diff --git a/.cursor/rules/sync-readme.mdc b/.cursor/rules/sync-readme.mdc
new file mode 100644
index 0000000..e807006
--- /dev/null
+++ b/.cursor/rules/sync-readme.mdc
@@ -0,0 +1,67 @@
+# Sync README
+
+When updating README.md files in this monorepo, follow these conventions.
+
+## Scope
+
+- Root `README.md` — project overview and navigation hub
+- Per-package `packages/*/README.md` — each package self-contained
+
+## Root README Structure
+
+The root README should have these sections in order:
+
+1. **Title and one-liner** — stateless workflow engine driven by single-step CLI
+2. **Overview** — 2-3 paragraphs explaining what it does and key concepts
+3. **Architecture** — dependency layer diagram (text-based)
+4. **Packages** — table with ALL packages from packages/ directory, columns: Package, Description, Type (cli/lib/agent/app)
+5. **Quick Start** — install, build, register workflow, start thread, run step
+6. **CLI Reference** — brief command list, detailed usage in cli-workflow README
+7. **Development** — bun install / build / check / test
+
+## Per-Package README Structure
+
+Each package README should have:
+
+1. **Title** — package name
+2. **One-line description** — matching package.json
+3. **Overview** — what it does, where it sits in the architecture, dependencies
+4. **Installation** — bun add (for libs) or "included as binary" (for cli/agents)
+5. **API** (lib packages) — all exports from src/index.ts with type signatures, grouped by category, minimal usage examples
+6. **CLI Usage** (cli/agent packages) — command reference with examples
+7. **Internal Structure** — brief src/ file organization
+8. **Configuration** (if applicable)
+
+## Execution Steps
+
+### Step 1: Gather current state
+For each package read:
+- package.json (name, version, description, dependencies, bin)
+- src/index.ts (public API exports)
+- Existing README.md (preserve hand-written content worth keeping)
+
+### Step 2: Update root README
+- Ensure ALL packages in packages/ directory are listed in the table
+- Update CLI command reference from uwf --help output
+- Keep Quick Start examples valid
+
+### Step 3: Write/update each package README
+- Follow the per-package structure
+- API section MUST match actual src/index.ts exports — never invent
+- For agent packages: document CLI binary name, how it is invoked
+- For lib packages: document exported types and functions
+- Internal structure: list actual files in src/
+
+### Step 4: Verify
+- All relative links work
+- Package names match package.json
+- No references to removed/renamed packages
+- bun run build still passes
+
+## Guidelines
+
+- Only document what src/index.ts actually exports
+- Root README summarizes, package READMEs go into detail
+- Verify CLI examples against actual commands
+- Preserve existing good prose when updating
+- English for all README content
diff --git a/packages/workflow-agent-builtin/__tests__/loop.test.ts b/packages/workflow-agent-builtin/__tests__/loop.test.ts
index f2c58dd..c1ea654 100644
--- a/packages/workflow-agent-builtin/__tests__/loop.test.ts
+++ b/packages/workflow-agent-builtin/__tests__/loop.test.ts
@@ -1,4 +1,4 @@
-import { describe, test, expect, mock, beforeEach } from "bun:test";
+import { beforeEach, describe, expect, mock, test } from "bun:test";
 
 const mockChatCompletionWithTools = mock(async () => ({
   content: "---\nstatus: done\n---",
@@ -19,7 +19,7 @@ mock.module("../src/tools/index.js", () => ({
   getBuiltinTools: () => [],
 }));
 
-import { shouldNudge, executeTurnTools, runBuiltinLoop } from "../src/loop.js";
+import { executeTurnTools, runBuiltinLoop, shouldNudge } from "../src/loop.js";
 
 const fakeProvider = {} as any;
 const fakeToolCtx = {} as any;
@@ -51,7 +51,9 @@ describe("shouldNudge", () => {
     expect(shouldNudge({ noTools: true, text: "some text", turn: 0, maxTurns: 5 })).toBe(false);
   });
   test("2.3 returns false when text starts with ---", () => {
-    expect(shouldNudge({ noTools: false, text: "---\nstatus: done", turn: 0, maxTurns: 5 })).toBe(false);
+    expect(shouldNudge({ noTools: false, text: "---\nstatus: done", turn: 0, maxTurns: 5 })).toBe(
+      false,
+    );
   });
   test("2.4 returns false on last turn", () => {
     expect(shouldNudge({ noTools: false, text: "some text", turn: 4, maxTurns: 5 })).toBe(false);
@@ -60,7 +62,9 @@ describe("shouldNudge", () => {
     expect(shouldNudge({ noTools: false, text: "some text", turn: 3, maxTurns: 5 })).toBe(true);
   });
   test("2.6 leading whitespace before --- suppresses nudge", () => {
-    expect(shouldNudge({ noTools: false, text: "  ---\nstatus: done", turn: 0, maxTurns: 5 })).toBe(false);
+    expect(shouldNudge({ noTools: false, text: "  ---\nstatus: done", turn: 0, maxTurns: 5 })).toBe(
+      false,
+    );
   });
 });
 
@@ -81,27 +85,42 @@ describe("executeTurnTools", () => {
   test("4.2 tool result content matches executeBuiltinTool return value", async () => {
     mockExecuteBuiltinTool.mockResolvedValue("result-A");
     const messages: any[] = [];
-    await executeTurnTools([{ id: "c1", name: "read_file", arguments: "{}" }], fakeToolCtx, messages, "/tmp", "sess");
+    await executeTurnTools(
+      [{ id: "c1", name: "read_file", arguments: "{}" }],
+      fakeToolCtx,
+      messages,
+      "/tmp",
+      "sess",
+    );
     expect(messages[0].content).toBe("result-A");
   });
 });
 
 describe("runBuiltinLoop integration", () => {
   test("3.1 single text-only response returns finalText immediately", async () => {
-    mockChatCompletionWithTools.mockResolvedValue({ content: "---\nstatus: done\n---", toolCalls: [] });
+    mockChatCompletionWithTools.mockResolvedValue({
+      content: "---\nstatus: done\n---",
+      toolCalls: [],
+    });
     const result = await runBuiltinLoop(makeOptions());
     expect(result.finalText).toBe("---\nstatus: done\n---");
     expect(result.turnCount).toBe(1);
   });
   test("3.2 noTools=true suppresses tool calls", async () => {
-    mockChatCompletionWithTools.mockResolvedValue({ content: "ok", toolCalls: [{ id: "c1", name: "read_file", arguments: "{}" }] });
+    mockChatCompletionWithTools.mockResolvedValue({
+      content: "ok",
+      toolCalls: [{ id: "c1", name: "read_file", arguments: "{}" }],
+    });
     const result = await runBuiltinLoop(makeOptions({ noTools: true }));
     expect(result.finalText).toBe("ok");
     expect(result.turnCount).toBe(1);
   });
   test("3.3 tool call followed by text response", async () => {
     mockChatCompletionWithTools
-      .mockResolvedValueOnce({ content: null, toolCalls: [{ id: "c1", name: "read_file", arguments: "{}" }] })
+      .mockResolvedValueOnce({
+        content: null,
+        toolCalls: [{ id: "c1", name: "read_file", arguments: "{}" }],
+      })
       .mockResolvedValueOnce({ content: "---\nstatus: done\n---", toolCalls: [] });
     mockExecuteBuiltinTool.mockResolvedValue("file contents");
     const result = await runBuiltinLoop(makeOptions());
@@ -115,7 +134,8 @@ describe("runBuiltinLoop integration", () => {
     const result = await runBuiltinLoop(makeOptions());
     expect(result.finalText).toBe("---\nstatus: done\n---");
     const nudgeMsg = result.messages.find(
-      (m) => m.role === "user" && typeof m.content === "string" && m.content.includes("frontmatter"),
+      (m) =>
+        m.role === "user" && typeof m.content === "string" && m.content.includes("frontmatter"),
     );
     expect(nudgeMsg).toBeDefined();
   });
@@ -125,7 +145,10 @@ describe("runBuiltinLoop integration", () => {
     expect(result.finalText).toBe("still thinking");
   });
   test("3.6 original messages array is not mutated", async () => {
-    mockChatCompletionWithTools.mockResolvedValue({ content: "---\nstatus: done\n---", toolCalls: [] });
+    mockChatCompletionWithTools.mockResolvedValue({
+      content: "---\nstatus: done\n---",
+      toolCalls: [],
+    });
     const original = [{ role: "system" as const, content: "sys" }];
     await runBuiltinLoop(makeOptions({ messages: original }));
     expect(original.length).toBe(1);