fix: generate frontmatter instruction dynamically from role schema

Replace hardcoded 5-field example with schema-driven generation.
Now shows actual enum values, types, and required markers for
each role's frontmatter schema.

Fixes #389

小橘 <xiaoju@shazhou.work>

.workflows/solve-issue.yaml

@@ -0,0 +1,167 @@
+name: "solve-issue"
+description: "TDD-driven issue resolution for small, focused changes. Loop protection relies on engine maxRounds."
+roles:
+  planner:
+    description: "Analyzes issue and outputs a TDD test spec"
+    goal: "You are a planning agent. You analyze Gitea issues and produce a TDD test specification that downstream roles will implement and verify."
+    capabilities:
+      - issue-analysis
+      - planning
+    procedure: |
+      On first run (no previous steps):
+      1. Read the issue and all comments from Gitea using `tea issues <number> -r <owner/repo>`
+      2. Read CLAUDE.md (or equivalent project conventions file) to understand coding standards
+      3. Assess whether the issue has enough information to produce a test spec
+      4. If insufficient info: comment on the issue via `echo "..." | tea comment <number> -r <owner/repo>` (skip if you already commented), then output status=insufficient_info and terminate
+      5. If sufficient: produce a detailed TDD test spec in markdown covering all scenarios
+
+      On subsequent runs (bounced back by tester with fix_spec):
+      1. Read the tester's output from the previous step to understand what's wrong with the spec
+      2. Revise the test spec accordingly
+
+      After producing the test spec:
+      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
+      properties:
+        status:
+          type: string
+          enum: [ready, insufficient_info]
+        plan:
+          type: string
+      required: [status]
+  developer:
+    description: "TDD implementation per test spec"
+    goal: "You are a developer agent. You implement code changes following TDD — write tests first, then implementation."
+    capabilities:
+      - coding
+    procedure: |
+      1. Read the test spec from CAS: `uwf cas get <plan hash>` (find the hash from the latest planner step's meta.plan)
+      2. If bounced back from reviewer or tester: read the previous role's output to understand what needs fixing
+      3. Write tests first based on the spec
+      4. Implement the code to make tests pass
+      5. Ensure `bun run build` passes with no errors
+      6. Run `bun test` to verify all tests pass
+    output: "List all files changed and provide a summary. Frontmatter must include: status (done or failed)."
+    frontmatter:
+      type: object
+      properties:
+        status:
+          type: string
+          enum: [done, failed]
+      required: [status]
+  reviewer:
+    description: "Code standards compliance check"
+    goal: "You are a code reviewer. You verify code standards compliance — NOT functionality (that's the tester's job)."
+    capabilities:
+      - code-review
+      - static-analysis
+    procedure: |
+      Hard checks (must all pass):
+      1. `bun run build` — no build errors
+      2. `bunx biome check` — no lint violations
+      3. TypeScript strict mode — no type errors
+
+      Soft checks (review against CLAUDE.md conventions):
+      - Functional-first: `function` + `type`, not `class` + `interface`
+      - No optional properties (`?:`) — use `T | null`
+      - Naming conventions (kebab-case files, PascalCase types, camelCase functions)
+      - Module boundary discipline (folder exports via index.ts)
+      - No `console.log` (use structured logger)
+      - No dynamic imports in production code
+
+      Only review standards compliance. Do NOT test functionality.
+      If rejecting, you MUST explain the specific reason in your output.
+    output: "Explain your decision with specific file/line references. Frontmatter must include: approved (true or false)."
+    frontmatter:
+      type: object
+      properties:
+        approved:
+          type: boolean
+      required: [approved]
+  tester:
+    description: "Functional correctness verification"
+    goal: "You are a tester agent. You verify that the implementation correctly satisfies every scenario in the test spec."
+    capabilities:
+      - testing
+    procedure: |
+      1. Run `bun test` for automated test verification
+      2. Read the test spec from CAS: `uwf cas get <plan hash>` (find the hash from the latest planner step's meta.plan)
+      3. Verify each scenario in the spec is covered and passing
+      4. Determine outcome:
+         - passed: all scenarios verified, tests pass
+         - fix_code: tests fail or implementation doesn't match spec → send back to developer
+         - fix_spec: the spec itself is wrong or incomplete → send back to planner
+    output: "Report test results per scenario. Frontmatter must include: status (passed, fix_code, or fix_spec)."
+    frontmatter:
+      type: object
+      properties:
+        status:
+          type: string
+          enum: [passed, fix_code, fix_spec]
+      required: [status]
+  committer:
+    description: "Commits and creates PR"
+    goal: "You are a committer agent. You create a clean commit and push a PR linking the original issue."
+    capabilities: []
+    procedure: |
+      Note: You inherit the developer's worktree and branch. Do NOT create a new branch.
+      1. Stage all changes: `git add -A`
+      2. Commit with a descriptive message referencing the issue: `git commit -m "type: description\n\nFixes #N"`
+      3. Push the branch: `git push -u origin <branch-name>`
+         - If push hook fails: capture the error log in your output, mark hook_failed
+      4. On push success: create a PR via `tea pr create --title "..." --description "..."`
+         - PR description must follow the project template: What / Why / Changes / Ref sections, with `Fixes #N` in Ref
+    output: "Include PR URL on success or error log on failure. Frontmatter must include: success (true or false)."
+    frontmatter:
+      type: object
+      properties:
+        success:
+          type: boolean
+      required: [success]
+conditions:
+  insufficientInfo:
+    description: "Planner determined there's not enough info to proceed"
+    expression: "$last('planner').status = 'insufficient_info'"
+  devFailed:
+    description: "Developer failed to implement"
+    expression: "$last('developer').status = 'failed'"
+  rejected:
+    description: "Reviewer rejected the implementation"
+    expression: "$last('reviewer').approved = false"
+  fixCode:
+    description: "Tester found code issues"
+    expression: "$last('tester').status = 'fix_code'"
+  fixSpec:
+    description: "Tester found spec issues"
+    expression: "$last('tester').status = 'fix_spec'"
+  hookFailed:
+    description: "Push hook failed"
+    expression: "$last('committer').success = false"
+graph:
+  $START:
+    - role: "planner"
+  planner:
+    - role: "$END"
+      condition: "insufficientInfo"
+    - role: "developer"
+  developer:
+    - role: "$END"
+      condition: "devFailed"
+    - role: "reviewer"
+  reviewer:
+    - role: "developer"
+      condition: "rejected"
+    - role: "tester"
+  tester:
+    - role: "developer"
+      condition: "fixCode"
+    - role: "planner"
+      condition: "fixSpec"
+    - role: "committer"
+  committer:
+    - role: "developer"
+      condition: "hookFailed"
+    - role: "$END"

examples/analyze-topic.yaml

@@ -19,7 +19,7 @@ roles:
     output: |
       Provide your analysis as markdown under the frontmatter.
       The frontmatter must include your structured findings.
-    meta:
+    frontmatter:
       type: object
       properties:
         thesis:

examples/solve-issue.yaml

@@ -9,7 +9,7 @@ roles:
       - planning
     procedure: "Analyze the issue and create a detailed, actionable implementation plan."
     output: "Output the plan summary and list of concrete steps."
-    meta:
+    frontmatter:
       type: object
       properties:
         plan:
@@ -28,7 +28,7 @@ roles:
       - testing
     procedure: "Implement the plan. Write code, tests, and ensure existing tests pass."
     output: "List all files changed and provide a summary of the implementation."
-    meta:
+    frontmatter:
       type: object
       properties:
         filesChanged:
@@ -46,7 +46,7 @@ roles:
       - static-analysis
     procedure: "Review the implementation against the plan. Check for bugs, edge cases, and style."
     output: "Approve or reject with detailed comments explaining your decision."
-    meta:
+    frontmatter:
       type: object
       properties:
         approved:
@@ -57,7 +57,7 @@ roles:
 conditions:
   notApproved:
     description: "Reviewer rejected the implementation"
-    expression: "steps[-1].output.approved = false"
+    expression: "$last('reviewer').approved = false"
 graph:
   $START:
     - role: "planner"

packages/cli-workflow/src/cli.ts

@@ -7,6 +7,7 @@ import {
   cmdCasGet,
   cmdCasHas,
   cmdCasPut,
+  cmdCasPutText,
   cmdCasRefs,
   cmdCasReindex,
   cmdCasSchemaGet,
@@ -295,6 +296,17 @@ 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/workflow.ts

@@ -2,7 +2,12 @@ import { readFile } from "node:fs/promises";
 
 import type { JSONSchema } from "@uncaged/json-cas";
 import { putSchema, validate } from "@uncaged/json-cas";
-import type { CasRef, RoleDefinition, WorkflowPayload } from "@uncaged/workflow-protocol";
+import type {
+  CasRef,
+  RoleDefinition,
+  Transition,
+  WorkflowPayload,
+} from "@uncaged/workflow-protocol";
 import { parse } from "yaml";
 
 import {
@@ -46,11 +51,28 @@ function isJsonSchema(value: unknown): value is JSONSchema {
   return typeof value === "object" && value !== null && !Array.isArray(value);
 }
 
-async function resolveMetaRef(uwf: UwfStore, roleName: string, meta: unknown): Promise<CasRef> {
-  if (!isJsonSchema(meta)) {
-    fail(`role "${roleName}": meta must be a JSON Schema object`);
+/** Normalize graph transitions: ensure condition is null (not undefined) for fallback entries. */
+function normalizeGraph(graph: Record<string, Transition[]>): Record<string, Transition[]> {
+  const result: Record<string, Transition[]> = {};
+  for (const [node, transitions] of Object.entries(graph)) {
+    result[node] = transitions.map((t) => ({
+      role: t.role,
+      condition: t.condition ?? null,
+    }));
   }
-  const schema: JSONSchema = meta.title === undefined ? { ...meta, title: roleName } : meta;
+  return result;
+}
+
+async function resolveFrontmatterRef(
+  uwf: UwfStore,
+  roleName: string,
+  frontmatter: unknown,
+): Promise<CasRef> {
+  if (!isJsonSchema(frontmatter)) {
+    fail(`role "${roleName}": frontmatter must be a JSON Schema object`);
+  }
+  const schema: JSONSchema =
+    frontmatter.title === undefined ? { ...frontmatter, title: roleName } : frontmatter;
   return putSchema(uwf.store, schema);
 }
 
@@ -60,14 +82,18 @@ export async function materializeWorkflowPayload(
 ): Promise<WorkflowPayload> {
   const roles: Record<string, RoleDefinition> = {};
   for (const [roleName, role] of Object.entries(raw.roles)) {
-    const meta = await resolveMetaRef(uwf, `${raw.name}.${roleName}`, role.meta);
+    const frontmatter = await resolveFrontmatterRef(
+      uwf,
+      `${raw.name}.${roleName}`,
+      role.frontmatter,
+    );
     roles[roleName] = {
       description: role.description,
       goal: role.goal,
       capabilities: role.capabilities,
       procedure: role.procedure,
       output: role.output,
-      meta,
+      frontmatter,
     };
   }
   return {
@@ -75,7 +101,7 @@ export async function materializeWorkflowPayload(
     description: raw.description,
     roles,
     conditions: raw.conditions,
-    graph: raw.graph,
+    graph: normalizeGraph(raw.graph),
   };
 }
 

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/cli-workflow/src/validate.ts

@@ -15,8 +15,8 @@ function isRoleDefinition(value: unknown): boolean {
   if (!isRecord(value)) {
     return false;
   }
-  const meta = value.meta;
-  const metaOk = isRecord(meta) && typeof meta.type === "string";
+  const frontmatter = value.frontmatter;
+  const frontmatterOk = isRecord(frontmatter) && typeof frontmatter.type === "string";
   const capabilities = value.capabilities;
   const capabilitiesOk =
     Array.isArray(capabilities) && capabilities.every((c) => typeof c === "string");
@@ -26,7 +26,7 @@ function isRoleDefinition(value: unknown): boolean {
     capabilitiesOk &&
     typeof value.procedure === "string" &&
     typeof value.output === "string" &&
-    metaOk
+    frontmatterOk
   );
 }
 
@@ -42,7 +42,10 @@ function isTransition(value: unknown): boolean {
     return false;
   }
   const condition = value.condition;
-  return typeof value.role === "string" && (condition === null || typeof condition === "string");
+  return (
+    typeof value.role === "string" &&
+    (condition === null || condition === undefined || typeof condition === "string")
+  );
 }
 
 function isStringRecord(value: unknown, itemCheck: (item: unknown) => boolean): boolean {

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);
@@ -130,13 +111,36 @@ export function createAgent(options: AgentOptions): () => Promise<void> {
       fail(`unknown role: ${role}`);
     }
 
-    const metaSchema = getSchema(ctx.meta.store, roleDef.meta);
-    if (metaSchema !== null) {
-      ctx.outputFormatInstruction = buildOutputFormatInstruction(metaSchema);
+    const frontmatterSchema = getSchema(ctx.meta.store, roleDef.frontmatter);
+    if (frontmatterSchema !== null) {
+      ctx.outputFormatInstruction = buildOutputFormatInstruction(frontmatterSchema);
+    }
+
+    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 agentResult = await runAgent(options, ctx);
-    const outputHash = await extractOutput(agentResult.output, roleDef.meta, storageRoot, ctx);
     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-moderator/__tests__/evaluate.test.ts

@@ -35,11 +35,11 @@ const solveIssueWorkflow: WorkflowPayload = {
   conditions: {
     needsClarification: {
       description: "Planner requests clarification from user",
-      expression: "$exists(steps[-1].output.needsClarification)",
+      expression: "$exists($last('planner').needsClarification)",
     },
-    notApproved: {
+    rejected: {
       description: "Reviewer rejected the implementation",
-      expression: "steps[-1].output.approved = false",
+      expression: "$last('reviewer').approved = false",
     },
   },
   graph: {
@@ -50,7 +50,7 @@ const solveIssueWorkflow: WorkflowPayload = {
     ],
     developer: [{ role: "reviewer", condition: null }],
     reviewer: [
-      { role: "developer", condition: "notApproved" },
+      { role: "developer", condition: "rejected" },
       { role: "$END", condition: null },
     ],
   },
@@ -72,7 +72,7 @@ describe("evaluate", () => {
     expect(result).toEqual({ ok: true, value: "planner" });
   });
 
-  test("condition match (notApproved → developer)", async () => {
+  test("condition match (rejected → developer)", async () => {
     const context = makeContext([
       {
         role: "reviewer",
@@ -126,4 +126,116 @@ describe("evaluate", () => {
     const result = await evaluate(solveIssueWorkflow, context);
     expect(result).toEqual({ ok: true, value: "developer" });
   });
+
+  test("$last returns most recent matching role's frontmatter", async () => {
+    const workflow: WorkflowPayload = {
+      ...solveIssueWorkflow,
+      conditions: {
+        devFailed: {
+          description: "Developer failed",
+          expression: "$last('developer').status = 'failed'",
+        },
+      },
+      graph: {
+        $START: [{ role: "developer", condition: null }],
+        developer: [
+          { role: "$END", condition: "devFailed" },
+          { role: "reviewer", condition: null },
+        ],
+      },
+    };
+    const context = makeContext([
+      {
+        role: "developer",
+        output: { status: "done" },
+        detail: "1VPBG9SM5E7WK",
+        agent: "uwf-hermes",
+      },
+      {
+        role: "reviewer",
+        output: { approved: false },
+        detail: "2MXBG6PN4A8JR",
+        agent: "uwf-hermes",
+      },
+      {
+        role: "developer",
+        output: { status: "failed" },
+        detail: "3QNTH7WK8D2PA",
+        agent: "uwf-hermes",
+      },
+    ]);
+    const result = await evaluate(workflow, context);
+    expect(result).toEqual({ ok: true, value: "$END" });
+  });
+
+  test("$first returns earliest matching role's frontmatter", async () => {
+    const workflow: WorkflowPayload = {
+      ...solveIssueWorkflow,
+      conditions: {
+        firstPlanReady: {
+          description: "First planner run was ready",
+          expression: "$first('planner').status = 'ready'",
+        },
+      },
+      graph: {
+        $START: [{ role: "planner", condition: null }],
+        planner: [
+          { role: "$END", condition: "firstPlanReady" },
+          { role: "developer", condition: null },
+        ],
+      },
+    };
+    const context = makeContext([
+      {
+        role: "planner",
+        output: { status: "ready", plan: "ABC123" },
+        detail: "7BQST3VW9F2MA",
+        agent: "uwf-hermes",
+      },
+      {
+        role: "developer",
+        output: { status: "done" },
+        detail: "1VPBG9SM5E7WK",
+        agent: "uwf-hermes",
+      },
+      {
+        role: "planner",
+        output: { status: "revised", plan: "DEF456" },
+        detail: "4RNMK6PX8B3WQ",
+        agent: "uwf-hermes",
+      },
+    ]);
+    const result = await evaluate(workflow, context);
+    expect(result).toEqual({ ok: true, value: "$END" });
+  });
+
+  test("$last returns undefined for unmatched role", async () => {
+    const workflow: WorkflowPayload = {
+      ...solveIssueWorkflow,
+      conditions: {
+        hasReviewer: {
+          description: "Reviewer has run",
+          expression: "$exists($last('reviewer'))",
+        },
+      },
+      graph: {
+        $START: [{ role: "planner", condition: null }],
+        planner: [
+          { role: "$END", condition: "hasReviewer" },
+          { role: "developer", condition: null },
+        ],
+      },
+    };
+    const context = makeContext([
+      {
+        role: "planner",
+        output: { status: "ready" },
+        detail: "7BQST3VW9F2MA",
+        agent: "uwf-hermes",
+      },
+    ]);
+    const result = await evaluate(workflow, context);
+    // no reviewer step → $exists returns false → fallback to developer
+    expect(result).toEqual({ ok: true, value: "developer" });
+  });
 });

packages/workflow-moderator/src/evaluate.ts

@@ -21,12 +21,44 @@ function isTruthy(value: unknown): boolean {
   return true;
 }
 
+function findByRole(
+  steps: ModeratorContext["steps"],
+  role: string,
+  direction: "first" | "last",
+): unknown {
+  if (direction === "last") {
+    for (let i = steps.length - 1; i >= 0; i--) {
+      if (steps[i].role === role) {
+        return steps[i].output;
+      }
+    }
+  } else {
+    for (const step of steps) {
+      if (step.role === role) {
+        return step.output;
+      }
+    }
+  }
+  return undefined;
+}
+
 async function evaluateJsonata(
   expression: string,
   context: ModeratorContext,
 ): Promise<Result<unknown, Error>> {
   try {
-    const result = await jsonata(expression).evaluate(context);
+    const expr = jsonata(expression);
+    expr.registerFunction(
+      "first",
+      (role: string) => findByRole(context.steps, role, "first"),
+      "<s:x>",
+    );
+    expr.registerFunction(
+      "last",
+      (role: string) => findByRole(context.steps, role, "last"),
+      "<s:x>",
+    );
+    const result = await expr.evaluate(context);
     return { ok: true, value: result };
   } catch (error) {
     return {

packages/workflow-protocol/src/schemas.ts

@@ -2,14 +2,14 @@ import type { JSONSchema } from "@uncaged/json-cas";
 
 const ROLE_DEFINITION: JSONSchema = {
   type: "object",
-  required: ["description", "goal", "capabilities", "procedure", "output", "meta"],
+  required: ["description", "goal", "capabilities", "procedure", "output", "frontmatter"],
   properties: {
     description: { type: "string" },
     goal: { type: "string" },
     capabilities: { type: "array", items: { type: "string" } },
     procedure: { type: "string" },
     output: { type: "string" },
-    meta: { type: "string", format: "cas_ref" },
+    frontmatter: { type: "string", format: "cas_ref" },
   },
   additionalProperties: false,
 };

packages/workflow-protocol/src/types.ts

@@ -22,7 +22,7 @@ export type RoleDefinition = {
   capabilities: string[];
   procedure: string;
   output: string;
-  meta: CasRef;
+  frontmatter: CasRef;
 };
 
 export type Transition = {

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