fix: revert output protocol changes from #385

Agent CLI outputs plain CAS hash (not JSON), engine parses plain hash.
StepOutput no longer carries sessionId — session info is already in CAS detail.
Keeps the valuable parts of #385: sessionId in AgentRunResult (process-internal),
continue support, and frontmatter retry loop.

.workflows/solve-issue.yaml

@@ -20,10 +20,10 @@ 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)."
-    meta:
+    frontmatter:
       type: object
       properties:
         status:
@@ -45,7 +45,7 @@ roles:
       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)."
-    meta:
+    frontmatter:
       type: object
       properties:
         status:
@@ -75,7 +75,7 @@ roles:
       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)."
-    meta:
+    frontmatter:
       type: object
       properties:
         approved:
@@ -95,7 +95,7 @@ roles:
          - 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)."
-    meta:
+    frontmatter:
       type: object
       properties:
         status:
@@ -115,7 +115,7 @@ roles:
       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)."
-    meta:
+    frontmatter:
       type: object
       properties:
         success:
@@ -124,22 +124,22 @@ roles:
 conditions:
   insufficientInfo:
     description: "Planner determined there's not enough info to proceed"
-    expression: "steps[-1].output.status = 'insufficient_info'"
+    expression: "$last('planner').status = 'insufficient_info'"
   devFailed:
     description: "Developer failed to implement"
-    expression: "steps[-1].output.status = 'failed'"
+    expression: "$last('developer').status = 'failed'"
   rejected:
     description: "Reviewer rejected the implementation"
-    expression: "steps[-1].output.approved = false"
+    expression: "$last('reviewer').approved = false"
   fixCode:
     description: "Tester found code issues"
-    expression: "steps[-1].output.status = 'fix_code'"
+    expression: "$last('tester').status = 'fix_code'"
   fixSpec:
     description: "Tester found spec issues"
-    expression: "steps[-1].output.status = 'fix_spec'"
+    expression: "$last('tester').status = 'fix_spec'"
   hookFailed:
     description: "Push hook failed"
-    expression: "steps[-1].output.success = false"
+    expression: "$last('committer').success = false"
 graph:
   $START:
     - role: "planner"

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/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