fix: throw on non-JSON Claude Code output instead of fallback

Claude Code CLI adapter for the workflow engine, mirroring
workflow-agent-hermes architecture. Spawns `claude -p` with
`--output-format json` for structured output parsing.

Refs #391

.workflows/solve-issue.yaml

@@ -20,8 +20,8 @@ roles:
       2. Revise the test spec accordingly
 
       After producing the test spec:
-      1. Store it via `uwf cas put "<markdown content>"` and capture the returned hash
-      2. Put the hash in meta.plan (required when status=ready)
+      1. Store it via `uwf cas put-text "<markdown content>"` and capture the returned hash
+      2. Put the hash in frontmatter.plan (required when status=ready)
     output: "Output a brief summary of the test spec. Frontmatter must include: status (ready or insufficient_info) and plan (CAS hash of the test spec, required when status=ready)."
     frontmatter:
       type: object

packages/cli-workflow/src/__tests__/thread-step-count.test.ts

@@ -0,0 +1,71 @@
+import { execFileSync } from "node:child_process";
+import { join } from "node:path";
+import { describe, expect, test } from "vitest";
+
+const CLI_PATH = join(import.meta.dirname, "..", "cli.js");
+
+function runCli(args: string[]): { stdout: string; stderr: string; exitCode: number } {
+  try {
+    const stdout = execFileSync("bun", ["run", CLI_PATH, ...args], {
+      encoding: "utf8",
+      env: { ...process.env, WORKFLOW_STORAGE_ROOT: "/tmp/uwf-test-nonexistent" },
+      stdio: ["ignore", "pipe", "pipe"],
+    });
+    return { stdout, stderr: "", exitCode: 0 };
+  } catch (e: unknown) {
+    const err = e as NodeJS.ErrnoException & { stdout?: string; stderr?: string; status?: number };
+    return {
+      stdout: err.stdout ?? "",
+      stderr: err.stderr ?? "",
+      exitCode: err.status ?? 1,
+    };
+  }
+}
+
+describe("thread step --count CLI parsing", () => {
+  test("--help shows -c/--count option", () => {
+    const result = runCli(["thread", "step", "--help"]);
+    expect(result.stdout).toContain("--count");
+    expect(result.stdout).toContain("-c");
+  });
+
+  test("description says 'one or more steps'", () => {
+    const result = runCli(["thread", "step", "--help"]);
+    expect(result.stdout).toContain("one or more steps");
+  });
+});
+
+describe("cmdThreadStep count logic", () => {
+  test("count=0 fails with validation error", () => {
+    const result = runCli(["thread", "step", "FAKE_THREAD_ID", "-c", "0"]);
+    expect(result.exitCode).not.toBe(0);
+    expect(result.stderr).toContain("positive integer");
+  });
+
+  test("negative count fails with validation error", () => {
+    const result = runCli(["thread", "step", "FAKE_THREAD_ID", "-c", "-1"]);
+    expect(result.exitCode).not.toBe(0);
+    expect(result.stderr).toContain("positive integer");
+  });
+
+  test("non-integer count fails with validation error", () => {
+    const result = runCli(["thread", "step", "FAKE_THREAD_ID", "-c", "1.5"]);
+    expect(result.exitCode).not.toBe(0);
+    expect(result.stderr).toContain("positive integer");
+  });
+
+  test("count=1 is the default (no -c flag)", () => {
+    // Without -c, it should attempt to run 1 step (failing on missing thread, not on count validation)
+    const result = runCli(["thread", "step", "FAKE_THREAD_ID"]);
+    expect(result.exitCode).not.toBe(0);
+    // Should NOT contain "positive integer" error — should fail on thread lookup instead
+    expect(result.stderr).not.toContain("positive integer");
+  });
+
+  test("count=3 passes validation (fails on thread lookup)", () => {
+    const result = runCli(["thread", "step", "FAKE_THREAD_ID", "-c", "3"]);
+    expect(result.exitCode).not.toBe(0);
+    // Should NOT contain "positive integer" error — should fail on thread/storage lookup
+    expect(result.stderr).not.toContain("positive integer");
+  });
+});

packages/cli-workflow/src/cli.ts

@@ -7,6 +7,7 @@ import {
   cmdCasGet,
   cmdCasHas,
   cmdCasPut,
+  cmdCasPutText,
   cmdCasRefs,
   cmdCasReindex,
   cmdCasSchemaGet,
@@ -108,15 +109,21 @@ thread
 
 thread
   .command("step")
-  .description("Execute one step")
+  .description("Execute one or more steps")
   .argument("<thread-id>", "Thread ULID")
   .option("--agent <cmd>", "Override agent command")
-  .action((threadId: string, opts: { agent: string | undefined }) => {
+  .option("-c, --count <number>", "Number of steps to run (default: 1)")
+  .action((threadId: string, opts: { agent: string | undefined; count: string | undefined }) => {
     const storageRoot = resolveStorageRoot();
     runAction(async () => {
       const agentOverride = opts.agent ?? null;
-      const result = await cmdThreadStep(storageRoot, threadId, agentOverride);
-      writeOutput(result);
+      const count = opts.count !== undefined ? Number(opts.count) : 1;
+      const results = await cmdThreadStep(storageRoot, threadId, agentOverride, count);
+      if (results.length === 1) {
+        writeOutput(results[0]);
+      } else {
+        writeOutput(results);
+      }
     });
   });
 
@@ -295,6 +302,17 @@ cas
     });
   });
 
+cas
+  .command("put-text")
+  .description("Store a plain text string, print its hash")
+  .argument("<text>", "Text content to store")
+  .action((text: string) => {
+    const storageRoot = resolveStorageRoot();
+    runAction(async () => {
+      writeOutput(await cmdCasPutText(storageRoot, text));
+    });
+  });
+
 cas
   .command("has")
   .description("Check if a hash exists")

packages/cli-workflow/src/commands/cas.ts

@@ -2,9 +2,11 @@ import { readFileSync } from "node:fs";
 import { join } from "node:path";
 
 import type { JSONSchema, Store } from "@uncaged/json-cas";
-import { bootstrap, getSchema, refs, walk } from "@uncaged/json-cas";
+import { bootstrap, getSchema, putSchema, refs, walk } from "@uncaged/json-cas";
 import { createFsStore } from "@uncaged/json-cas-fs";
 
+import { TEXT_SCHEMA } from "../schemas.js";
+
 // ---- Helpers ----
 
 function openStore(storageRoot: string): Store {
@@ -121,3 +123,10 @@ export async function cmdCasSchemaGet(storageRoot: string, hash: string): Promis
   }
   return schema;
 }
+
+export async function cmdCasPutText(storageRoot: string, text: string): Promise<{ hash: string }> {
+  const store = openStore(storageRoot);
+  const typeHash = await putSchema(store, TEXT_SCHEMA);
+  const hash = await store.put(typeHash, text);
+  return { hash };
+}

packages/cli-workflow/src/commands/thread.ts

@@ -673,6 +673,27 @@ export async function cmdThreadStep(
   storageRoot: string,
   threadId: ThreadId,
   agentOverride: string | null,
+  count: number,
+): Promise<StepOutput[]> {
+  if (count < 1 || !Number.isInteger(count)) {
+    fail(`--count must be a positive integer, got: ${count}`);
+  }
+
+  const results: StepOutput[] = [];
+  for (let i = 0; i < count; i++) {
+    const result = await cmdThreadStepOnce(storageRoot, threadId, agentOverride);
+    results.push(result);
+    if (result.done) {
+      break;
+    }
+  }
+  return results;
+}
+
+async function cmdThreadStepOnce(
+  storageRoot: string,
+  threadId: ThreadId,
+  agentOverride: string | null,
 ): Promise<StepOutput> {
   const index = await loadThreadsIndex(storageRoot);
   const headHash = index[threadId];

packages/cli-workflow/src/schemas.ts

@@ -2,10 +2,13 @@ import type { Hash, Store } from "@uncaged/json-cas";
 import { putSchema } from "@uncaged/json-cas";
 import { START_NODE_SCHEMA, STEP_NODE_SCHEMA, WORKFLOW_SCHEMA } from "@uncaged/workflow-protocol";
 
+export const TEXT_SCHEMA = { type: "string" as const };
+
 export type UwfSchemaHashes = {
   workflow: Hash;
   startNode: Hash;
   stepNode: Hash;
+  text: Hash;
 };
 
 /**
@@ -13,10 +16,11 @@ export type UwfSchemaHashes = {
  * Idempotent: safe to call on every CLI invocation.
  */
 export async function registerUwfSchemas(store: Store): Promise<UwfSchemaHashes> {
-  const [workflow, startNode, stepNode] = await Promise.all([
+  const [workflow, startNode, stepNode, text] = await Promise.all([
     putSchema(store, WORKFLOW_SCHEMA),
     putSchema(store, START_NODE_SCHEMA),
     putSchema(store, STEP_NODE_SCHEMA),
+    putSchema(store, TEXT_SCHEMA),
   ]);
-  return { workflow, startNode, stepNode };
+  return { workflow, startNode, stepNode, text };
 }

packages/workflow-agent-claude-code/__tests__/claude-code.test.ts

@@ -0,0 +1,59 @@
+import { describe, expect, test } from "bun:test";
+import type { AgentContext } from "@uncaged/workflow-agent-kit";
+import { buildClaudeCodePrompt } from "../src/claude-code.js";
+
+function makeCtx(overrides: Partial<AgentContext> = {}): AgentContext {
+  return {
+    workflow: {
+      roles: {
+        developer: {
+          description: "TDD implementation per test spec",
+          goal: "Write code",
+          capabilities: ["coding"],
+          procedure: "1. Read spec\n2. Write code",
+          output: "List files changed",
+          frontmatter: "",
+        },
+      },
+      conditions: {},
+      graph: {},
+    },
+    role: "developer",
+    start: { prompt: "Fix the bug", workflowHash: "abc123", threadId: "t1" },
+    steps: [],
+    store: {} as AgentContext["store"],
+    outputFormatInstruction: "Use YAML frontmatter",
+    ...overrides,
+  };
+}
+
+describe("buildClaudeCodePrompt", () => {
+  test("assembles outputFormatInstruction + role prompt + task prompt", () => {
+    const result = buildClaudeCodePrompt(makeCtx());
+    expect(result).toMatch(/^Use YAML frontmatter/);
+    expect(result).toContain("Write code");
+    expect(result).toContain("## Task\nFix the bug");
+  });
+
+  test("includes previous steps as history summary", () => {
+    const ctx = makeCtx({
+      steps: [{ role: "planner", output: '{"plan":"do X"}', agent: "hermes" }],
+    });
+    const result = buildClaudeCodePrompt(ctx);
+    expect(result).toContain("## Previous Steps");
+    expect(result).toContain("Step 1: planner");
+    expect(result).toContain("do X");
+  });
+
+  test("omits history section when steps array is empty", () => {
+    const result = buildClaudeCodePrompt(makeCtx({ steps: [] }));
+    expect(result).not.toContain("## Previous Steps");
+  });
+
+  test("works without outputFormatInstruction", () => {
+    const result = buildClaudeCodePrompt(makeCtx({ outputFormatInstruction: "" }));
+    expect(result).not.toMatch(/^\s*\n/);
+    expect(result).toContain("Write code");
+    expect(result).toContain("## Task");
+  });
+});

packages/workflow-agent-claude-code/__tests__/session-detail.test.ts

@@ -0,0 +1,115 @@
+import { describe, expect, test } from "bun:test";
+import { createMemoryStore, walk } from "@uncaged/json-cas";
+import {
+  parseClaudeCodeJsonOutput,
+  storeClaudeCodeDetail,
+  storeClaudeCodeRawOutput,
+} from "../src/session-detail.js";
+import type { ClaudeCodeParsedResult } from "../src/types.js";
+
+describe("parseClaudeCodeJsonOutput", () => {
+  test("parses valid claude -p --output-format json output", () => {
+    const stdout = JSON.stringify({
+      type: "result",
+      subtype: "success",
+      result: "Done fixing bug",
+      session_id: "75e2167f-abc",
+      num_turns: 3,
+      total_cost_usd: 0.08,
+      duration_ms: 10276,
+    });
+    const parsed = parseClaudeCodeJsonOutput(stdout);
+    expect(parsed).not.toBeNull();
+    expect(parsed!.type).toBe("result");
+    expect(parsed!.subtype).toBe("success");
+    expect(parsed!.result).toBe("Done fixing bug");
+    expect(parsed!.sessionId).toBe("75e2167f-abc");
+    expect(parsed!.numTurns).toBe(3);
+    expect(parsed!.totalCostUsd).toBe(0.08);
+    expect(parsed!.durationMs).toBe(10276);
+  });
+
+  test("parses error_max_turns result", () => {
+    const stdout = JSON.stringify({
+      type: "result",
+      subtype: "error_max_turns",
+      result: "Ran out of turns",
+      session_id: "abc-def",
+      num_turns: 90,
+      total_cost_usd: 1.5,
+      duration_ms: 50000,
+    });
+    const parsed = parseClaudeCodeJsonOutput(stdout);
+    expect(parsed).not.toBeNull();
+    expect(parsed!.subtype).toBe("error_max_turns");
+    expect(parsed!.result).toBe("Ran out of turns");
+  });
+
+  test("returns null for non-JSON output", () => {
+    const parsed = parseClaudeCodeJsonOutput("Some random text\nwithout JSON");
+    expect(parsed).toBeNull();
+  });
+
+  test("returns null when session_id is missing", () => {
+    const stdout = JSON.stringify({ type: "result", result: "hi", subtype: "success" });
+    const parsed = parseClaudeCodeJsonOutput(stdout);
+    expect(parsed).toBeNull();
+  });
+});
+
+describe("storeClaudeCodeDetail", () => {
+  test("stores claude-code-detail CAS node and returns output + detailHash", async () => {
+    const store = createMemoryStore();
+    const parsed: ClaudeCodeParsedResult = {
+      type: "result",
+      subtype: "success",
+      result: "The answer",
+      sessionId: "abc-123",
+      numTurns: 5,
+      totalCostUsd: 0.12,
+      durationMs: 15000,
+    };
+
+    const { detailHash, output, sessionId } = await storeClaudeCodeDetail(store, parsed);
+    expect(detailHash).toHaveLength(13);
+    expect(output).toBe("The answer");
+    expect(sessionId).toBe("abc-123");
+
+    const node = await store.get(detailHash);
+    expect(node).not.toBeNull();
+    expect(node!.payload.sessionId).toBe("abc-123");
+    expect(node!.payload.numTurns).toBe(5);
+    expect(node!.payload.totalCostUsd).toBe(0.12);
+    expect(node!.payload.durationMs).toBe(15000);
+  });
+
+  test("detail node is walkable from root", async () => {
+    const store = createMemoryStore();
+    const parsed: ClaudeCodeParsedResult = {
+      type: "result",
+      subtype: "success",
+      result: "walkable test",
+      sessionId: "walk-123",
+      numTurns: 1,
+      totalCostUsd: 0.01,
+      durationMs: 1000,
+    };
+
+    const { detailHash } = await storeClaudeCodeDetail(store, parsed);
+    const visited: string[] = [];
+    walk(store, detailHash, (hash) => visited.push(hash));
+    expect(visited.length).toBeGreaterThan(0);
+  });
+});
+
+describe("storeClaudeCodeRawOutput", () => {
+  test("stores raw text when JSON parsing fails", async () => {
+    const store = createMemoryStore();
+    const rawText = "Claude produced plain text without JSON";
+    const hash = await storeClaudeCodeRawOutput(store, rawText);
+    expect(hash).toHaveLength(13);
+    const node = await store.get(hash);
+    expect(node).not.toBeNull();
+    expect(node!.payload.text).toBe(rawText);
+  });
+});

packages/workflow-agent-claude-code/package.json

@@ -0,0 +1,33 @@
+{
+  "name": "@uncaged/workflow-agent-claude-code",
+  "version": "0.1.0",
+  "files": [
+    "src",
+    "dist",
+    "package.json"
+  ],
+  "type": "module",
+  "bin": {
+    "uwf-claude-code": "./src/cli.ts"
+  },
+  "exports": {
+    ".": {
+      "bun": "./src/index.ts",
+      "types": "./dist/index.d.ts",
+      "import": "./dist/index.js"
+    }
+  },
+  "scripts": {
+    "test": "bun test"
+  },
+  "dependencies": {
+    "@uncaged/json-cas": "^0.4.0",
+    "@uncaged/workflow-agent-kit": "workspace:^"
+  },
+  "devDependencies": {
+    "typescript": "^5.8.3"
+  },
+  "publishConfig": {
+    "access": "public"
+  }
+}

packages/workflow-agent-claude-code/src/claude-code.ts

@@ -0,0 +1,148 @@
+import { spawn } from "node:child_process";
+import type { Store } from "@uncaged/json-cas";
+
+import {
+  type AgentContext,
+  type AgentRunResult,
+  buildRolePrompt,
+  createAgent,
+} from "@uncaged/workflow-agent-kit";
+
+import { parseClaudeCodeJsonOutput, storeClaudeCodeDetail } from "./session-detail.js";
+
+const CLAUDE_COMMAND = "claude";
+const CLAUDE_MAX_TURNS = 90;
+
+function buildHistorySummary(steps: AgentContext["steps"]): string {
+  if (steps.length === 0) {
+    return "";
+  }
+
+  const lines: string[] = ["## Previous Steps"];
+  for (let i = 0; i < steps.length; i++) {
+    const step = steps[i];
+    if (step === undefined) {
+      continue;
+    }
+    lines.push("");
+    lines.push(`### Step ${i + 1}: ${step.role}`);
+    lines.push(`Output: ${JSON.stringify(step.output)}`);
+    lines.push(`Agent: ${step.agent}`);
+  }
+  return lines.join("\n");
+}
+
+/** Assemble system prompt, task, and prior step outputs for Claude Code. */
+export function buildClaudeCodePrompt(ctx: AgentContext): string {
+  const roleDef = ctx.workflow.roles[ctx.role];
+  const rolePrompt = roleDef !== undefined ? buildRolePrompt(roleDef) : "";
+  const parts: string[] = [];
+  if (ctx.outputFormatInstruction !== undefined && ctx.outputFormatInstruction !== "") {
+    parts.push(ctx.outputFormatInstruction, "");
+  }
+  parts.push(rolePrompt, "", "## Task", ctx.start.prompt);
+  const historyBlock = buildHistorySummary(ctx.steps);
+  if (historyBlock !== "") {
+    parts.push("", historyBlock);
+  }
+  return parts.join("\n");
+}
+
+function spawnClaude(args: string[]): Promise<{ stdout: string; stderr: string }> {
+  return new Promise((resolve, reject) => {
+    const child = spawn(CLAUDE_COMMAND, args, {
+      env: process.env,
+      shell: false,
+      stdio: ["ignore", "pipe", "pipe"],
+    });
+
+    let stdout = "";
+    let stderr = "";
+    child.stdout?.on("data", (chunk: Buffer) => {
+      stdout += chunk.toString();
+    });
+    child.stderr?.on("data", (chunk: Buffer) => {
+      stderr += chunk.toString();
+    });
+
+    child.on("error", (cause) => {
+      const message = cause instanceof Error ? cause.message : String(cause);
+      reject(new Error(`claude spawn failed: ${message}`));
+    });
+
+    child.on("close", (code) => {
+      if (code === 0) {
+        resolve({ stdout, stderr });
+        return;
+      }
+      const detail = stderr.trim() !== "" ? ` stderr=${stderr.trim()}` : "";
+      reject(new Error(`claude exited with code ${code ?? "null"}${detail}`));
+    });
+  });
+}
+
+function spawnClaudeRun(prompt: string): Promise<{ stdout: string; stderr: string }> {
+  return spawnClaude([
+    "-p",
+    prompt,
+    "--output-format",
+    "json",
+    "--dangerously-skip-permissions",
+    "--max-turns",
+    String(CLAUDE_MAX_TURNS),
+  ]);
+}
+
+function spawnClaudeResume(
+  sessionId: string,
+  message: string,
+): Promise<{ stdout: string; stderr: string }> {
+  return spawnClaude([
+    "-p",
+    message,
+    "--resume",
+    sessionId,
+    "--output-format",
+    "json",
+    "--dangerously-skip-permissions",
+    "--max-turns",
+    String(CLAUDE_MAX_TURNS),
+  ]);
+}
+
+async function processClaudeOutput(stdout: string, store: Store): Promise<AgentRunResult> {
+  const parsed = parseClaudeCodeJsonOutput(stdout);
+
+  if (parsed !== null) {
+    const { detailHash, output, sessionId } = await storeClaudeCodeDetail(store, parsed);
+    return { output, detailHash, sessionId };
+  }
+
+  throw new Error(
+    `Claude Code returned non-JSON output (first 200 chars): ${stdout.slice(0, 200)}`,
+  );
+}
+
+async function runClaudeCode(ctx: AgentContext): Promise<AgentRunResult> {
+  const fullPrompt = buildClaudeCodePrompt(ctx);
+  const { stdout } = await spawnClaudeRun(fullPrompt);
+  return processClaudeOutput(stdout, ctx.store);
+}
+
+async function continueClaudeCode(
+  sessionId: string,
+  message: string,
+  store: Store,
+): Promise<AgentRunResult> {
+  const { stdout } = await spawnClaudeResume(sessionId, message);
+  return processClaudeOutput(stdout, store);
+}
+
+/** Agent CLI factory: parses argv, runs Claude Code, extracts output, writes StepNode. */
+export function createClaudeCodeAgent(): () => Promise<void> {
+  return createAgent({
+    name: "claude-code",
+    run: runClaudeCode,
+    continue: continueClaudeCode,
+  });
+}

packages/workflow-agent-claude-code/src/cli.ts

@@ -0,0 +1,6 @@
+#!/usr/bin/env bun
+
+import { createClaudeCodeAgent } from "./claude-code.js";
+
+const main = createClaudeCodeAgent();
+void main();

packages/workflow-agent-claude-code/src/index.ts

@@ -0,0 +1,6 @@
+export { buildClaudeCodePrompt, createClaudeCodeAgent } from "./claude-code.js";
+export {
+  parseClaudeCodeJsonOutput,
+  storeClaudeCodeDetail,
+  storeClaudeCodeRawOutput,
+} from "./session-detail.js";

packages/workflow-agent-claude-code/src/schemas.ts

@@ -0,0 +1,25 @@
+import type { JSONSchema } from "@uncaged/json-cas";
+
+export const CLAUDE_CODE_DETAIL_SCHEMA: JSONSchema = {
+  title: "claude-code-detail",
+  type: "object",
+  required: ["sessionId", "numTurns", "totalCostUsd", "durationMs", "subtype"],
+  properties: {
+    sessionId: { type: "string" },
+    numTurns: { type: "integer" },
+    totalCostUsd: { type: "number" },
+    durationMs: { type: "integer" },
+    subtype: { type: "string" },
+  },
+  additionalProperties: false,
+};
+
+export const CLAUDE_CODE_RAW_OUTPUT_SCHEMA: JSONSchema = {
+  title: "claude-code-raw-output",
+  type: "object",
+  required: ["text"],
+  properties: {
+    text: { type: "string" },
+  },
+  additionalProperties: false,
+};

packages/workflow-agent-claude-code/src/session-detail.ts

@@ -0,0 +1,79 @@
+import { bootstrap, putSchema, type Store } from "@uncaged/json-cas";
+
+import { CLAUDE_CODE_DETAIL_SCHEMA, CLAUDE_CODE_RAW_OUTPUT_SCHEMA } from "./schemas.js";
+import type { ClaudeCodeDetailPayload, ClaudeCodeParsedResult } from "./types.js";
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null && !Array.isArray(value);
+}
+
+/** Parse Claude Code JSON stdout (`claude -p --output-format json`). */
+export function parseClaudeCodeJsonOutput(stdout: string): ClaudeCodeParsedResult | null {
+  let parsed: unknown;
+  try {
+    parsed = JSON.parse(stdout.trim());
+  } catch {
+    return null;
+  }
+
+  if (!isRecord(parsed)) {
+    return null;
+  }
+
+  const sessionId = parsed.session_id;
+  const result = parsed.result;
+  const subtype = parsed.subtype;
+
+  if (typeof sessionId !== "string" || typeof result !== "string" || typeof subtype !== "string") {
+    return null;
+  }
+
+  return {
+    type: typeof parsed.type === "string" ? parsed.type : "result",
+    subtype: subtype as ClaudeCodeParsedResult["subtype"],
+    result,
+    sessionId,
+    numTurns: typeof parsed.num_turns === "number" ? parsed.num_turns : 0,
+    totalCostUsd: typeof parsed.total_cost_usd === "number" ? parsed.total_cost_usd : 0,
+    durationMs: typeof parsed.duration_ms === "number" ? parsed.duration_ms : 0,
+  };
+}
+
+type ClaudeCodeSchemaHashes = {
+  detail: string;
+  rawOutput: string;
+};
+
+async function registerSchemas(store: Store): Promise<ClaudeCodeSchemaHashes> {
+  await bootstrap(store);
+  const [detail, rawOutput] = await Promise.all([
+    putSchema(store, CLAUDE_CODE_DETAIL_SCHEMA),
+    putSchema(store, CLAUDE_CODE_RAW_OUTPUT_SCHEMA),
+  ]);
+  return { detail, rawOutput };
+}
+
+/** Store parsed Claude Code result as a CAS detail node. */
+export async function storeClaudeCodeDetail(
+  store: Store,
+  parsed: ClaudeCodeParsedResult,
+): Promise<{ detailHash: string; output: string; sessionId: string }> {
+  const schemas = await registerSchemas(store);
+
+  const detail: ClaudeCodeDetailPayload = {
+    sessionId: parsed.sessionId,
+    numTurns: parsed.numTurns,
+    totalCostUsd: parsed.totalCostUsd,
+    durationMs: parsed.durationMs,
+    subtype: parsed.subtype,
+  };
+
+  const detailHash = await store.put(schemas.detail, detail);
+  return { detailHash, output: parsed.result, sessionId: parsed.sessionId };
+}
+
+/** Fallback: store raw text output when JSON parsing fails. */
+export async function storeClaudeCodeRawOutput(store: Store, rawOutput: string): Promise<string> {
+  const schemas = await registerSchemas(store);
+  return store.put(schemas.rawOutput, { text: rawOutput });
+}

packages/workflow-agent-claude-code/src/types.ts

@@ -0,0 +1,19 @@
+export type ClaudeCodeResultSubtype = "success" | "error_max_turns" | "error_budget";
+
+export type ClaudeCodeParsedResult = {
+  type: string;
+  subtype: ClaudeCodeResultSubtype;
+  result: string;
+  sessionId: string;
+  numTurns: number;
+  totalCostUsd: number;
+  durationMs: number;
+};
+
+export type ClaudeCodeDetailPayload = {
+  sessionId: string;
+  numTurns: number;
+  totalCostUsd: number;
+  durationMs: number;
+  subtype: string;
+};

packages/workflow-agent-claude-code/tsconfig.json

@@ -0,0 +1,6 @@
+{
+  "extends": "../../tsconfig.json",
+  "compilerOptions": { "rootDir": "src", "outDir": "dist" },
+  "include": ["src"],
+  "references": [{ "path": "../workflow-agent-kit" }]
+}

packages/workflow-agent-hermes/src/hermes.ts

@@ -1,4 +1,5 @@
 import { spawn } from "node:child_process";
+import type { Store } from "@uncaged/json-cas";
 
 import {
   type AgentContext,
@@ -10,7 +11,6 @@ import {
 import {
   loadHermesSession,
   parseSessionIdFromStdout,
-  storeHermesRawOutput,
   storeHermesSessionDetail,
 } from "./session-detail.js";
 
@@ -52,17 +52,8 @@ export function buildHermesPrompt(ctx: AgentContext): string {
   return parts.join("\n");
 }
 
-function spawnHermesChat(prompt: string): Promise<{ stdout: string; stderr: string }> {
+function spawnHermes(args: string[]): Promise<{ stdout: string; stderr: string }> {
   return new Promise((resolve, reject) => {
-    const args = [
-      "chat",
-      "-q",
-      prompt,
-      "--yolo",
-      "--max-turns",
-      String(HERMES_MAX_TURNS),
-      "--quiet",
-    ];
     const child = spawn(HERMES_COMMAND, args, {
       env: process.env,
       shell: false,
@@ -94,23 +85,73 @@ function spawnHermesChat(prompt: string): Promise<{ stdout: string; stderr: stri
   });
 }
 
+function spawnHermesChat(prompt: string): Promise<{ stdout: string; stderr: string }> {
+  return spawnHermes([
+    "chat",
+    "-q",
+    prompt,
+    "--yolo",
+    "--max-turns",
+    String(HERMES_MAX_TURNS),
+    "--quiet",
+  ]);
+}
+
+function spawnHermesResume(
+  sessionId: string,
+  message: string,
+): Promise<{ stdout: string; stderr: string }> {
+  return spawnHermes([
+    "chat",
+    "--resume",
+    sessionId,
+    "-q",
+    message,
+    "--yolo",
+    "--max-turns",
+    String(HERMES_MAX_TURNS),
+    "--quiet",
+  ]);
+}
+
+function parseSessionId(stdout: string, stderr: string): string {
+  const sessionId = parseSessionIdFromStdout(stderr) ?? parseSessionIdFromStdout(stdout);
+  if (sessionId === null) {
+    throw new Error(
+      "Failed to parse session_id from hermes output.\n" +
+        `stderr (first 200 chars): ${stderr.slice(0, 200)}\n` +
+        `stdout (first 200 chars): ${stdout.slice(0, 200)}`,
+    );
+  }
+  return sessionId;
+}
+
+async function buildResultFromSession(sessionId: string, store: Store): Promise<AgentRunResult> {
+  const session = await loadHermesSession(sessionId);
+  if (session === null) {
+    throw new Error(`Failed to load hermes session file for session_id: ${sessionId}`);
+  }
+  const { detailHash, output } = await storeHermesSessionDetail(store, session);
+  return { output, detailHash, sessionId };
+}
+
 async function runHermes(ctx: AgentContext): Promise<AgentRunResult> {
   const fullPrompt = buildHermesPrompt(ctx);
   const { stdout, stderr } = await spawnHermesChat(fullPrompt);
-  const { store } = ctx;
+  const sessionId = parseSessionId(stdout, stderr);
+  return buildResultFromSession(sessionId, ctx.store);
+}
 
-  // --quiet mode: session_id may be on stdout or stderr
-  const sessionId = parseSessionIdFromStdout(stderr) ?? parseSessionIdFromStdout(stdout);
-  if (sessionId !== null) {
-    const session = await loadHermesSession(sessionId);
-    if (session !== null) {
-      const { detailHash, output } = await storeHermesSessionDetail(store, session);
-      return { output, detailHash };
-    }
-  }
-
-  const detailHash = await storeHermesRawOutput(store, stdout);
-  return { output: stdout, detailHash };
+async function continueHermes(
+  sessionId: string,
+  message: string,
+  store: Store,
+): Promise<AgentRunResult> {
+  const { stdout, stderr } = await spawnHermesResume(sessionId, message);
+  // Resume may return a new session_id
+  const newSessionId = parseSessionIdFromStdout(stderr) ?? parseSessionIdFromStdout(stdout);
+  const resolvedId = newSessionId ?? sessionId;
+  return buildResultFromSession(resolvedId, store);
 }
 
 /** Agent CLI factory: parses argv, runs Hermes, extracts output, writes StepNode. */
@@ -118,5 +159,6 @@ export function createHermesAgent(): () => Promise<void> {
   return createAgent({
     name: "hermes",
     run: runHermes,
+    continue: continueHermes,
   });
 }

packages/workflow-agent-kit/__tests__/build-output-format-instruction.test.ts

@@ -2,13 +2,32 @@ import { describe, expect, test } from "vitest";
 
 import { buildOutputFormatInstruction } from "../src/build-output-format-instruction.js";
 
+const PLANNER_SCHEMA = {
+  type: "object",
+  properties: {
+    status: { type: "string", enum: ["ready", "insufficient_info"] },
+    plan: { type: "string" },
+  },
+  required: ["status"],
+  additionalProperties: false,
+};
+
+const REVIEWER_SCHEMA = {
+  type: "object",
+  properties: {
+    approved: { type: "boolean" },
+  },
+  required: ["approved"],
+  additionalProperties: false,
+};
+
 describe("buildOutputFormatInstruction", () => {
   test("always includes the frontmatter example block", () => {
     const result = buildOutputFormatInstruction({});
     expect(result).toContain("---");
-    expect(result).toContain("status: done");
-    expect(result).toContain("confidence:");
-    expect(result).toContain("scope: role");
+    expect(result).not.toContain("status: done");
+    expect(result).not.toContain("confidence:");
+    expect(result).not.toContain("scope: role");
   });
 
   test("always marks frontmatter as the primary deliverable", () => {
@@ -16,17 +35,36 @@ describe("buildOutputFormatInstruction", () => {
     expect(result).toContain("primary deliverable");
   });
 
-  test("lists fields from a flat object schema", () => {
+  test("generates planner-specific YAML example from schema", () => {
+    const result = buildOutputFormatInstruction(PLANNER_SCHEMA);
+    expect(result).toContain("status: ready  # required | ready | insufficient_info");
+    expect(result).toContain("plan: <string>");
+    expect(result).not.toContain("status: done");
+    expect(result).not.toContain("confidence:");
+    expect(result).not.toContain("artifacts:");
+  });
+
+  test("generates reviewer-specific YAML example from schema", () => {
+    const result = buildOutputFormatInstruction(REVIEWER_SCHEMA);
+    expect(result).toContain("approved: true  # required | true | false");
+    expect(result).not.toContain("status:");
+  });
+
+  test("lists fields from a flat object schema with required marker", () => {
     const schema = {
       type: "object",
       properties: {
         status: { type: "string" },
         confidence: { type: "number" },
       },
+      required: ["status"],
     };
     const result = buildOutputFormatInstruction(schema);
-    expect(result).toContain("`status`");
+    expect(result).toContain("`status` (required)");
     expect(result).toContain("`confidence`");
+    expect(result).not.toContain("`confidence` (required)");
+    expect(result).toContain("status: <string>  # required");
+    expect(result).toContain("confidence: <number>");
   });
 
   test("lists union of fields from an anyOf schema", () => {
@@ -45,6 +83,8 @@ describe("buildOutputFormatInstruction", () => {
     const result = buildOutputFormatInstruction(schema);
     expect(result).toContain("`alpha`");
     expect(result).toContain("`beta`");
+    expect(result).toContain("alpha: <string>");
+    expect(result).toContain("beta: <number>");
   });
 
   test("lists union of fields from a oneOf schema", () => {
@@ -63,6 +103,8 @@ describe("buildOutputFormatInstruction", () => {
     const result = buildOutputFormatInstruction(schema);
     expect(result).toContain("`foo`");
     expect(result).toContain("`bar`");
+    expect(result).toContain("foo: <string>");
+    expect(result).toContain("bar: true  # true | false");
   });
 
   test("falls back gracefully for a non-object schema with no properties", () => {
@@ -80,6 +122,23 @@ describe("buildOutputFormatInstruction", () => {
     const result = buildOutputFormatInstruction(schema);
     const matches = [...result.matchAll(/`shared`/g)];
     expect(matches.length).toBe(1);
+    expect(result).toContain("shared: <string>");
+  });
+
+  test("marks required when any union variant requires the field", () => {
+    const schema = {
+      anyOf: [
+        {
+          type: "object",
+          properties: { shared: { type: "string" } },
+          required: ["shared"],
+        },
+        { type: "object", properties: { shared: { type: "number" } } },
+      ],
+    };
+    const result = buildOutputFormatInstruction(schema);
+    expect(result).toContain("`shared` (required)");
+    expect(result).toContain("shared: <string>  # required");
   });
 
   test("includes focus reminder about role scope", () => {

packages/workflow-agent-kit/__tests__/frontmatter-fast-path.test.ts

@@ -29,6 +29,27 @@ const STRICT_SCHEMA = {
   additionalProperties: false,
 };
 
+/** Role-specific schema (reviewer) — only approved, no standard agent fields. */
+const REVIEWER_SCHEMA = {
+  type: "object",
+  properties: {
+    approved: { type: "boolean" },
+  },
+  required: ["approved"],
+  additionalProperties: false,
+};
+
+/** Role-specific schema (planner) — custom status enum + plan hash. */
+const PLANNER_SCHEMA = {
+  type: "object",
+  properties: {
+    status: { type: "string", enum: ["ready", "insufficient_info"] },
+    plan: { type: "string" },
+  },
+  required: ["status"],
+  additionalProperties: false,
+};
+
 async function makeStoreWithSchema(schema: Record<string, unknown>) {
   const store = createMemoryStore();
   const schemaHash = await putSchema(store, schema);
@@ -134,3 +155,48 @@ describe("tryFrontmatterFastPath — fallback: schema mismatch", () => {
     expect(result).toBeNull();
   });
 });
+
+// ── Role-specific schema fields ───────────────────────────────────────────────
+
+describe("tryFrontmatterFastPath — role-specific fields", () => {
+  test("extracts approved only for reviewer schema (no extra standard fields)", async () => {
+    const { store, schemaHash } = await makeStoreWithSchema(REVIEWER_SCHEMA);
+
+    const raw = "---\napproved: true\n---\n\nReview passed.";
+
+    const result = await tryFrontmatterFastPath(raw, schemaHash, store);
+    expect(result).not.toBeNull();
+
+    const node = store.get(result!.outputHash);
+    expect(node).not.toBeNull();
+    const payload = node!.payload as Record<string, unknown>;
+    expect(payload).toEqual({ approved: true });
+    expect(payload.status).toBeUndefined();
+    expect(payload.scope).toBeUndefined();
+  });
+
+  test("extracts plan and role-specific status for planner schema", async () => {
+    const { store, schemaHash } = await makeStoreWithSchema(PLANNER_SCHEMA);
+
+    const raw = "---\nstatus: ready\nplan: 01HASHPLANNER0001\n---\n\nSpec summary.";
+
+    const result = await tryFrontmatterFastPath(raw, schemaHash, store);
+    expect(result).not.toBeNull();
+
+    const node = store.get(result!.outputHash);
+    expect(node).not.toBeNull();
+    const payload = node!.payload as Record<string, unknown>;
+    expect(payload.status).toBe("ready");
+    expect(payload.plan).toBe("01HASHPLANNER0001");
+    expect(payload.scope).toBeUndefined();
+  });
+
+  test("returns null when required role-specific field is missing", async () => {
+    const { store, schemaHash } = await makeStoreWithSchema(REVIEWER_SCHEMA);
+
+    const raw = "---\nstatus: done\nscope: role\n---\n\nBody.";
+
+    const result = await tryFrontmatterFastPath(raw, schemaHash, store);
+    expect(result).toBeNull();
+  });
+});

packages/workflow-agent-kit/src/build-output-format-instruction.ts

@@ -1,5 +1,11 @@
 import type { JSONSchema } from "@uncaged/json-cas";
 
+type SchemaProperty = {
+  name: string;
+  schema: JSONSchema;
+  required: boolean;
+};
+
 /**
  * Extract top-level property names from a JSON Schema object.
  *
@@ -9,9 +15,44 @@ import type { JSONSchema } from "@uncaged/json-cas";
  *
  * Returns an empty array for schemas with no inspectable property definitions.
  */
-function extractSchemaFields(schema: JSONSchema): string[] {
+export function extractSchemaFields(schema: JSONSchema): string[] {
+  return extractSchemaProperties(schema).map((p) => p.name);
+}
+
+function extractSchemaProperties(schema: JSONSchema): SchemaProperty[] {
+  const objectSchemas = collectObjectSchemas(schema);
+  if (objectSchemas.length === 0) {
+    return [];
+  }
+
+  const byName = new Map<string, SchemaProperty>();
+
+  for (const objectSchema of objectSchemas) {
+    const requiredSet = new Set(
+      Array.isArray(objectSchema.required) ? (objectSchema.required as string[]) : [],
+    );
+    const properties = objectSchema.properties as Record<string, JSONSchema> | null | undefined;
+    if (typeof properties !== "object" || properties === null) {
+      continue;
+    }
+
+    for (const [name, propSchema] of Object.entries(properties)) {
+      const required = requiredSet.has(name);
+      const existing = byName.get(name);
+      if (existing === undefined) {
+        byName.set(name, { name, schema: propSchema, required });
+      } else if (required) {
+        byName.set(name, { ...existing, required: true });
+      }
+    }
+  }
+
+  return [...byName.values()];
+}
+
+function collectObjectSchemas(schema: JSONSchema): JSONSchema[] {
   if (typeof schema.properties === "object" && schema.properties !== null) {
-    return Object.keys(schema.properties as Record<string, unknown>);
+    return [schema];
   }
 
   const unionKey = Array.isArray(schema.anyOf)
@@ -20,18 +61,109 @@ function extractSchemaFields(schema: JSONSchema): string[] {
       ? "oneOf"
       : null;
 
-  if (unionKey !== null) {
-    const variants = schema[unionKey] as JSONSchema[];
-    const fieldSet = new Set<string>();
-    for (const variant of variants) {
-      for (const field of extractSchemaFields(variant)) {
-        fieldSet.add(field);
-      }
-    }
-    return [...fieldSet];
+  if (unionKey === null) {
+    return [];
   }
 
-  return [];
+  const variants = schema[unionKey] as JSONSchema[];
+  const result: JSONSchema[] = [];
+  for (const variant of variants) {
+    result.push(...collectObjectSchemas(variant));
+  }
+  return result;
+}
+
+function resolvePropertySchema(prop: JSONSchema): JSONSchema {
+  if (Array.isArray(prop.enum) && prop.enum.length > 0) {
+    return prop;
+  }
+
+  const unionKey = Array.isArray(prop.anyOf) ? "anyOf" : Array.isArray(prop.oneOf) ? "oneOf" : null;
+
+  if (unionKey !== null) {
+    const variants = prop[unionKey] as JSONSchema[];
+    const nonNull = variants.filter((v) => v.type !== "null");
+    if (nonNull.length === 1) {
+      return nonNull[0];
+    }
+  }
+
+  return prop;
+}
+
+function formatYamlScalar(value: unknown): string {
+  if (typeof value === "boolean") {
+    return String(value);
+  }
+  if (typeof value === "number") {
+    return String(value);
+  }
+  return String(value);
+}
+
+function buildPropertyComment(parts: string[]): string {
+  const filtered = parts.filter((p) => p.length > 0);
+  return filtered.length > 0 ? `  # ${filtered.join(" | ")}` : "";
+}
+
+function buildPropertyExampleLine(prop: SchemaProperty): string {
+  const resolved = resolvePropertySchema(prop.schema);
+  const commentParts: string[] = [];
+  if (prop.required) {
+    commentParts.push("required");
+  }
+
+  if (Array.isArray(resolved.enum) && resolved.enum.length > 0) {
+    const enumValues = resolved.enum.map((v) => String(v));
+    commentParts.push(...enumValues);
+    const first = resolved.enum[0];
+    return `${prop.name}: ${formatYamlScalar(first)}${buildPropertyComment(commentParts)}`;
+  }
+
+  if (resolved.type === "boolean") {
+    commentParts.push("true", "false");
+    return `${prop.name}: true${buildPropertyComment(commentParts)}`;
+  }
+
+  if (resolved.type === "string") {
+    return `${prop.name}: <string>${buildPropertyComment(commentParts)}`;
+  }
+
+  if (resolved.type === "number" || resolved.type === "integer") {
+    return `${prop.name}: <number>${buildPropertyComment(commentParts)}`;
+  }
+
+  if (resolved.type === "array") {
+    return `${prop.name}:\n  - <item>${buildPropertyComment(commentParts)}`;
+  }
+
+  if (resolved.type === "object") {
+    return `${prop.name}: <object>${buildPropertyComment(commentParts)}`;
+  }
+
+  return `${prop.name}: <value>${buildPropertyComment(commentParts)}`;
+}
+
+function buildYamlExampleBlock(properties: SchemaProperty[]): string {
+  if (properties.length === 0) {
+    return "---\n\n... your markdown work here ...";
+  }
+
+  const lines = properties.map((p) => buildPropertyExampleLine(p));
+  return `---\n${lines.join("\n")}\n---\n\n... your markdown work here ...`;
+}
+
+function buildFieldList(properties: SchemaProperty[]): string {
+  if (properties.length === 0) {
+    return "  (schema fields will be extracted automatically)";
+  }
+
+  return properties
+    .map((p) => {
+      const suffix = p.required ? " (required)" : "";
+      return `  - \`${p.name}\`${suffix}`;
+    })
+    .join("\n");
 }
 
 /**
@@ -42,28 +174,16 @@ function extractSchemaFields(schema: JSONSchema): string[] {
  * system prompt so the deliverable format is the first thing the agent sees.
  */
 export function buildOutputFormatInstruction(schema: JSONSchema): string {
-  const fields = extractSchemaFields(schema);
-
-  const fieldList =
-    fields.length > 0
-      ? fields.map((f) => `  - \`${f}\``).join("\n")
-      : "  (schema fields will be extracted automatically)";
+  const properties = extractSchemaProperties(schema);
+  const yamlExample = buildYamlExampleBlock(properties);
+  const fieldList = buildFieldList(properties);
 
   return `## Deliverable Format
 
 Your response MUST begin with a YAML frontmatter block followed by your markdown work:
 
 \`\`\`
----
-status: done          # done | needs_input | in_progress | failed
-next: <role-name>     # suggested next role, or omit
-confidence: 0.9       # 0.0–1.0, your self-assessed confidence
-artifacts:            # list of file paths or CAS hashes you produced
-  - path/to/file.ts
-scope: role           # role | thread
----
-
-... your markdown work here ...
+${yamlExample}
 \`\`\`
 
 The frontmatter is the **primary deliverable** — the engine reads it directly.

packages/workflow-agent-kit/src/frontmatter.ts

@@ -1,13 +1,139 @@
 import type { Store } from "@uncaged/json-cas";
-import { validate } from "@uncaged/json-cas";
+import { getSchema, validate } from "@uncaged/json-cas";
 import type { CasRef } from "@uncaged/workflow-protocol";
-import { parseFrontmatterMarkdown, validateFrontmatter } from "@uncaged/workflow-util";
+import {
+  type AgentFrontmatter,
+  createLogger,
+  parseFrontmatterMarkdown,
+  validateFrontmatter,
+} from "@uncaged/workflow-util";
+import { parse as parseYaml } from "yaml";
+
+import { extractSchemaFields } from "./build-output-format-instruction.js";
+
+const log = createLogger({ sink: { kind: "stderr" } });
+
+const STANDARD_KEYS = ["status", "next", "confidence", "artifacts", "scope"] as const;
+
+type StandardKey = (typeof STANDARD_KEYS)[number];
 
 export type FrontmatterFastPathResult = {
   body: string;
   outputHash: CasRef;
 };
 
+function extractYamlBlock(raw: string): string | null {
+  const fence = "---";
+  if (!raw.startsWith(fence)) {
+    return null;
+  }
+
+  const rest = raw.slice(fence.length);
+  if (rest.length > 0 && rest[0] !== "\n" && rest[0] !== "\r") {
+    return null;
+  }
+
+  const afterOpen = rest.startsWith("\n") ? rest.slice(1) : rest;
+  const closeIndex = afterOpen.indexOf(`\n${fence}`);
+  if (closeIndex === -1) {
+    return null;
+  }
+
+  return afterOpen.slice(0, closeIndex);
+}
+
+function parseRawFrontmatterFields(raw: string): Record<string, unknown> {
+  const yamlText = extractYamlBlock(raw);
+  if (yamlText === null) {
+    return {};
+  }
+
+  try {
+    const parsed = parseYaml(yamlText);
+    if (typeof parsed !== "object" || parsed === null || Array.isArray(parsed)) {
+      return {};
+    }
+    return parsed as Record<string, unknown>;
+  } catch {
+    return {};
+  }
+}
+
+function defaultCandidate(frontmatter: AgentFrontmatter): Record<string, unknown> {
+  return {
+    status: frontmatter.status,
+    next: frontmatter.next,
+    confidence: frontmatter.confidence,
+    artifacts: [...frontmatter.artifacts],
+    scope: frontmatter.scope,
+  };
+}
+
+function pickStandardField(frontmatter: AgentFrontmatter, key: StandardKey): unknown {
+  switch (key) {
+    case "status":
+      return frontmatter.status;
+    case "next":
+      return frontmatter.next;
+    case "confidence":
+      return frontmatter.confidence;
+    case "artifacts":
+      return [...frontmatter.artifacts];
+    case "scope":
+      return frontmatter.scope;
+  }
+}
+
+function isStandardKey(key: string): key is StandardKey {
+  return (STANDARD_KEYS as readonly string[]).includes(key);
+}
+
+function pickFieldValue(
+  field: string,
+  frontmatter: AgentFrontmatter,
+  rawFields: Record<string, unknown>,
+): unknown | undefined {
+  if (!isStandardKey(field)) {
+    return Object.hasOwn(rawFields, field) ? rawFields[field] : undefined;
+  }
+
+  const coerced = pickStandardField(frontmatter, field);
+  if (field === "artifacts" || field === "scope") {
+    return coerced;
+  }
+  if (coerced !== null) {
+    return coerced;
+  }
+  return Object.hasOwn(rawFields, field) ? rawFields[field] : coerced;
+}
+
+/**
+ * Build a CAS candidate object from schema property keys and parsed frontmatter.
+ *
+ * When the schema has no inspectable properties, falls back to the five standard
+ * agent frontmatter fields for backward compatibility.
+ */
+function buildCandidate(
+  frontmatter: AgentFrontmatter,
+  rawFields: Record<string, unknown>,
+  schemaFields: string[],
+): Record<string, unknown> {
+  if (schemaFields.length === 0) {
+    return defaultCandidate(frontmatter);
+  }
+
+  const candidate: Record<string, unknown> = {};
+
+  for (const field of schemaFields) {
+    const value = pickFieldValue(field, frontmatter, rawFields);
+    if (value !== undefined) {
+      candidate[field] = value;
+    }
+  }
+
+  return candidate;
+}
+
 /**
  * Try to satisfy `outputSchema` from frontmatter fields alone.
  *
@@ -32,16 +158,22 @@ export async function tryFrontmatterFastPath(
 
   const validationErrors = validateFrontmatter(frontmatter);
   if (validationErrors.length > 0) {
+    log(
+      "9GNPS4WY",
+      `frontmatter validation errors: ${validationErrors.map((e) => e.message).join("; ")}`,
+    );
     return null;
   }
 
-  const candidate: Record<string, unknown> = {
-    status: frontmatter.status,
-    next: frontmatter.next,
-    confidence: frontmatter.confidence,
-    artifacts: [...frontmatter.artifacts],
-    scope: frontmatter.scope,
-  };
+  const schema = getSchema(store, outputSchema);
+  if (schema === null) {
+    log("8FHMR2QX", `output schema not found in CAS: ${outputSchema}`);
+    return null;
+  }
+
+  const schemaFields = extractSchemaFields(schema);
+  const rawFields = parseRawFrontmatterFields(raw);
+  const candidate = buildCandidate(frontmatter, rawFields, schemaFields);
 
   let outputHash: CasRef;
   let node: ReturnType<Store["get"]>;
@@ -50,10 +182,12 @@ export async function tryFrontmatterFastPath(
     outputHash = await store.put(outputSchema, candidate);
     node = store.get(outputHash);
   } catch {
+    log("2KMQT7NR", "failed to store frontmatter candidate in CAS");
     return null;
   }
 
   if (node === null || !validate(store, node)) {
+    log("2KMQT7NR", "stored frontmatter candidate failed schema validation");
     return null;
   }
 

packages/workflow-agent-kit/src/index.ts

@@ -12,4 +12,10 @@ export type { FrontmatterFastPathResult } from "./frontmatter.js";
 export { tryFrontmatterFastPath } from "./frontmatter.js";
 export { createAgent } from "./run.js";
 export { getConfigPath, getEnvPath, loadWorkflowConfig } from "./storage.js";
-export type { AgentContext, AgentOptions, AgentRunFn, AgentRunResult } from "./types.js";
+export type {
+  AgentContext,
+  AgentContinueFn,
+  AgentOptions,
+  AgentRunFn,
+  AgentRunResult,
+} from "./types.js";

packages/workflow-agent-kit/src/run.ts

@@ -3,11 +3,12 @@ import type { CasRef, StepNodePayload, ThreadId } from "@uncaged/workflow-protoc
 import { config as loadDotenv } from "dotenv";
 import { buildOutputFormatInstruction } from "./build-output-format-instruction.js";
 import { buildContextWithMeta } from "./context.js";
-import { extract } from "./extract.js";
 import { tryFrontmatterFastPath } from "./frontmatter.js";
 import type { AgentStore } from "./storage.js";
-import { getEnvPath, loadWorkflowConfig, resolveStorageRoot } from "./storage.js";
-import type { AgentContext, AgentOptions, AgentRunResult } from "./types.js";
+import { getEnvPath, resolveStorageRoot } from "./storage.js";
+import type { AgentOptions } from "./types.js";
+
+const MAX_FRONTMATTER_RETRIES = 2;
 
 function fail(message: string): never {
   process.stderr.write(`${message}\n`);
@@ -66,31 +67,16 @@ async function writeStepNode(options: {
   return hash;
 }
 
-async function runAgent(options: AgentOptions, ctx: AgentContext): Promise<AgentRunResult> {
-  return runWithMessage("agent run failed", () => options.run(ctx));
-}
-
-async function extractOutput(
+async function tryExtractOutput(
   rawOutput: string,
   outputSchema: CasRef,
-  storageRoot: string,
   ctx: Awaited<ReturnType<typeof buildContextWithMeta>>,
-): Promise<CasRef> {
-  const fastPath = await runWithMessage("frontmatter fast path", () =>
-    tryFrontmatterFastPath(rawOutput, outputSchema, ctx.meta.store),
-  ).catch(() => null);
-
+): Promise<CasRef | null> {
+  const fastPath = await tryFrontmatterFastPath(rawOutput, outputSchema, ctx.meta.store);
   if (fastPath !== null) {
     return fastPath.outputHash;
   }
-
-  const config = await runWithMessage("failed to load config", () =>
-    loadWorkflowConfig(storageRoot),
-  );
-  const extracted = await runWithMessage("extract failed", () =>
-    extract(rawOutput, outputSchema, config),
-  );
-  return extracted.hash;
+  return null;
 }
 
 async function persistStep(options: {
@@ -112,11 +98,6 @@ async function persistStep(options: {
   });
 }
 
-/**
- * Create an agent CLI entrypoint.
- * Parses argv (`<thread-id> <role>`), runs the agent, extracts structured output,
- * writes StepNode to CAS, and prints the new node hash to stdout.
- */
 export function createAgent(options: AgentOptions): () => Promise<void> {
   return async function main(): Promise<void> {
     const { threadId, role } = parseArgv(process.argv);
@@ -135,13 +116,31 @@ export function createAgent(options: AgentOptions): () => Promise<void> {
       ctx.outputFormatInstruction = buildOutputFormatInstruction(frontmatterSchema);
     }
 
-    const agentResult = await runAgent(options, ctx);
-    const outputHash = await extractOutput(
-      agentResult.output,
-      roleDef.frontmatter,
-      storageRoot,
-      ctx,
-    );
+    let agentResult = await runWithMessage("agent run failed", () => options.run(ctx));
+
+    // Try to extract frontmatter; retry via continue if it fails
+    let outputHash = await tryExtractOutput(agentResult.output, roleDef.frontmatter, ctx);
+
+    for (let retry = 0; retry < MAX_FRONTMATTER_RETRIES && outputHash === null; retry++) {
+      const correctionMessage =
+        "Your previous response did not contain valid YAML frontmatter matching the role schema.\n" +
+        "You MUST begin your response with a YAML frontmatter block (--- delimited).\n" +
+        "Please output ONLY the corrected frontmatter block followed by your work.";
+
+      agentResult = await runWithMessage("agent continue failed", () =>
+        options.continue(agentResult.sessionId, correctionMessage, ctx.meta.store),
+      );
+      outputHash = await tryExtractOutput(agentResult.output, roleDef.frontmatter, ctx);
+    }
+
+    if (outputHash === null) {
+      fail(
+        "Agent output does not contain valid YAML frontmatter matching the role schema " +
+          `after ${MAX_FRONTMATTER_RETRIES} retries.\n` +
+          `Raw output (first 500 chars): ${agentResult.output.slice(0, 500)}`,
+      );
+    }
+
     const stepHash = await persistStep({
       ctx,
       outputHash,

packages/workflow-agent-kit/src/types.ts

@@ -17,11 +17,19 @@ export type AgentContext = ModeratorContext & {
 export type AgentRunResult = {
   output: string;
   detailHash: string;
+  sessionId: string;
 };
 
+export type AgentContinueFn = (
+  sessionId: string,
+  message: string,
+  store: AgentContext["store"],
+) => Promise<AgentRunResult>;
+
 export type AgentRunFn = (ctx: AgentContext) => Promise<AgentRunResult>;
 
 export type AgentOptions = {
   name: string;
   run: AgentRunFn;
+  continue: AgentContinueFn;
 };

packages/workflow-util/src/cli-reference.ts

@@ -46,6 +46,8 @@ uwf cas get <hash>                # read a CAS node (type + payload)
             [--timestamp]         # include timestamp in output
 uwf cas put <type-hash> <data>    # store a node, print its hash
                                   # <data>: JSON file path or inline JSON string
+uwf cas put-text <text>           # store a plain text string, print its hash
+                                  # shortcut for put with the built-in text schema
 uwf cas has <hash>                # check if a hash exists
 uwf cas refs <hash>               # list direct CAS references from a node
 uwf cas walk <hash>               # recursive traversal from a node