "queue-wf": { concurrency: 1, overflow: "queue", maxQueue: 5 },
@@ -263,6 +272,7 @@ describe("WorkflowManager", () => {
 
       mgr.startWorkflow("queue-wf", { prompt: "first", maxRounds: 10, dryRun: false });
       mgr.startWorkflow("queue-wf", { prompt: "second", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
 
       expect(mgr.activeCount("queue-wf")).toBe(1);
       expect(mgr.queueLength("queue-wf")).toBe(1);
@@ -289,7 +299,7 @@ describe("WorkflowManager", () => {
       );
     });
 
-    it("dispatches next queued thread when active thread sends failed", () => {
+    it("dispatches next queued thread when active thread sends failed", async () => {
       const logStore = makeLogStore();
       const config = makeConfig({
         "queue-wf": { concurrency: 1, overflow: "queue", maxQueue: 5 },
@@ -298,6 +308,7 @@ describe("WorkflowManager", () => {
 
       mgr.startWorkflow("queue-wf", { prompt: "first", maxRounds: 10, dryRun: false });
       mgr.startWorkflow("queue-wf", { prompt: "second", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
 
       const child = mockChildren[0];
       const firstRunId = (child.send as ReturnType<typeof vi.fn>).mock.calls[0][0].runId as string;
@@ -325,6 +336,7 @@ describe("WorkflowManager", () => {
 
       mgr.startWorkflow("wf-a", { prompt: "test", maxRounds: 10, dryRun: false });
       mgr.startWorkflow("wf-b", { prompt: "test", maxRounds: 10, dryRun: false });
+      await vi.runAllTimersAsync();
 
       // Two distinct workers should have been forked
       expect(mockChildren).toHaveLength(2);

packages/daemon/src/worker-pool.ts

@@ -1,19 +1,13 @@
 /**
- * Sense worker pool — forked child processes per sense group (IPC lifecycle).
+ * Sense worker pool — thin wrapper around WorkerRuntime (RFC-006): one fork per sense group.
  */
 
-import { fork } from "node:child_process";
-import type { ChildProcess } from "node:child_process";
 import { dirname, join } from "node:path";
 import { fileURLToPath } from "node:url";
 
-import type { ComputeMessage, ShutdownMessage } from "./ipc.js";
-import { parseWorkerMessage } from "./ipc.js";
-import {
-  formatCapturedStderrTail,
-  formatChildExitSummary,
-  teeCapturedStderr,
-} from "./worker-fork-support.js";
+import type { ComputeMessage } from "./ipc.js";
+import { formatCapturedStderrTail, formatChildExitSummary } from "./worker-fork-support.js";
+import { createWorkerRuntime } from "./worker-runtime.js";
 
 export function resolveWorkerScript(): string {
   const __filename = fileURLToPath(import.meta.url);
@@ -21,17 +15,12 @@ export function resolveWorkerScript(): string {
   return join(__dir, "sense-worker.js");
 }
 
-type WorkerEntry = {
-  group: string;
-  process: ChildProcess;
-};
-
 export type SenseWorkerPoolOptions = {
   nerveRoot: string;
   workerScript: string;
   /** Invoked for every IPC message from a worker (including ready / signal / error). */
   onWorkerMessage: (raw: unknown) => void;
-  /** Sense names in a group — used when clearing scheduler state on crash or restart. */
+  /** Sense names in a group — reserved for scheduler-aligned cleanup (kernel passes current config). */
   sensesForGroup: (group: string) => string[];
   /**
    * Called when a worker exits with non-zero code before scheduling a respawn
@@ -58,144 +47,107 @@ export type SenseWorkerPool = {
   activeGroupCount: () => number;
 };
 
-function spawnWorker(
-  nerveRoot: string,
-  group: string,
-  workerScript: string,
-  stderrTail: { value: string },
-): ChildProcess {
-  const child = fork(workerScript, ["--group", group, "--root", nerveRoot], {
-    stdio: ["ignore", "inherit", "pipe", "ipc"],
-  });
-  teeCapturedStderr(child, stderrTail);
-  child.on("error", (err) => {
-    if ((err as NodeJS.ErrnoException).code !== "EPIPE") {
-      console.error("[worker] error:", err.message);
-    }
-  });
-  return child;
-}
-
-function sendComputeToProcess(worker: ChildProcess, senseName: string): void {
-  if (worker.connected === false) return;
-  const msg: ComputeMessage = { type: "compute", sense: senseName };
-  try {
-    worker.send(msg);
-  } catch {
-    // IPC channel closed between connected check and send
-  }
-}
-
-function sendShutdownToProcess(worker: ChildProcess): void {
-  if (worker.connected === false) return;
-  const msg: ShutdownMessage = { type: "shutdown" };
-  try {
-    worker.send(msg);
-  } catch {
-    // IPC channel closed between connected check and send
-  }
-}
-
-function waitForExit(child: ChildProcess, timeoutMs: number): Promise<void> {
-  return new Promise((resolve) => {
-    const timer = setTimeout(() => {
-      child.kill("SIGKILL");
-      resolve();
-    }, timeoutMs);
-    child.once("exit", () => {
-      clearTimeout(timer);
-      resolve();
-    });
-  });
-}
+/** Matches legacy pool: long crash window, 1s respawn delay, practical unlimited respawns. */
+const SENSE_WORKER_RESPAWN = {
+  enabled: true,
+  maxCrashes: 100_000,
+  windowMs: 86_400_000,
+  delayMs: 1000,
+} as const;
 
 export function createSenseWorkerPool(options: SenseWorkerPoolOptions): SenseWorkerPool {
-  const workers = new Map<string, WorkerEntry>();
-
-  function startWorker(group: string): Promise<void> {
-    const stderrTail = { value: "" };
-    const child = spawnWorker(options.nerveRoot, group, options.workerScript, stderrTail);
-
-    let workerReadyResolve: (() => void) | undefined;
-    const workerReady = new Promise<void>((resolve) => {
-      workerReadyResolve = resolve;
-    });
-
-    child.on("message", (raw: unknown) => {
-      const result = parseWorkerMessage(raw);
-      if (result.ok && result.value.type === "ready") {
-        workerReadyResolve?.();
-      }
+  const runtime = createWorkerRuntime<string>({
+    script: options.workerScript,
+    argsForKey: (group) => ["--group", group, "--root", options.nerveRoot],
+    forwardStderr: true,
+    onMessage: (_key, raw) => {
       options.onWorkerMessage(raw);
-    });
-
-    child.on("exit", (code, signal) => {
-      const summary = formatChildExitSummary(code, signal ?? null);
+    },
+    onReady: (_key, msg) => {
+      options.onWorkerMessage(msg);
+    },
+    onCrashLimitReached: null,
+    onExit: (group, code, signal) => {
+      const sig =
+        signal === null || signal === undefined || signal === ""
+          ? null
+          : (signal as NodeJS.Signals);
+      const summary = formatChildExitSummary(code, sig);
       process.stderr.write(
-        `[kernel] worker for group "${group}" exited (${summary})${formatCapturedStderrTail(stderrTail.value)}\n`,
+        `[kernel] worker for group "${group}" exited (${summary})${formatCapturedStderrTail(runtime.stderrTail(group))}\n`,
       );
-      workerReadyResolve?.();
       if (!options.isStopped() && code !== 0) {
         process.stderr.write(`[kernel] respawning worker for group "${group}" in 1s\n`);
         options.onWorkerCrashed(group);
-        setTimeout(() => {
-          if (!options.isStopped()) {
-            startWorker(group);
-          }
-        }, 1000);
       }
-    });
+    },
+    respawn: {
+      ...SENSE_WORKER_RESPAWN,
+      allowRespawn: (_group) => !options.isStopped(),
+    },
+    shutdownTimeoutMs: 5000,
+  });
 
-    workers.set(group, { group, process: child });
-    return workerReady;
+  /** Groups we have ever started — mirrors legacy Map presence for `restartGroup` no-op when unknown. */
+  const trackedGroups = new Set<string>();
+  /** Marks groups mid-evict so `hasWorkerForGroup` drops immediately (legacy synchronous eviction). */
+  const evicting = new Set<string>();
+
+  async function startWorker(group: string): Promise<void> {
+    trackedGroups.add(group);
+    await runtime.start(group);
   }
 
   async function restartGroup(group: string): Promise<void> {
-    const entry = workers.get(group);
-    if (entry === undefined) return;
-
-    options.onBeforeGroupRestart(group);
-
-    sendShutdownToProcess(entry.process);
-    await waitForExit(entry.process, 5000);
-
-    if (!options.isStopped()) {
-      await startWorker(group);
+    if (!trackedGroups.has(group)) {
+      return;
     }
+    options.onBeforeGroupRestart(group);
+    await runtime.drain(group, null);
   }
 
   function evictGroup(group: string): void {
-    const entry = workers.get(group);
-    if (entry === undefined) return;
-    sendShutdownToProcess(entry.process);
-    workers.delete(group);
+    trackedGroups.delete(group);
+    evicting.add(group);
+    void runtime.evict(group, null).finally(() => {
+      evicting.delete(group);
+    });
   }
 
   async function shutdownAll(): Promise<void> {
-    const exitPromises: Promise<void>[] = [];
-    for (const entry of workers.values()) {
-      sendShutdownToProcess(entry.process);
-      exitPromises.push(waitForExit(entry.process, 5000));
-    }
-    await Promise.all(exitPromises);
+    await runtime.shutdown();
+    trackedGroups.clear();
+    evicting.clear();
   }
 
   function sendCompute(group: string, senseName: string): void {
-    const entry = workers.get(group);
-    if (entry === undefined) return;
-    sendComputeToProcess(entry.process, senseName);
+    if (!trackedGroups.has(group) || evicting.has(group)) {
+      return;
+    }
+    // Legacy pool: `child.send` no-op when IPC is closed (still allow cold start: child === null).
+    if (runtime.hasDisconnectedChild(group)) {
+      return;
+    }
+    const msg: ComputeMessage = { type: "compute", sense: senseName };
+    if (!runtime.trySendSync(group, msg)) {
+      void runtime.send(group, msg).catch(() => {
+        // IPC channel may close between scheduling and send — same as legacy try/catch on child.send
+      });
+    }
   }
 
   function getWorkerPid(group: string): number | null {
-    return workers.get(group)?.process.pid ?? null;
+    return runtime.pid(group);
   }
 
+  /** True once `startWorker` has been called for the group and it is not mid-evict (matches legacy Map key). */
   function hasWorkerForGroup(group: string): boolean {
-    return workers.has(group);
+    return trackedGroups.has(group) && !evicting.has(group);
   }
 
+  /** Count of sense groups with a worker slot (includes not-yet-ready), excluding evicted keys. */
   function activeGroupCount(): number {
-    return workers.size;
+    return trackedGroups.size;
   }
 
   return {

packages/daemon/src/worker-runtime.ts

@@ -0,0 +1,422 @@
+/**
+ * Generic message-routed worker process manager (RFC-006).
+ * One forked Node child per key; cold start, crash respawn, drain/evict, shutdown.
+ */
+
+import { type ChildProcess, type Serializable, fork } from "node:child_process";
+import { isPlainRecord } from "@uncaged/nerve-core";
+
+const STDERR_TAIL_MAX_CHARS = 2048;
+
+export type WorkerDrainOpts = {
+  shutdownTimeoutMs: number | null;
+};
+
+export type WorkerRuntimeConfig<K extends string> = {
+  script: string;
+  argsForKey: (key: K) => string[];
+  /** When false, stderr is not captured into `stderrTail` (e.g. tests without a pipe). */
+  forwardStderr: boolean;
+  onMessage: (key: K, msg: unknown) => void;
+  onReady: (key: K, msg: unknown) => void;
+  onExit: (key: K, code: number | null, signal: string | null) => void;
+  /** Invoked when automatic respawn is skipped because `maxCrashes` was exceeded in `windowMs`. */
+  onCrashLimitReached: ((key: K) => void) | null;
+  respawn: {
+    enabled: boolean;
+    maxCrashes: number;
+    windowMs: number;
+    delayMs: number;
+    /** When non-null, return false to skip automatic respawn after an unexpected exit. */
+    allowRespawn: ((key: K) => boolean) | null;
+  };
+  shutdownTimeoutMs: number;
+};
+
+export type WorkerRuntime<K extends string> = {
+  send: (key: K, msg: unknown) => Promise<void>;
+  /** When the worker is already ready and IPC-connected, sends synchronously (returns true). Otherwise false — caller may fall back to `send`. */
+  trySendSync: (key: K, msg: unknown) => boolean;
+  start: (key: K) => Promise<void>;
+  evict: (key: K, opts: WorkerDrainOpts | null) => Promise<void>;
+  drain: (key: K, opts: WorkerDrainOpts | null) => Promise<void>;
+  shutdown: () => Promise<void>;
+  has: (key: K) => boolean;
+  /** True when a child exists but IPC is disconnected (legacy pool skipped sends in this case). */
+  hasDisconnectedChild: (key: K) => boolean;
+  pid: (key: K) => number | null;
+  keys: () => K[];
+  stderrTail: (key: K) => string;
+};
+
+type WorkerMachineState = "stopped" | "starting" | "ready" | "draining";
+
+type ReadyWaiter = {
+  resolve: () => void;
+  reject: (err: Error) => void;
+};
+
+/** Internal: one forked process slot (ManagedWorker). */
+type WorkerSlot<K extends string> = {
+  key: K;
+  state: WorkerMachineState;
+  child: ChildProcess | null;
+  pid: number | null;
+  stderrTail: string;
+  crashTimestamps: number[];
+  expectExit: boolean;
+  readyWaiters: ReadyWaiter[];
+  opChain: Promise<void>;
+};
+
+function isReadyIpcMessage(raw: unknown): boolean {
+  return isPlainRecord(raw) && raw.type === "ready";
+}
+
+function signalToString(signal: NodeJS.Signals | null): string | null {
+  if (signal === null) {
+    return null;
+  }
+  return String(signal);
+}
+
+function attachStderrTail<K extends string>(child: ChildProcess, slot: WorkerSlot<K>): void {
+  const stream = child.stderr;
+  if (stream == null) {
+    return;
+  }
+  stream.setEncoding("utf8");
+  stream.on("data", (chunk: string | Buffer) => {
+    const text = typeof chunk === "string" ? chunk : chunk.toString("utf8");
+    slot.stderrTail = (slot.stderrTail + text).slice(-STDERR_TAIL_MAX_CHARS);
+  });
+}
+
+function enqueueOp<K extends string>(slot: WorkerSlot<K>, fn: () => Promise<void>): Promise<void> {
+  const run = slot.opChain.then(fn, fn);
+  slot.opChain = run.then(
+    () => {},
+    () => {},
+  );
+  return run;
+}
+
+function resolveReadyWaiters<K extends string>(slot: WorkerSlot<K>): void {
+  const waiters = slot.readyWaiters;
+  slot.readyWaiters = [];
+  for (const w of waiters) {
+    w.resolve();
+  }
+}
+
+function rejectReadyWaiters<K extends string>(slot: WorkerSlot<K>, err: Error): void {
+  const waiters = slot.readyWaiters;
+  slot.readyWaiters = [];
+  for (const w of waiters) {
+    w.reject(err);
+  }
+}
+
+function waitForReady<K extends string>(
+  slot: WorkerSlot<K>,
+  shutdownTimeoutMs: number,
+): Promise<void> {
+  if (slot.state === "ready" && slot.child !== null && slot.child.connected) {
+    return Promise.resolve();
+  }
+  return new Promise((resolve, reject) => {
+    let settled = false;
+    const timer = setTimeout(() => {
+      if (!settled) {
+        settled = true;
+        reject(new Error(`Worker "${String(slot.key)}" ready timeout`));
+      }
+    }, shutdownTimeoutMs);
+    slot.readyWaiters.push({
+      resolve: () => {
+        if (settled) {
+          return;
+        }
+        settled = true;
+        clearTimeout(timer);
+        resolve();
+      },
+      reject: (err: Error) => {
+        if (settled) {
+          return;
+        }
+        settled = true;
+        clearTimeout(timer);
+        reject(err);
+      },
+    });
+  });
+}
+
+async function waitForChildExit(child: ChildProcess, timeoutMs: number): Promise<void> {
+  await new Promise<void>((resolve) => {
+    const timer = setTimeout(() => {
+      child.kill("SIGKILL");
+    }, timeoutMs);
+    child.once("exit", () => {
+      clearTimeout(timer);
+      resolve();
+    });
+  });
+}
+
+export function createWorkerRuntime<K extends string>(
+  config: WorkerRuntimeConfig<K>,
+): WorkerRuntime<K> {
+  const workers = new Map<K, WorkerSlot<K>>();
+
+  function getOrCreateSlot(key: K): WorkerSlot<K> {
+    let slot = workers.get(key);
+    if (slot === undefined) {
+      slot = {
+        key,
+        state: "stopped",
+        child: null,
+        pid: null,
+        stderrTail: "",
+        crashTimestamps: [],
+        expectExit: false,
+        readyWaiters: [],
+        opChain: Promise.resolve(),
+      };
+      workers.set(key, slot);
+    }
+    return slot;
+  }
+
+  function handleWorkerMessage(slot: WorkerSlot<K>, msg: unknown): void {
+    if (isReadyIpcMessage(msg)) {
+      if (slot.state === "starting") {
+        slot.state = "ready";
+        config.onReady(slot.key, msg);
+        resolveReadyWaiters(slot);
+      }
+      return;
+    }
+    config.onMessage(slot.key, msg);
+  }
+
+  function onChildExit(
+    slot: WorkerSlot<K>,
+    code: number | null,
+    signal: NodeJS.Signals | null,
+  ): void {
+    config.onExit(slot.key, code, signalToString(signal));
+
+    if (slot.child !== null) {
+      slot.child.removeAllListeners("message");
+      slot.child.removeAllListeners("exit");
+    }
+
+    const wasExpect = slot.expectExit;
+    slot.expectExit = false;
+
+    slot.child = null;
+    slot.pid = null;
+
+    if (wasExpect) {
+      slot.state = "stopped";
+      return;
+    }
+
+    rejectReadyWaiters(slot, new Error(`Worker "${String(slot.key)}" exited unexpectedly`));
+    slot.state = "stopped";
+
+    void enqueueOp(slot, async () => {
+      await handleUnexpectedCrashRecovery(slot);
+    });
+  }
+
+  function registerChild(slot: WorkerSlot<K>, child: ChildProcess): void {
+    slot.child = child;
+    slot.pid = child.pid ?? null;
+    if (config.forwardStderr) {
+      attachStderrTail(child, slot);
+    }
+    child.on("message", (msg: unknown) => {
+      handleWorkerMessage(slot, msg);
+    });
+    child.on("exit", (code, sig) => {
+      onChildExit(slot, code, sig ?? null);
+    });
+  }
+
+  async function forkAndWaitReady(slot: WorkerSlot<K>): Promise<void> {
+    if (slot.state === "ready" && slot.child !== null && slot.child.connected) {
+      return;
+    }
+
+    slot.state = "starting";
+
+    let child: ChildProcess;
+    try {
+      child = fork(config.script, config.argsForKey(slot.key), {
+        stdio: ["ignore", "inherit", "pipe", "ipc"],
+        env: process.env,
+      });
+    } catch (e) {
+      slot.state = "stopped";
+      const err = e instanceof Error ? e : new Error(String(e));
+      rejectReadyWaiters(slot, err);
+      throw err;
+    }
+
+    registerChild(slot, child);
+    await waitForReady(slot, config.shutdownTimeoutMs);
+  }
+
+  function resolveShutdownTimeoutMs(opts: WorkerDrainOpts | null): number {
+    if (opts !== null && opts.shutdownTimeoutMs !== null) {
+      return opts.shutdownTimeoutMs;
+    }
+    return config.shutdownTimeoutMs;
+  }
+
+  async function gracefulStop(slot: WorkerSlot<K>, shutdownTimeoutMs: number): Promise<void> {
+    if (slot.child === null) {
+      return;
+    }
+    slot.expectExit = true;
+    slot.state = "draining";
+    const child = slot.child;
+    try {
+      child.send({ type: "shutdown" });
+    } catch {
+      // IPC channel may have closed between null-check and send
+    }
+    await waitForChildExit(child, shutdownTimeoutMs);
+  }
+
+  async function handleUnexpectedCrashRecovery(slot: WorkerSlot<K>): Promise<void> {
+    if (!config.respawn.enabled) {
+      return;
+    }
+    if (config.respawn.allowRespawn !== null && !config.respawn.allowRespawn(slot.key)) {
+      return;
+    }
+
+    const now = Date.now();
+    slot.crashTimestamps.push(now);
+    slot.crashTimestamps = slot.crashTimestamps.filter((t) => now - t <= config.respawn.windowMs);
+
+    if (slot.crashTimestamps.length >= config.respawn.maxCrashes) {
+      console.error(
+        `[WorkerRuntime] worker "${String(slot.key)}" exceeded crash limit (${String(config.respawn.maxCrashes)} in ${String(config.respawn.windowMs)}ms); not respawning`,
+      );
+      if (config.onCrashLimitReached !== null) {
+        config.onCrashLimitReached(slot.key);
+      }
+      return;
+    }
+
+    await new Promise<void>((resolve) => setTimeout(resolve, config.respawn.delayMs));
+    await forkAndWaitReady(slot);
+  }
+
+  async function shutdownWorker(slot: WorkerSlot<K>): Promise<void> {
+    await gracefulStop(slot, config.shutdownTimeoutMs);
+    workers.delete(slot.key);
+  }
+
+  function isActive(slot: WorkerSlot<K>): boolean {
+    return slot.state === "ready" && slot.child !== null && slot.child.connected;
+  }
+
+  return {
+    send: async (key: K, msg: unknown) => {
+      const slot = getOrCreateSlot(key);
+      await enqueueOp(slot, async () => {
+        await forkAndWaitReady(slot);
+        const child = slot.child;
+        if (child === null || !child.connected) {
+          throw new Error(`Worker "${String(key)}" is not connected`);
+        }
+        child.send(msg as Serializable);
+      });
+    },
+
+    trySendSync: (key: K, msg: unknown): boolean => {
+      const slot = workers.get(key);
+      if (slot === undefined || !isActive(slot)) {
+        return false;
+      }
+      const child = slot.child;
+      if (child === null || !child.connected) {
+        return false;
+      }
+      try {
+        child.send(msg as Serializable);
+        return true;
+      } catch {
+        return false;
+      }
+    },
+
+    start: async (key: K) => {
+      const slot = getOrCreateSlot(key);
+      await enqueueOp(slot, async () => {
+        await forkAndWaitReady(slot);
+      });
+    },
+
+    evict: async (key: K, opts: WorkerDrainOpts | null) => {
+      const slot = getOrCreateSlot(key);
+      const shutdownMs = resolveShutdownTimeoutMs(opts);
+      await enqueueOp(slot, async () => {
+        await gracefulStop(slot, shutdownMs);
+        workers.delete(key);
+      });
+    },
+
+    drain: async (key: K, opts: WorkerDrainOpts | null) => {
+      const slot = getOrCreateSlot(key);
+      const shutdownMs = resolveShutdownTimeoutMs(opts);
+      await enqueueOp(slot, async () => {
+        if (slot.child === null) {
+          await forkAndWaitReady(slot);
+          return;
+        }
+        await gracefulStop(slot, shutdownMs);
+        await forkAndWaitReady(slot);
+      });
+    },
+
+    shutdown: async () => {
+      const snapshot = [...workers.values()];
+      await Promise.all(snapshot.map((slot) => enqueueOp(slot, () => shutdownWorker(slot))));
+    },
+
+    has: (key: K) => {
+      const slot = workers.get(key);
+      return slot !== undefined && isActive(slot);
+    },
+
+    hasDisconnectedChild: (key: K): boolean => {
+      const slot = workers.get(key);
+      if (slot === undefined || slot.child === null) {
+        return false;
+      }
+      return !slot.child.connected;
+    },
+
+    pid: (key: K) => {
+      const slot = workers.get(key);
+      if (slot === undefined || !isActive(slot) || slot.pid === null) {
+        return null;
+      }
+      return slot.pid;
+    },
+
+    keys: () => [...workers.values()].filter((slot) => isActive(slot)).map((slot) => slot.key),
+
+    stderrTail: (key: K) => {
+      const slot = workers.get(key);
+      return slot === undefined ? "" : slot.stderrTail;
+    },
+  };
+}

packages/daemon/src/workflow-manager-support.ts

@@ -0,0 +1,256 @@
+/**
+ * Pure helpers and IPC branching for workflow-manager (keeps workflow-manager.ts lean).
+ */
+
+import { dirname, join } from "node:path";
+import { fileURLToPath } from "node:url";
+
+import type { WorkflowMessage } from "@uncaged/nerve-core";
+import { START, isPlainRecord } from "@uncaged/nerve-core";
+
+import type { LogStore, WorkflowRunStatus } from "@uncaged/nerve-store";
+import type { ResumeThreadMessage, ThreadEventMessage } from "./ipc.js";
+import type { WorkerToParentMessage } from "./ipc.js";
+
+export type PendingThread = {
+  runId: string;
+  prompt: string;
+  maxRounds: number;
+  dryRun: boolean;
+};
+
+export type WorkflowState = {
+  active: Set<string>;
+  queue: PendingThread[];
+};
+
+/** Matches legacy manager: 6 crashes within 60s stops respawn (was `length > 5`). */
+export const WORKFLOW_WORKER_RESPAWN = {
+  enabled: true,
+  maxCrashes: 6,
+  windowMs: 60_000,
+  delayMs: 0,
+} as const;
+
+/**
+ * Worker shutdown timeout — must stay in sync with SHUTDOWN_TIMEOUT_MS in workflow-worker.ts.
+ * The drain timeout passed to drainAndRespawn must be >= this value so the worker has
+ * enough time to finish in-flight threads before the parent force-kills it.
+ */
+export const WORKER_SHUTDOWN_TIMEOUT_MS = 10_000;
+
+export const DEFAULT_MAX_QUEUE = 100;
+
+export function readLaunchFromTriggerPayload(
+  raw: unknown,
+  engineDefaultMaxRounds: number,
+): { prompt: string; maxRounds: number; dryRun: boolean } {
+  if (isPlainRecord(raw)) {
+    const o = raw;
+    if (typeof o.prompt === "string" && typeof o.maxRounds === "number") {
+      const dryRun = typeof o.dryRun === "boolean" ? o.dryRun : false;
+      return { prompt: o.prompt, maxRounds: o.maxRounds, dryRun };
+    }
+  }
+  return { prompt: "", maxRounds: engineDefaultMaxRounds, dryRun: false };
+}
+
+export function ensureThreadMessagesWithStart(
+  messages: Array<{ role: string; content: string; meta: unknown; timestamp: number }>,
+  threadId: string,
+  fallbackPrompt: string,
+  fallbackMaxRounds: number,
+): WorkflowMessage[] {
+  const mapped: WorkflowMessage[] = messages.map((m) => ({
+    role: m.role,
+    content: m.content,
+    meta: m.meta,
+    timestamp: m.timestamp,
+  }));
+  if (mapped.length > 0 && mapped[0].role === START) {
+    return mapped;
+  }
+  const start: WorkflowMessage = {
+    role: START,
+    content: fallbackPrompt,
+    meta: { maxRounds: fallbackMaxRounds, threadId },
+    timestamp: Date.now(),
+  };
+  return [start, ...mapped];
+}
+
+export function resolveWorkflowWorkerScript(): string {
+  const __filename = fileURLToPath(import.meta.url);
+  const __dir = dirname(__filename);
+  return join(__dir, "workflow-worker.js");
+}
+
+export function mapWorkflowRunStatus(eventType: string): WorkflowRunStatus | null {
+  const map: Record<string, WorkflowRunStatus> = {
+    started: "started",
+    queued: "queued",
+    completed: "completed",
+    failed: "failed",
+    crashed: "crashed",
+    dropped: "dropped",
+    interrupted: "interrupted",
+    killed: "killed",
+  };
+  return map[eventType] ?? null;
+}
+
+export function extractExitCodeFromPayload(payload: unknown): number | null {
+  if (isPlainRecord(payload) && typeof payload.exitCode === "number") {
+    return payload.exitCode;
+  }
+  return null;
+}
+
+export function appendWorkflowRunLog(
+  logStore: LogStore,
+  workflowName: string,
+  runId: string,
+  eventType: string,
+  payload: unknown | undefined,
+  exitCode: number | null,
+): void {
+  const timestamp = Date.now();
+  const serialised = payload !== undefined ? JSON.stringify(payload) : null;
+  const status = mapWorkflowRunStatus(eventType);
+
+  if (status !== null) {
+    logStore.upsertWorkflowRun(
+      {
+        source: "workflow",
+        type: eventType,
+        refId: runId,
+        payload: serialised,
+        timestamp,
+      },
+      { runId, workflow: workflowName, status, timestamp, exitCode },
+    );
+  } else {
+    logStore.append({
+      source: "workflow",
+      type: eventType,
+      refId: runId,
+      payload: serialised,
+      timestamp,
+    });
+  }
+}
+
+export function recoverQueuedRun(
+  workflowName: string,
+  runId: string,
+  state: WorkflowState,
+  logStore: LogStore,
+  engineMaxRounds: number,
+): void {
+  if (state.queue.some((q) => q.runId === runId)) return;
+  const launch = readLaunchFromTriggerPayload(logStore.getTriggerPayload(runId), engineMaxRounds);
+  state.queue.push({
+    runId,
+    prompt: launch.prompt,
+    maxRounds: launch.maxRounds,
+    dryRun: launch.dryRun,
+  });
+  process.stderr.write(
+    `[workflow-manager] crash-recovery: re-queued thread "${runId}" for "${workflowName}"\n`,
+  );
+}
+
+export function recoverStartedRun(
+  workflowName: string,
+  runId: string,
+  state: WorkflowState,
+  logStore: LogStore,
+  engineMaxRounds: number,
+  sendResume: (wf: string, msg: ResumeThreadMessage) => void,
+): void {
+  if (state.active.has(runId)) return;
+  const rawMessages = logStore.getThreadMessages(runId);
+  const launch = readLaunchFromTriggerPayload(logStore.getTriggerPayload(runId), engineMaxRounds);
+  const messages = ensureThreadMessagesWithStart(
+    rawMessages,
+    runId,
+    launch.prompt,
+    launch.maxRounds,
+  );
+  state.active.add(runId);
+  const msg: ResumeThreadMessage = {
+    type: "resume-thread",
+    runId,
+    messages,
+    maxRounds: launch.maxRounds,
+    dryRun: launch.dryRun,
+  };
+  sendResume(workflowName, msg);
+  process.stderr.write(
+    `[workflow-manager] crash-recovery: resuming thread "${runId}" for "${workflowName}" (${String(messages.length)} messages)\n`,
+  );
+}
+
+export function recoverThreadsFromStore(
+  workflowName: string,
+  logStore: LogStore,
+  engineMaxRounds: number,
+  getOrCreateState: (name: string) => WorkflowState,
+  sendResume: (wf: string, msg: ResumeThreadMessage) => void,
+): void {
+  const activeRuns = logStore.getActiveWorkflowRuns(workflowName);
+  const state = getOrCreateState(workflowName);
+
+  for (const run of activeRuns) {
+    if (run.status === "queued") {
+      recoverQueuedRun(workflowName, run.runId, state, logStore, engineMaxRounds);
+    } else if (run.status === "started") {
+      recoverStartedRun(workflowName, run.runId, state, logStore, engineMaxRounds, sendResume);
+    }
+  }
+}
+
+export type WorkflowManagerMessageDeps = {
+  logStore: LogStore;
+  handleThreadEvent: (workflowName: string, msg: ThreadEventMessage) => void;
+  onWorkflowRoleError: (
+    workflowName: string,
+    runId: string,
+    error: string,
+    exitCode: number,
+  ) => void;
+};
+
+export function dispatchWorkflowWorkerMessage(
+  workflowName: string,
+  msg: WorkerToParentMessage,
+  deps: WorkflowManagerMessageDeps,
+): void {
+  if (msg.type === "thread-event") {
+    deps.handleThreadEvent(workflowName, msg);
+    return;
+  }
+
+  if (msg.type === "thread-workflow-message") {
+    deps.logStore.append({
+      source: "workflow",
+      type: "thread_workflow_message",
+      refId: msg.runId,
+      payload: JSON.stringify(msg.message),
+      timestamp: Date.now(),
+    });
+    return;
+  }
+
+  if (msg.type === "workflow-error") {
+    process.stderr.write(
+      `[workflow-manager] workflow-error for runId "${msg.runId}" in "${workflowName}": ${msg.error}\n`,
+    );
+    deps.onWorkflowRoleError(workflowName, msg.runId, msg.error, msg.exitCode);
+    return;
+  }
+
+  if (msg.type === "error") {
+    process.stderr.write(`[workflow-manager] error from "${workflowName}" worker: ${msg.error}\n`);
+  }
+}

packages/daemon/src/workflow-manager.ts

@@ -6,33 +6,24 @@
  * Concurrency and overflow (drop/queue) are enforced here in the parent process.
  */
 
-import { fork } from "node:child_process";
-import type { ChildProcess } from "node:child_process";
-import { dirname, join } from "node:path";
-import { fileURLToPath } from "node:url";
+import type { NerveConfig, WorkflowConfig, WorkflowStatus } from "@uncaged/nerve-core";
 
-import type {
-  NerveConfig,
-  WorkflowConfig,
-  WorkflowMessage,
-  WorkflowStatus,
-} from "@uncaged/nerve-core";
-import { START, isPlainRecord } from "@uncaged/nerve-core";
-
-import type { LogStore, WorkflowRunStatus } from "@uncaged/nerve-store";
-import type {
-  KillThreadMessage,
-  ResumeThreadMessage,
-  ShutdownMessage,
-  StartThreadMessage,
-  ThreadEventMessage,
-} from "./ipc.js";
+import type { LogStore } from "@uncaged/nerve-store";
+import type { KillThreadMessage, StartThreadMessage, ThreadEventMessage } from "./ipc.js";
 import { parseWorkerMessage } from "./ipc.js";
+import { formatCapturedStderrTail, formatChildExitSummary } from "./worker-fork-support.js";
+import { createWorkerRuntime } from "./worker-runtime.js";
 import {
-  formatCapturedStderrTail,
-  formatChildExitSummary,
-  teeCapturedStderr,
-} from "./worker-fork-support.js";
+  DEFAULT_MAX_QUEUE,
+  WORKER_SHUTDOWN_TIMEOUT_MS,
+  WORKFLOW_WORKER_RESPAWN,
+  type WorkflowState,
+  appendWorkflowRunLog,
+  dispatchWorkflowWorkerMessage,
+  extractExitCodeFromPayload,
+  recoverThreadsFromStore,
+  resolveWorkflowWorkerScript,
+} from "./workflow-manager-support.js";
 
 export type WorkflowLaunchParams = {
   prompt: string;
@@ -74,169 +65,109 @@ export type WorkflowManager = {
   stop: () => Promise<void>;
 };
 
-type PendingThread = {
-  runId: string;
-  prompt: string;
-  maxRounds: number;
-  dryRun: boolean;
-};
-
-type WorkflowState = {
-  active: Set<string>;
-  queue: PendingThread[];
-};
-
-type WorkerEntry = {
-  workflowName: string;
-  process: ChildProcess;
-  stopping: boolean;
-  /** When set, the worker is draining before a hot-reload respawn. */
-  draining: boolean;
-  stderrTail: { value: string };
-};
-
-// Crash respawn backoff: track crash timestamps per workflow.
-const MAX_CRASHES_IN_WINDOW = 5;
-const CRASH_WINDOW_MS = 60_000;
-
-/**
- * Worker shutdown timeout — must stay in sync with SHUTDOWN_TIMEOUT_MS in workflow-worker.ts.
- * The drain timeout passed to drainAndRespawn must be >= this value so the worker has
- * enough time to finish in-flight threads before the parent force-kills it.
- */
-const WORKER_SHUTDOWN_TIMEOUT_MS = 10_000;
-
-const DEFAULT_MAX_QUEUE = 100;
-
-function readLaunchFromTriggerPayload(
-  raw: unknown,
-  engineDefaultMaxRounds: number,
-): { prompt: string; maxRounds: number; dryRun: boolean } {
-  if (isPlainRecord(raw)) {
-    const o = raw;
-    if (typeof o.prompt === "string" && typeof o.maxRounds === "number") {
-      const dryRun = typeof o.dryRun === "boolean" ? o.dryRun : false;
-      return { prompt: o.prompt, maxRounds: o.maxRounds, dryRun };
-    }
-  }
-  return { prompt: "", maxRounds: engineDefaultMaxRounds, dryRun: false };
-}
-
-function ensureThreadMessagesWithStart(
-  messages: Array<{ role: string; content: string; meta: unknown; timestamp: number }>,
-  threadId: string,
-  fallbackPrompt: string,
-  fallbackMaxRounds: number,
-): WorkflowMessage[] {
-  const mapped: WorkflowMessage[] = messages.map((m) => ({
-    role: m.role,
-    content: m.content,
-    meta: m.meta,
-    timestamp: m.timestamp,
-  }));
-  if (mapped.length > 0 && mapped[0].role === START) {
-    return mapped;
-  }
-  const start: WorkflowMessage = {
-    role: START,
-    content: fallbackPrompt,
-    meta: { maxRounds: fallbackMaxRounds, threadId },
-    timestamp: Date.now(),
-  };
-  return [start, ...mapped];
-}
-
-function resolveWorkerScript(): string {
-  const __filename = fileURLToPath(import.meta.url);
-  const __dir = dirname(__filename);
-  return join(__dir, "workflow-worker.js");
-}
-
-function spawnWorkflowWorker(
-  nerveRoot: string,
-  workflowName: string,
-  workerScript: string,
-  stderrTail: { value: string },
-): ChildProcess {
-  const child = fork(workerScript, ["--workflow", workflowName, "--root", nerveRoot], {
-    stdio: ["ignore", "inherit", "pipe", "ipc"],
-  });
-  teeCapturedStderr(child, stderrTail);
-  // Prevent unhandled EPIPE when writing to a child whose IPC channel closed
-  child.on("error", (err) => {
-    if ((err as NodeJS.ErrnoException).code !== "EPIPE") {
-      console.error("[worker] error:", err.message);
-    }
-  });
-  return child;
-}
-
-function sendStartThread(worker: ChildProcess, msg: StartThreadMessage): void {
-  if (worker.connected === false) return;
-  try {
-    worker.send(msg);
-  } catch {
-    // IPC channel closed between connected check and send
-  }
-}
-
-function sendShutdown(worker: ChildProcess, entry: WorkerEntry): void {
-  entry.stopping = true;
-  if (worker.connected === false) return;
-  const msg: ShutdownMessage = { type: "shutdown" };
-  try {
-    worker.send(msg);
-  } catch {
-    // IPC channel closed between connected check and send
-  }
-}
-
-function sendResumeThread(worker: ChildProcess, msg: ResumeThreadMessage): void {
-  if (worker.connected === false) return;
-  try {
-    worker.send(msg);
-  } catch {
-    // IPC channel closed between connected check and send
-  }
-}
-
-function sendKillThread(worker: ChildProcess, runId: string): void {
-  if (worker.connected === false) return;
-  const msg: KillThreadMessage = { type: "kill-thread", runId };
-  try {
-    worker.send(msg);
-  } catch {
-    // IPC channel closed between connected check and send
-  }
-}
-
-function waitForExit(child: ChildProcess, timeoutMs: number): Promise<void> {
-  return new Promise((resolve) => {
-    const timer = setTimeout(() => {
-      child.kill("SIGKILL");
-      resolve();
-    }, timeoutMs);
-    child.once("exit", () => {
-      clearTimeout(timer);
-      resolve();
-    });
-  });
-}
-
 export function createWorkflowManager(
   nerveRoot: string,
   initialConfig: NerveConfig,
   logStore: LogStore,
 ): WorkflowManager {
-  const workerScript = resolveWorkerScript();
+  const workerScript = resolveWorkflowWorkerScript();
+
+  /**
+   * Default drain timeout must be at least WORKER_SHUTDOWN_TIMEOUT_MS so the worker
+   * has enough time to finish in-flight threads before the parent force-kills it.
+   */
+  const DEFAULT_DRAIN_TIMEOUT_MS = Math.max(30_000, WORKER_SHUTDOWN_TIMEOUT_MS + 5_000);
 
   const states = new Map<string, WorkflowState>();
-  const workers = new Map<string, WorkerEntry>();
-  const crashTimestamps = new Map<string, number[]>();
+  const trackedWorkflows = new Set<string>();
+  const hotReloadEvicting = new Set<string>();
+  const crashRecoveryPending = new Set<string>();
+  const crashLimitBlocked = new Set<string>();
   let stopped = false;
   let config = initialConfig;
   const pendingDrains = new Set<string>();
 
+  function logWorkflowEvent(
+    workflowName: string,
+    runId: string,
+    eventType: string,
+    payload: unknown | null = null,
+    exitCode: number | null = null,
+  ): void {
+    appendWorkflowRunLog(logStore, workflowName, runId, eventType, payload, exitCode);
+  }
+
+  const runtime = createWorkerRuntime<string>({
+    script: workerScript,
+    argsForKey: (workflowName) => ["--workflow", workflowName, "--root", nerveRoot],
+    forwardStderr: true,
+    onMessage: (workflowName, raw) => {
+      handleWorkerMessage(workflowName, raw);
+    },
+    onReady: (workflowName, _msg) => {
+      if (crashRecoveryPending.has(workflowName)) {
+        crashRecoveryPending.delete(workflowName);
+        recoverThreadsFromStore(
+          workflowName,
+          logStore,
+          config.maxRounds,
+          getOrCreateState,
+          (wf, msg) => {
+            sendToWorker(wf, msg);
+          },
+        );
+      }
+    },
+    onExit: (workflowName, code, signalStr) => {
+      const sig =
+        signalStr === null || signalStr === undefined || signalStr === ""
+          ? null
+          : (signalStr as NodeJS.Signals);
+
+      if (hotReloadEvicting.has(workflowName)) {
+        hotReloadEvicting.delete(workflowName);
+        markActiveRunsInterrupted(workflowName);
+        if (!stopped && workflowConfig(workflowName) !== null) {
+          process.stderr.write(
+            `[workflow-manager] worker for "${workflowName}" drained, respawning\n`,
+          );
+        }
+        return;
+      }
+
+      if (stopped) {
+        const state = states.get(workflowName);
+        if (state !== undefined) {
+          state.active.clear();
+        }
+        crashRecoveryPending.delete(workflowName);
+        return;
+      }
+
+      const summary = formatChildExitSummary(code, sig);
+      const stderrExtra = formatCapturedStderrTail(runtime.stderrTail(workflowName));
+      process.stderr.write(
+        `[workflow-manager] worker for "${workflowName}" exited (${summary})${stderrExtra}\n`,
+      );
+
+      cleanupAfterUnexpectedWorkerExit(workflowName);
+      crashRecoveryPending.add(workflowName);
+    },
+    onCrashLimitReached: (workflowName) => {
+      crashRecoveryPending.delete(workflowName);
+      trackedWorkflows.delete(workflowName);
+      crashLimitBlocked.add(workflowName);
+      process.stderr.write(
+        `[workflow-manager] worker for "${workflowName}" exceeded crash limit (${String(WORKFLOW_WORKER_RESPAWN.maxCrashes)} in ${String(WORKFLOW_WORKER_RESPAWN.windowMs)}ms) — stopping respawn\n`,
+      );
+    },
+    respawn: {
+      ...WORKFLOW_WORKER_RESPAWN,
+      allowRespawn: (_wf) => !stopped,
+    },
+    shutdownTimeoutMs: DEFAULT_DRAIN_TIMEOUT_MS,
+  });
+
   function getOrCreateState(workflowName: string): WorkflowState {
     let state = states.get(workflowName);
     if (state === undefined) {
@@ -250,60 +181,38 @@ export function createWorkflowManager(
     return config.workflows[workflowName] ?? null;
   }
 
-  function toWorkflowRunStatus(eventType: string): WorkflowRunStatus | null {
-    const map: Record<string, WorkflowRunStatus> = {
-      started: "started",
-      queued: "queued",
-      completed: "completed",
-      failed: "failed",
-      crashed: "crashed",
-      dropped: "dropped",
-      interrupted: "interrupted",
-      killed: "killed",
-    };
-    return map[eventType] ?? null;
-  }
-
-  function extractExitCode(payload: unknown): number | null {
-    if (isPlainRecord(payload) && typeof payload.exitCode === "number") {
-      return payload.exitCode;
+  /** IPC send — matches legacy pool: no-op when IPC is disconnected; cold-start via WorkerRuntime.send. */
+  function sendToWorker(workflowName: string, msg: unknown): void {
+    if (crashLimitBlocked.has(workflowName)) {
+      return;
     }
-    return null;
-  }
-
-  function logWorkflowEvent(
-    workflowName: string,
-    runId: string,
-    eventType: string,
-    payload?: unknown,
-    exitCode: number | null = null,
-  ): void {
-    const timestamp = Date.now();
-    const serialised = payload !== undefined ? JSON.stringify(payload) : null;
-    const status = toWorkflowRunStatus(eventType);
-
-    if (status !== null) {
-      logStore.upsertWorkflowRun(
-        {
-          source: "workflow",
-          type: eventType,
-          refId: runId,
-          payload: serialised,
-          timestamp,
-        },
-        { runId, workflow: workflowName, status, timestamp, exitCode },
-      );
-    } else {
-      logStore.append({
-        source: "workflow",
-        type: eventType,
-        refId: runId,
-        payload: serialised,
-        timestamp,
+    trackedWorkflows.add(workflowName);
+    if (runtime.hasDisconnectedChild(workflowName)) {
+      return;
+    }
+    if (!runtime.trySendSync(workflowName, msg)) {
+      void runtime.send(workflowName, msg).catch(() => {
+        // IPC channel closed — mark any thread from this message as failed
+        if (isStartThreadMsg(msg)) {
+          const state = states.get(workflowName);
+          if (state?.active.has(msg.runId)) {
+            state.active.delete(msg.runId);
+            logWorkflowEvent(workflowName, msg.runId, "failed", { error: "IPC channel closed" }, 1);
+            dequeueNext(workflowName);
+          }
+        }
       });
     }
   }
 
+  function isStartThreadMsg(msg: unknown): msg is StartThreadMessage {
+    return (
+      msg !== null &&
+      typeof msg === "object" &&
+      (msg as Record<string, unknown>).type === "start-thread"
+    );
+  }
+
   function dispatchThread(
     workflowName: string,
     runId: string,
@@ -314,7 +223,6 @@ export function createWorkflowManager(
     const state = getOrCreateState(workflowName);
     state.active.add(runId);
 
-    const worker = getOrSpawnWorker(workflowName);
     const msg: StartThreadMessage = {
       type: "start-thread",
       runId,
@@ -323,7 +231,7 @@ export function createWorkflowManager(
       maxRounds,
       dryRun,
     };
-    sendStartThread(worker.process, msg);
+    sendToWorker(workflowName, msg);
     logWorkflowEvent(workflowName, runId, "started", { prompt, maxRounds, dryRun });
   }
 
@@ -367,92 +275,20 @@ export function createWorkflowManager(
     if (msg.eventType === "completed" || msg.eventType === "failed" || msg.eventType === "killed") {
       state.active.delete(msg.runId);
       dequeueNext(workflowName);
-      const exitCode = extractExitCode(msg.payload);
+      const exitCode = extractExitCodeFromPayload(msg.payload);
       logWorkflowEvent(workflowName, msg.runId, msg.eventType, msg.payload, exitCode);
       maybeDeferredHotReloadDrain(workflowName);
     }
   }
 
-  function recoverQueuedRun(workflowName: string, runId: string, state: WorkflowState): void {
-    if (state.queue.some((q) => q.runId === runId)) return;
-    const launch = readLaunchFromTriggerPayload(
-      logStore.getTriggerPayload(runId),
-      config.maxRounds,
-    );
-    state.queue.push({
-      runId,
-      prompt: launch.prompt,
-      maxRounds: launch.maxRounds,
-      dryRun: launch.dryRun,
-    });
-    process.stderr.write(
-      `[workflow-manager] crash-recovery: re-queued thread "${runId}" for "${workflowName}"\n`,
-    );
-  }
-
-  function recoverStartedRun(
-    workflowName: string,
-    runId: string,
-    state: WorkflowState,
-    worker: WorkerEntry,
-  ): void {
-    if (state.active.has(runId)) return;
-    const rawMessages = logStore.getThreadMessages(runId);
-    const launch = readLaunchFromTriggerPayload(
-      logStore.getTriggerPayload(runId),
-      config.maxRounds,
-    );
-    const messages = ensureThreadMessagesWithStart(
-      rawMessages,
-      runId,
-      launch.prompt,
-      launch.maxRounds,
-    );
-    state.active.add(runId);
-    const msg: ResumeThreadMessage = {
-      type: "resume-thread",
-      runId,
-      messages,
-      maxRounds: launch.maxRounds,
-      dryRun: launch.dryRun,
-    };
-    sendResumeThread(worker.process, msg);
-    process.stderr.write(
-      `[workflow-manager] crash-recovery: resuming thread "${runId}" for "${workflowName}" (${messages.length} messages)\n`,
-    );
-  }
-
-  function recoverThreadsForWorker(workflowName: string, worker: WorkerEntry): void {
-    const activeRuns = logStore.getActiveWorkflowRuns(workflowName);
-    const state = getOrCreateState(workflowName);
-
-    for (const run of activeRuns) {
-      if (run.status === "queued") {
-        recoverQueuedRun(workflowName, run.runId, state);
-      } else if (run.status === "started") {
-        recoverStartedRun(workflowName, run.runId, state, worker);
-      }
-    }
-  }
-
-  function recordCrashAndCheckLimit(workflowName: string): boolean {
-    const now = Date.now();
-    const timestamps = (crashTimestamps.get(workflowName) ?? []).filter(
-      (t) => now - t < CRASH_WINDOW_MS,
-    );
-    timestamps.push(now);
-    crashTimestamps.set(workflowName, timestamps);
-    return timestamps.length > MAX_CRASHES_IN_WINDOW;
-  }
-
-  function handleWorkerCrash(workflowName: string): void {
+  function cleanupAfterUnexpectedWorkerExit(workflowName: string): void {
     const state = states.get(workflowName);
     if (state === undefined) return;
 
     const crashedCount = state.active.size;
     if (crashedCount > 0) {
       process.stderr.write(
-        `[workflow-manager] worker for "${workflowName}" crashed with ${crashedCount} active thread(s)\n`,
+        `[workflow-manager] worker for "${workflowName}" crashed with ${String(crashedCount)} active thread(s)\n`,
       );
       for (const runId of state.active) {
         logWorkflowEvent(workflowName, runId, "crashed", undefined, 255);
@@ -460,26 +296,13 @@ export function createWorkflowManager(
     }
 
     state.active.clear();
-    workers.delete(workflowName);
     pendingDrains.delete(workflowName);
 
-    if (stopped || workflowConfig(workflowName) === null) return;
-
-    if (recordCrashAndCheckLimit(workflowName)) {
-      const count = crashTimestamps.get(workflowName)?.length ?? 0;
+    if (!stopped && !crashLimitBlocked.has(workflowName) && workflowConfig(workflowName) !== null) {
       process.stderr.write(
-        `[workflow-manager] worker for "${workflowName}" crashed ${count} times in ${CRASH_WINDOW_MS}ms — stopping respawn\n`,
+        `[workflow-manager] respawning worker for "${workflowName}" after crash\n`,
       );
-      return;
     }
-
-    process.stderr.write(
-      `[workflow-manager] respawning worker for "${workflowName}" after crash\n`,
-    );
-    const newWorker = getOrSpawnWorker(workflowName);
-    setImmediate(() => {
-      recoverThreadsForWorker(workflowName, newWorker);
-    });
   }
 
   function handleWorkerMessage(workflowName: string, raw: unknown): void {
@@ -490,43 +313,19 @@ export function createWorkflowManager(
       );
       return;
     }
-    const msg = result.value;
-
-    if (msg.type === "thread-event") {
-      handleThreadEvent(workflowName, msg);
-      return;
-    }
-
-    if (msg.type === "thread-workflow-message") {
-      logStore.append({
-        source: "workflow",
-        type: "thread_workflow_message",
-        refId: msg.runId,
-        payload: JSON.stringify(msg.message),
-        timestamp: Date.now(),
-      });
-      return;
-    }
-
-    if (msg.type === "workflow-error") {
-      process.stderr.write(
-        `[workflow-manager] workflow-error for runId "${msg.runId}" in "${workflowName}": ${msg.error}\n`,
-      );
-      const state = states.get(workflowName);
-      if (state !== undefined) {
-        state.active.delete(msg.runId);
-        dequeueNext(workflowName);
-      }
-      logWorkflowEvent(workflowName, msg.runId, "failed", { error: msg.error }, msg.exitCode);
-      maybeDeferredHotReloadDrain(workflowName);
-      return;
-    }
-
-    if (msg.type === "error") {
-      process.stderr.write(
-        `[workflow-manager] error from "${workflowName}" worker: ${msg.error}\n`,
-      );
-    }
+    dispatchWorkflowWorkerMessage(workflowName, result.value, {
+      logStore,
+      handleThreadEvent,
+      onWorkflowRoleError: (wf, runId, error, exitCode) => {
+        const state = states.get(wf);
+        if (state !== undefined) {
+          state.active.delete(runId);
+          dequeueNext(wf);
+        }
+        logWorkflowEvent(wf, runId, "failed", { error }, exitCode);
+        maybeDeferredHotReloadDrain(wf);
+      },
+    });
   }
 
   function markActiveRunsInterrupted(workflowName: string): void {
@@ -538,67 +337,6 @@ export function createWorkflowManager(
     state.active.clear();
   }
 
-  function handleWorkerExit(
-    workflowName: string,
-    code: number | null,
-    signal: NodeJS.Signals | null,
-  ): void {
-    const entry = workers.get(workflowName);
-    if (entry?.draining) {
-      workers.delete(workflowName);
-      markActiveRunsInterrupted(workflowName);
-      if (!stopped && workflowConfig(workflowName) !== null) {
-        process.stderr.write(
-          `[workflow-manager] worker for "${workflowName}" drained, respawning\n`,
-        );
-        getOrSpawnWorker(workflowName);
-      }
-      return;
-    }
-    if (entry?.stopping) {
-      workers.delete(workflowName);
-      const state = states.get(workflowName);
-      if (state !== undefined) {
-        state.active.clear();
-      }
-      return;
-    }
-    const summary = formatChildExitSummary(code, signal);
-    const stderrExtra = entry !== undefined ? formatCapturedStderrTail(entry.stderrTail.value) : "";
-    process.stderr.write(
-      `[workflow-manager] worker for "${workflowName}" exited (${summary})${stderrExtra}\n`,
-    );
-    handleWorkerCrash(workflowName);
-  }
-
-  function getOrSpawnWorker(workflowName: string): WorkerEntry {
-    const existing = workers.get(workflowName);
-    if (existing !== undefined && existing.process.exitCode === null) {
-      return existing;
-    }
-
-    const stderrTail = { value: "" };
-    const child = spawnWorkflowWorker(nerveRoot, workflowName, workerScript, stderrTail);
-
-    child.on("message", (raw: unknown) => {
-      handleWorkerMessage(workflowName, raw);
-    });
-
-    child.on("exit", (code, signal) => {
-      handleWorkerExit(workflowName, code, signal ?? null);
-    });
-
-    const entry: WorkerEntry = {
-      workflowName,
-      process: child,
-      stopping: false,
-      draining: false,
-      stderrTail,
-    };
-    workers.set(workflowName, entry);
-    return entry;
-  }
-
   function killThread(runId: string): boolean {
     for (const [workflowName, state] of states) {
       const queueIdx = state.queue.findIndex((q) => q.runId === runId);
@@ -609,10 +347,8 @@ export function createWorkflowManager(
       }
 
       if (state.active.has(runId)) {
-        const workerEntry = workers.get(workflowName);
-        if (workerEntry !== undefined) {
-          sendKillThread(workerEntry.process, runId);
-        }
+        const msg: KillThreadMessage = { type: "kill-thread", runId };
+        sendToWorker(workflowName, msg);
         return true;
       }
     }
@@ -663,7 +399,7 @@ export function createWorkflowManager(
     state.queue.push({ runId, prompt, maxRounds, dryRun });
     logWorkflowEvent(workflowName, runId, "queued");
     process.stderr.write(
-      `[workflow-manager] queued thread for "${workflowName}" runId "${runId}" (queue length: ${state.queue.length})\n`,
+      `[workflow-manager] queued thread for "${workflowName}" runId "${runId}" (queue length: ${String(state.queue.length)})\n`,
     );
   }
 
@@ -707,35 +443,29 @@ export function createWorkflowManager(
     config = newConfig;
   }
 
-  /**
-   * Default drain timeout must be at least WORKER_SHUTDOWN_TIMEOUT_MS so the worker
-   * has enough time to finish in-flight threads before the parent force-kills it.
-   */
-  const DEFAULT_DRAIN_TIMEOUT_MS = Math.max(30_000, WORKER_SHUTDOWN_TIMEOUT_MS + 5_000);
-
   async function drainAndRespawn(
     workflowName: string,
     drainTimeoutMs: number = DEFAULT_DRAIN_TIMEOUT_MS,
   ): Promise<void> {
-    const entry = workers.get(workflowName);
-    if (entry === undefined) {
-      // No active worker — nothing to drain
+    if (!trackedWorkflows.has(workflowName)) {
       return;
     }
 
-    entry.draining = true;
-    // Send shutdown without setting stopping=true (so the exit handler uses the draining branch)
-    if (entry.process.connected) {
-      const msg: ShutdownMessage = { type: "shutdown" };
-      try {
-        entry.process.send(msg);
-      } catch {
-        // IPC closed
+    const shutdownMs = Math.max(drainTimeoutMs, WORKER_SHUTDOWN_TIMEOUT_MS);
+    hotReloadEvicting.add(workflowName);
+    try {
+      await runtime.evict(workflowName, { shutdownTimeoutMs: shutdownMs });
+      trackedWorkflows.delete(workflowName);
+
+      if (!stopped && workflowConfig(workflowName) !== null) {
+        trackedWorkflows.add(workflowName);
+        await runtime.start(workflowName);
       }
+    } finally {
+      hotReloadEvicting.delete(workflowName);
     }
-    await waitForExit(entry.process, drainTimeoutMs);
-    // The exit handler (draining branch) will respawn the worker automatically
   }
+
   function drainWhenIdle(workflowName: string): void {
     const state = states.get(workflowName);
     const hasActiveRuns = state !== undefined && state.active.size > 0;
@@ -761,20 +491,17 @@ export function createWorkflowManager(
 
     pendingDrains.add(workflowName);
     process.stderr.write(
-      `[workflow-manager] deferring hot-reload for "${workflowName}" until ${state.active.size} active run(s) complete\n`,
+      `[workflow-manager] deferring hot-reload for "${workflowName}" until ${String(state.active.size)} active run(s) complete\n`,
     );
   }
 
   async function stop(): Promise<void> {
     stopped = true;
     pendingDrains.clear();
-    const exitPromises: Promise<void>[] = [];
-    for (const entry of workers.values()) {
-      sendShutdown(entry.process, entry);
-      exitPromises.push(waitForExit(entry.process, 5000));
-    }
-    await Promise.all(exitPromises);
-    workers.clear();
+    hotReloadEvicting.clear();
+    crashRecoveryPending.clear();
+    await runtime.shutdown();
+    trackedWorkflows.clear();
   }
 
   return {

packages/workflow-meta/src/develop-sense/roles/coder.ts

@@ -10,7 +10,7 @@ export type CoderMeta = z.infer<typeof coderMetaSchema>;
 
 export function coderPrompt({ threadId }: { threadId: string }): string {
   return `Read the workflow thread for the planner's sense design and any tester feedback: \`nerve thread ${threadId}\`
-Read the nerve-dev skill for sense file structure and conventions: \`cat node_modules/@uncaged/nerve-skills/nerve-dev/SKILL.md\`
+Read \`cat AGENT.md\` from the repository root, then \`CONVENTIONS.md\` and \`.knowledge/sense.md\` if present.
 
 ## Your task
 
@@ -20,21 +20,21 @@ Implement (or fix) the sense the planner designed. If there is tester feedback i
 
 You do NOT need to finish everything in one pass. You may return \`done: false\` to continue in the next iteration.
 
-## File structure for each sense
+## File structure for each sense (flat workspace)
 
-- \`senses/<name>/src/index.ts\` — TypeScript compute source; import schema as \`./schema.ts\`
+The workspace has **one root** \`package.json\` and root \`scripts/build.mjs\` (or equivalent) that bundles all senses. There is **no** per-sense \`package.json\`. Bundled output is \`dist/senses/<name>/index.js\` after a root build.
+
+- \`senses/<name>/src/index.ts\` — compute entry; import schema as \`./schema.ts\`
 - \`senses/<name>/src/schema.ts\` — Drizzle schema (TypeScript)
-- \`senses/<name>/migrations/\` — Drizzle migration files (at sense root, not inside src/)
-- \`senses/<name>/package.json\` — with esbuild build script
-- \`senses/<name>/index.js\` — bundled output generated by \`pnpm build\` (do NOT edit by hand)
+- \`senses/<name>/migrations/\` — SQL migration files (at sense root, not inside \`src/\`)
 
-Look at existing senses for the package.json template and patterns.
+Look at existing senses for patterns.
 
 ## When to return done: true
 
 Return \`done: true\` ONLY when ALL of the following are true:
 - All required files are created
-- \`pnpm install --no-cache && pnpm build\` succeeds (run it!)
+- From the **workspace root**, \`pnpm run build\` or \`npm run build\` succeeds (run it!) and \`dist/senses/<name>/index.js\` exists
 - \`nerve.yaml\` is updated with the sense config
 
 Return \`done: false\` if you made progress but there is still work to do.`;

packages/workflow-meta/src/develop-sense/roles/planner.ts

@@ -12,7 +12,7 @@ export function plannerPrompt({ threadId }: { threadId: string }): string {
   return `You are planning a new Nerve sense.
 
 Read the workflow thread for the user's request: \`nerve thread ${threadId}\`
-Read the nerve-dev skill for sense conventions: \`cat node_modules/@uncaged/nerve-skills/nerve-dev/SKILL.md\`
+Read the workspace guide: \`cat AGENT.md\` from the repository root (created by \`nerve init\`). Also read \`CONVENTIONS.md\` and \`.knowledge/sense.md\` if present. Optional skills live under \`.cursor/skills/\`.
 Also look at existing senses in the \`senses/\` directory for patterns.
 
 Pick a good kebab-case name for this sense. Produce a PLAN (not code) in markdown:

packages/workflow-meta/src/develop-sense/roles/tester.ts

@@ -17,21 +17,20 @@ export function testerPrompt({
 **IMPORTANT: The Nerve workspace is at \`${nerveRoot}\`. All paths below are relative to this directory. Always \`cd ${nerveRoot}\` first.**
 
 Read the workflow thread for context: \`nerve thread ${threadId}\`
-Read the nerve-dev skill for expected file structure: \`cat ${nerveRoot}/node_modules/@uncaged/nerve-skills/nerve-dev/SKILL.md\`
+Read \`cat ${nerveRoot}/AGENT.md\`, then \`${nerveRoot}/CONVENTIONS.md\` and \`${nerveRoot}/.knowledge/sense.md\` if they exist.
 
 Verify the full lifecycle in this order:
 
-1. **File check** — all required sense files exist:
+1. **File check** — all required sense files exist (no per-sense \`package.json\`):
    - \`senses/<name>/src/index.ts\`
    - \`senses/<name>/src/schema.ts\`
    - \`senses/<name>/migrations/\`
-   - \`senses/<name>/package.json\`
 
-2. **Build** — run inside the sense directory:
+2. **Build** — from the workspace root:
    \`\`\`
-   cd ${nerveRoot}/senses/<name> && pnpm install --no-cache && pnpm build
+   cd ${nerveRoot} && pnpm run build
    \`\`\`
-   Must produce \`index.js\` at sense root without errors.
+   (or \`npm run build\` per root \`package.json\`.) Must produce \`${nerveRoot}/dist/senses/<name>/index.js\` without errors.
 
 3. **Config check** — \`nerve validate\` passes, confirming nerve.yaml is valid.
 

packages/workflow-meta/src/develop-workflow/roles/coder.ts

@@ -10,7 +10,7 @@ export type CoderMeta = z.infer<typeof coderMetaSchema>;
 
 export function coderPrompt({ threadId }: { threadId: string }): string {
   return `Read the workflow thread to get the planner's design and any reviewer/tester/committer feedback: \`nerve thread ${threadId}\`
-Read the nerve-dev skill for workflow file structure and conventions: \`cat node_modules/@uncaged/nerve-skills/nerve-dev/SKILL.md\`
+Read \`cat AGENT.md\` from the repository root, then \`CONVENTIONS.md\` and \`.knowledge/workflow.md\` if present. Optional skills live under \`.cursor/skills/\`.
 Also look at existing workflows in the \`workflows/\` directory for patterns.
 
 ## Your task
@@ -29,15 +29,13 @@ You do NOT need to finish everything in one pass. You may return \`done: false\`
 2. Second pass: implement role logic
 3. Third pass: fix build/lint errors
 
-## Workflow file structure
+## Workflow file structure (flat workspace)
+
+The workspace has **one root** \`package.json\` and **one** root build (\`pnpm run build\` or \`npm run build\`), implemented by \`scripts/build.mjs\`, which emits bundles under \`dist/workflows/<name>/index.js\`. There is **no** per-workflow \`package.json\` or \`tsconfig.json\`.
 
 Each workflow must have:
-- \`workflows/<name>/index.ts\` — WorkflowDefinition default export
-- \`workflows/<name>/build.ts\` — factory function
-- \`workflows/<name>/moderator.ts\` — moderator + meta types
-- \`workflows/<name>/roles/<role>.ts\` — meta schema and prompt function per role
-- \`workflows/<name>/package.json\` — with esbuild build script
-- \`workflows/<name>/tsconfig.json\` — TypeScript config
+- \`workflows/<name>/index.ts\` — default export \`WorkflowDefinition\` (moderator and meta types typically live here or are imported from co-located modules)
+- \`workflows/<name>/roles/<role>.ts\` — one TypeScript file per role (schemas, prompts, \`createRole\` wiring, or plain async role functions)
 
 For **new workflows**, also update \`nerve.yaml\` with \`workflows.<name>\`.
 
@@ -53,7 +51,7 @@ For **new workflows**, also update \`nerve.yaml\` with \`workflows.<name>\`.
 
 Return \`done: true\` ONLY when ALL of the following are true:
 - All changes from the plan are implemented
-- \`cd workflows/<name> && pnpm install --no-cache && pnpm build\` succeeds (run it!)
+- From the **workspace root**, \`pnpm run build\` or \`npm run build\` succeeds (run it!) so \`dist/workflows/<name>/index.js\` is produced
 - No lint or type errors remain
 
 Return \`done: false\` if you made progress but there is still work to do, or if build/lint has errors you plan to fix in the next iteration.`;

packages/workflow-meta/src/develop-workflow/roles/planner.ts

@@ -12,18 +12,18 @@ export function plannerPrompt({ threadId }: { threadId: string }): string {
   return `You are a Nerve workflow planner. You can **create new workflows** or **modify existing ones**.
 
 Read the workflow thread for the user's request: \`nerve thread ${threadId}\`
-Read the nerve-dev skill for workflow conventions: \`cat node_modules/@uncaged/nerve-skills/nerve-dev/SKILL.md\`
+Read the workspace guide: \`cat AGENT.md\` from the repository root (created by \`nerve init\`). Also read \`CONVENTIONS.md\` if it exists; if \`.knowledge/workflow.md\` exists (e.g. Nerve monorepo), read it for layout and engine behavior. Optional Cursor skills live under \`.cursor/skills/\`.
 List existing workflows: \`ls workflows/\`
 
 ## Determine the task type
 
-1. If the user wants to **modify an existing workflow** — read its current code (\`cat workflows/<name>/moderator.ts\`, \`cat workflows/<name>/build.ts\`, \`ls workflows/<name>/roles/\`, etc.) and understand its current structure before planning changes.
+1. If the user wants to **modify an existing workflow** — read its current code (\`cat workflows/<name>/index.ts\`, \`ls workflows/<name>/roles/\`, \`cat workflows/<name>/roles/<role>.ts\`, etc.) and understand its current structure before planning changes.
 2. If the user wants to **create a new workflow** — look at existing workflows in \`workflows/\` for patterns to follow.
 
 ## Produce a PLAN (not code) in markdown
 
 For **new workflows**:
-- Workflow name (kebab-case)
+- Workflow name — **verb-first** kebab-case phrase (e.g. \`review-pull-request\`, \`deploy-staging\`), not a bare noun
 - Roles list (name, purpose, tool)
 - Flow transitions / moderator routing logic
 - Validation loops design

packages/workflow-meta/src/develop-workflow/roles/tester.ts

@@ -17,24 +17,22 @@ export function testerPrompt({
 **IMPORTANT: The Nerve workspace is at \`${nerveRoot}\`. All paths below are relative to this directory. Always \`cd ${nerveRoot}\` first.**
 
 Read the workflow thread for context: \`nerve thread ${threadId}\`
-Read the nerve-dev skill for expected file structure: \`cat ${nerveRoot}/node_modules/@uncaged/nerve-skills/nerve-dev/SKILL.md\`
+Read \`cat ${nerveRoot}/AGENT.md\`, then \`${nerveRoot}/CONVENTIONS.md\` and \`${nerveRoot}/.knowledge/workflow.md\` if they exist.
 
 Get the workflow name from the thread (the planner's output).
 
 Verify the full lifecycle in this order:
 
-1. **File check** — all required workflow files exist (under \`${nerveRoot}/\`):
+1. **File check** — all required workflow sources exist (under \`${nerveRoot}/\`):
    - \`workflows/<name>/index.ts\`
-   - \`workflows/<name>/build.ts\`
-   - \`workflows/<name>/moderator.ts\`
-   - \`workflows/<name>/roles/\` with one \`.ts\` file per role
-   - \`workflows/<name>/package.json\`
+   - \`workflows/<name>/roles/\` with one \`.ts\` file per role (flat files, not per-role packages)
+   - **No** \`workflows/<name>/package.json\` or \`tsconfig.json\` expected
 
-2. **Build** — run inside the workflow directory:
+2. **Build** — from the workspace root:
    \`\`\`
-   cd ${nerveRoot}/workflows/<name> && pnpm install --no-cache && pnpm build
+   cd ${nerveRoot} && pnpm run build
    \`\`\`
-   Must produce \`dist/index.js\` without errors.
+   (or \`npm run build\` if that is what the root \`package.json\` defines.) Must produce \`${nerveRoot}/dist/workflows/<name>/index.js\` without errors.
 
 3. **Config check** — \`cd ${nerveRoot} && nerve validate\` passes, confirming nerve.yaml is valid.