chore: remove accidental pnpm-lock.yaml

- uwf log list: list log files with sizes
- uwf log show --thread <id>: filter by thread ID
- uwf log show --process <pid>: filter by process ID
- uwf log clean --before <date>: delete old log files
- Tests: 12 new tests covering all subcommands

Implemented by solve-issue workflow, biome fixes applied manually.

Closes #413
Refs #411, #410

packages/cli-workflow/src/__tests__/log.test.ts

@@ -0,0 +1,181 @@
+import { mkdir, readdir, rm, writeFile } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { afterEach, beforeEach, describe, expect, test } from "vitest";
+import { cmdLogClean, cmdLogList, cmdLogShow } from "../commands/log.js";
+
+let storageRoot: string;
+
+beforeEach(async () => {
+  storageRoot = join(tmpdir(), `uwf-log-test-${Date.now()}-${Math.random().toString(36).slice(2)}`);
+  await mkdir(join(storageRoot, "logs"), { recursive: true });
+});
+
+afterEach(async () => {
+  await rm(storageRoot, { recursive: true, force: true });
+});
+
+const entry1 = JSON.stringify({
+  ts: "2026-05-20T10:00:00.000Z",
+  pid: "1716200000000-1234",
+  tag: "W9F3RK2M",
+  msg: "process start",
+  thread: "01J1234ABCDEF",
+  workflow: "solve-issue",
+});
+
+const entry2 = JSON.stringify({
+  ts: "2026-05-20T10:00:01.000Z",
+  pid: "1716200000000-1234",
+  tag: "ABC12345",
+  msg: "step executed",
+  thread: "01J1234ABCDEF",
+  workflow: "solve-issue",
+});
+
+const entry3 = JSON.stringify({
+  ts: "2026-05-20T10:00:02.000Z",
+  pid: "1716200000000-5678",
+  tag: "XYZ98765",
+  msg: "different process",
+  thread: "01JOTHER000000",
+  workflow: "review-code",
+});
+
+const oldEntry = JSON.stringify({
+  ts: "2026-05-19T08:00:00.000Z",
+  pid: "1716200000000-9999",
+  tag: "OLD1TAG1",
+  msg: "old entry",
+  thread: "01JOLD0000000",
+  workflow: "solve-issue",
+});
+
+const olderEntry = JSON.stringify({
+  ts: "2026-05-18T08:00:00.000Z",
+  pid: "1716200000000-0001",
+  tag: "OLD2TAG2",
+  msg: "older entry",
+  thread: "01JOLDER00000",
+  workflow: "review-code",
+});
+
+async function writeLogFiles(): Promise<void> {
+  const logsDir = join(storageRoot, "logs");
+  await writeFile(join(logsDir, "2026-05-20.jsonl"), [entry1, entry2, entry3].join("\n") + "\n");
+  await writeFile(join(logsDir, "2026-05-19.jsonl"), oldEntry + "\n");
+  await writeFile(join(logsDir, "2026-05-18.jsonl"), olderEntry + "\n");
+}
+
+describe("cmdLogList", () => {
+  test("lists log files with sizes sorted by date descending", async () => {
+    await writeLogFiles();
+    const result = await cmdLogList(storageRoot);
+    expect(result).toHaveLength(3);
+    expect(result[0].name).toBe("2026-05-20.jsonl");
+    expect(result[0].date).toBe("2026-05-20");
+    expect(result[0].size).toBeGreaterThan(0);
+    expect(result[1].name).toBe("2026-05-19.jsonl");
+    expect(result[2].name).toBe("2026-05-18.jsonl");
+  });
+
+  test("returns empty array when no log files exist", async () => {
+    const result = await cmdLogList(storageRoot);
+    expect(result).toEqual([]);
+  });
+
+  test("returns empty array when logs directory does not exist", async () => {
+    const noLogsRoot = join(storageRoot, "nonexistent");
+    await mkdir(noLogsRoot, { recursive: true });
+    const result = await cmdLogList(noLogsRoot);
+    expect(result).toEqual([]);
+  });
+});
+
+describe("cmdLogShow", () => {
+  test("filters by thread ID", async () => {
+    await writeLogFiles();
+    const result = await cmdLogShow(storageRoot, {
+      thread: "01J1234ABCDEF",
+      process: null,
+      date: null,
+    });
+    expect(result).toHaveLength(2);
+    expect(result.every((e) => e.thread === "01J1234ABCDEF")).toBe(true);
+  });
+
+  test("filters by process ID", async () => {
+    await writeLogFiles();
+    const result = await cmdLogShow(storageRoot, {
+      thread: null,
+      process: "1716200000000-1234",
+      date: null,
+    });
+    expect(result).toHaveLength(2);
+    expect(result.every((e) => e.pid === "1716200000000-1234")).toBe(true);
+  });
+
+  test("filters by date", async () => {
+    await writeLogFiles();
+    const result = await cmdLogShow(storageRoot, {
+      thread: null,
+      process: null,
+      date: "2026-05-19",
+    });
+    expect(result).toHaveLength(1);
+    expect(result[0].msg).toBe("old entry");
+  });
+
+  test("reads all files when no date filter", async () => {
+    await writeLogFiles();
+    const result = await cmdLogShow(storageRoot, { thread: null, process: null, date: null });
+    expect(result).toHaveLength(5);
+    // sorted by ts ascending
+    expect(result[0].ts).toBe("2026-05-18T08:00:00.000Z");
+    expect(result[4].ts).toBe("2026-05-20T10:00:02.000Z");
+  });
+
+  test("returns empty when no matches", async () => {
+    await writeLogFiles();
+    const result = await cmdLogShow(storageRoot, {
+      thread: "NONEXISTENT",
+      process: null,
+      date: null,
+    });
+    expect(result).toEqual([]);
+  });
+
+  test("combined thread + date filter", async () => {
+    await writeLogFiles();
+    const result = await cmdLogShow(storageRoot, {
+      thread: "01J1234ABCDEF",
+      process: null,
+      date: "2026-05-20",
+    });
+    expect(result).toHaveLength(2);
+    expect(result.every((e) => e.thread === "01J1234ABCDEF")).toBe(true);
+  });
+});
+
+describe("cmdLogClean", () => {
+  test("deletes files before given date", async () => {
+    await writeLogFiles();
+    const result = await cmdLogClean(storageRoot, "2026-05-20");
+    expect(result.deleted).toBe(2);
+    const remaining = await readdir(join(storageRoot, "logs"));
+    expect(remaining).toEqual(["2026-05-20.jsonl"]);
+  });
+
+  test("deletes nothing when all files are newer", async () => {
+    await writeLogFiles();
+    const result = await cmdLogClean(storageRoot, "2026-05-18");
+    expect(result.deleted).toBe(0);
+  });
+
+  test("handles missing logs directory gracefully", async () => {
+    const noLogsRoot = join(storageRoot, "nonexistent");
+    await mkdir(noLogsRoot, { recursive: true });
+    const result = await cmdLogClean(noLogsRoot, "2026-05-20");
+    expect(result).toEqual({ deleted: 0 });
+  });
+});

packages/cli-workflow/src/cli.ts

@@ -14,6 +14,7 @@ import {
   cmdCasSchemaList,
   cmdCasWalk,
 } from "./commands/cas.js";
+import { cmdLogClean, cmdLogList, cmdLogShow } from "./commands/log.js";
 import { cmdSetup, cmdSetupInteractive } from "./commands/setup.js";
 import { cmdSkillCli } from "./commands/skill.js";
 import {
@@ -379,6 +380,55 @@ casSchema
     });
   });
 
+const log = program.command("log").description("Process-level debug logs");
+
+log
+  .command("list")
+  .description("List log files with sizes")
+  .action(() => {
+    const storageRoot = resolveStorageRoot();
+    runAction(async () => {
+      const result = await cmdLogList(storageRoot);
+      writeOutput(result);
+    });
+  });
+
+log
+  .command("show")
+  .description("Show and filter log entries")
+  .option("--thread <thread-id>", "Filter by thread ID")
+  .option("--process <pid>", "Filter by process ID")
+  .option("--date <date>", "Filter by date (YYYY-MM-DD)")
+  .action(
+    (opts: {
+      thread: string | undefined;
+      process: string | undefined;
+      date: string | undefined;
+    }) => {
+      const storageRoot = resolveStorageRoot();
+      runAction(async () => {
+        const result = await cmdLogShow(storageRoot, {
+          thread: opts.thread ?? null,
+          process: opts.process ?? null,
+          date: opts.date ?? null,
+        });
+        writeOutput(result);
+      });
+    },
+  );
+
+log
+  .command("clean")
+  .description("Delete log files older than given date")
+  .requiredOption("--before <date>", "Delete files before this date (YYYY-MM-DD)")
+  .action((opts: { before: string }) => {
+    const storageRoot = resolveStorageRoot();
+    runAction(async () => {
+      const result = await cmdLogClean(storageRoot, opts.before);
+      writeOutput(result);
+    });
+  });
+
 program.parseAsync(process.argv).catch((e: unknown) => {
   const message = e instanceof Error ? e.message : String(e);
   process.stderr.write(`${message}\n`);

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

@@ -0,0 +1,116 @@
+import { readdir, readFile, stat, unlink } from "node:fs/promises";
+import { join } from "node:path";
+
+type LogListItem = {
+  name: string;
+  size: number;
+  date: string;
+};
+
+type LogShowFilter = {
+  thread: string | null;
+  process: string | null;
+  date: string | null;
+};
+
+type LogEntry = {
+  ts: string;
+  pid: string;
+  tag: string;
+  msg: string;
+  thread: string | null;
+  workflow: string | null;
+};
+
+type LogCleanResult = {
+  deleted: number;
+};
+
+function logsDir(storageRoot: string): string {
+  return join(storageRoot, "logs");
+}
+
+async function listLogFiles(dir: string): Promise<Array<string>> {
+  try {
+    const files = await readdir(dir);
+    return files.filter((f) => f.endsWith(".jsonl")).sort();
+  } catch {
+    return [];
+  }
+}
+
+function dateFromFilename(name: string): string {
+  return name.replace(".jsonl", "");
+}
+
+async function parseJsonlFile(path: string): Promise<Array<LogEntry>> {
+  const content = await readFile(path, "utf-8");
+  const lines = content
+    .trim()
+    .split("\n")
+    .filter((l) => l.length > 0);
+  return lines.map((line) => JSON.parse(line) as LogEntry);
+}
+
+export async function cmdLogList(storageRoot: string): Promise<Array<LogListItem>> {
+  const dir = logsDir(storageRoot);
+  const files = await listLogFiles(dir);
+  const items: Array<LogListItem> = [];
+  for (const name of files) {
+    const s = await stat(join(dir, name));
+    items.push({ name, size: s.size, date: dateFromFilename(name) });
+  }
+  // sort by date descending
+  items.sort((a, b) => (a.date > b.date ? -1 : a.date < b.date ? 1 : 0));
+  return items;
+}
+
+export async function cmdLogShow(
+  storageRoot: string,
+  filter: LogShowFilter,
+): Promise<Array<LogEntry>> {
+  const dir = logsDir(storageRoot);
+  let files: Array<string>;
+
+  if (filter.date !== null) {
+    files = [`${filter.date}.jsonl`];
+  } else {
+    files = await listLogFiles(dir);
+  }
+
+  let entries: Array<LogEntry> = [];
+  for (const file of files) {
+    try {
+      const parsed = await parseJsonlFile(join(dir, file));
+      entries = entries.concat(parsed);
+    } catch {
+      // file doesn't exist or is unreadable, skip
+    }
+  }
+
+  if (filter.thread !== null) {
+    entries = entries.filter((e) => e.thread === filter.thread);
+  }
+  if (filter.process !== null) {
+    entries = entries.filter((e) => e.pid === filter.process);
+  }
+
+  entries.sort((a, b) => (a.ts < b.ts ? -1 : a.ts > b.ts ? 1 : 0));
+  return entries;
+}
+
+export async function cmdLogClean(storageRoot: string, before: string): Promise<LogCleanResult> {
+  const dir = logsDir(storageRoot);
+  const files = await listLogFiles(dir);
+  let deleted = 0;
+
+  for (const name of files) {
+    const date = dateFromFilename(name);
+    if (date < before) {
+      await unlink(join(dir, name));
+      deleted++;
+    }
+  }
+
+  return { deleted };
+}

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

@@ -23,7 +23,7 @@ import type {
   WorkflowConfig,
   WorkflowPayload,
 } from "@uncaged/workflow-protocol";
-import { generateUlid } from "@uncaged/workflow-util";
+import { createProcessLogger, generateUlid, type ProcessLogger } from "@uncaged/workflow-util";
 import { config as loadDotenv } from "dotenv";
 import { parse, stringify } from "yaml";
 
@@ -47,6 +47,18 @@ import { materializeWorkflowPayload } from "./workflow.js";
 const END_ROLE = "$END";
 export const THREAD_READ_DEFAULT_QUOTA = 4000;
 
+const PL_THREAD_START = "7HNQ4B2X";
+const PL_MODERATOR = "M3K8V9T1";
+const PL_AGENT_SPAWN = "R5J2W8N4";
+const PL_AGENT_DONE = "C6P9E3H7";
+const PL_THREAD_ARCHIVED = "F4D8Q2K5";
+const PL_STEP_ERROR = "B8T5N1V6";
+
+function failStep(plog: ProcessLogger, message: string): never {
+  plog.log(PL_STEP_ERROR, message, null);
+  fail(message);
+}
+
 type ChainState = {
   startHash: CasRef;
   start: StartNodePayload;
@@ -168,6 +180,10 @@ export async function cmdThreadStart(
   const workflowHash = await resolveWorkflowCasRef(uwf, storageRoot, workflowId, projectRoot);
 
   const threadId = generateUlid(Date.now()) as ThreadId;
+  const plog = createProcessLogger({
+    storageRoot,
+    context: { thread: threadId, workflow: workflowHash },
+  });
   const startPayload: StartNodePayload = {
     workflow: workflowHash,
     prompt,
@@ -183,6 +199,12 @@ export async function cmdThreadStart(
   index[threadId] = headHash;
   await saveThreadsIndex(storageRoot, index);
 
+  plog.log(
+    PL_THREAD_START,
+    `thread created workflow=${workflowHash} thread=${threadId} head=${headHash}`,
+    null,
+  );
+
   return { workflow: workflowHash, thread: threadId };
 }
 
@@ -625,6 +647,7 @@ function resolveAgentConfig(
 }
 
 function spawnAgent(
+  plog: ProcessLogger,
   agent: AgentConfig,
   threadId: ThreadId,
   role: string,
@@ -648,12 +671,12 @@ function spawnAgent(
           ? err.stderr
           : err.stderr.toString("utf8");
     const detail = stderr.trim() !== "" ? `: ${stderr.trim()}` : "";
-    fail(`agent command failed (${agent.command})${detail}`);
+    failStep(plog, `agent command failed (${agent.command})${detail}`);
   }
 
   const line = stdout.trim().split("\n").pop()?.trim() ?? "";
   if (!isCasRef(line)) {
-    fail(`agent stdout is not a valid CAS hash: ${line || "(empty)"}`);
+    failStep(plog, `agent stdout is not a valid CAS hash: ${line || "(empty)"}`);
   }
   return line;
 }
@@ -685,9 +708,15 @@ export async function cmdThreadStep(
     fail(`--count must be a positive integer, got: ${count}`);
   }
 
+  const workflowHash = await resolveActiveThreadWorkflowHash(storageRoot, threadId);
+  const plog = createProcessLogger({
+    storageRoot,
+    context: { thread: threadId, workflow: workflowHash },
+  });
+
   const results: StepOutput[] = [];
   for (let i = 0; i < count; i++) {
-    const result = await cmdThreadStepOnce(storageRoot, threadId, agentOverride);
+    const result = await cmdThreadStepOnce(storageRoot, threadId, agentOverride, plog);
     results.push(result);
     if (result.done) {
       break;
@@ -696,16 +725,31 @@ export async function cmdThreadStep(
   return results;
 }
 
-async function cmdThreadStepOnce(
+async function resolveActiveThreadWorkflowHash(
   storageRoot: string,
   threadId: ThreadId,
-  agentOverride: string | null,
-): Promise<StepOutput> {
+): Promise<CasRef> {
   const index = await loadThreadsIndex(storageRoot);
   const headHash = index[threadId];
   if (headHash === undefined) {
     fail(`thread not active: ${threadId}`);
   }
+  const uwf = await createUwfStore(storageRoot);
+  const chain = walkChain(uwf, headHash);
+  return chain.start.workflow;
+}
+
+async function cmdThreadStepOnce(
+  storageRoot: string,
+  threadId: ThreadId,
+  agentOverride: string | null,
+  plog: ProcessLogger,
+): Promise<StepOutput> {
+  const index = await loadThreadsIndex(storageRoot);
+  const headHash = index[threadId];
+  if (headHash === undefined) {
+    failStep(plog, `thread not active: ${threadId}`);
+  }
 
   const uwf = await createUwfStore(storageRoot);
   const chain = walkChain(uwf, headHash);
@@ -715,10 +759,17 @@ async function cmdThreadStepOnce(
 
   const nextResult = await evaluate(workflow, context);
   if (!nextResult.ok) {
-    fail(nextResult.error.message);
+    failStep(plog, `moderator evaluate failed: ${nextResult.error.message}`);
   }
 
+  plog.log(
+    PL_MODERATOR,
+    `moderator role=${nextResult.value.role} prompt=${nextResult.value.prompt}`,
+    null,
+  );
+
   if (nextResult.value.role === END_ROLE) {
+    plog.log(PL_THREAD_ARCHIVED, `thread archived head=${headHash}`, null);
     await archiveThread(storageRoot, threadId, workflowHash, headHash);
     return {
       workflow: workflowHash,
@@ -733,14 +784,20 @@ async function cmdThreadStepOnce(
   const config = await loadWorkflowConfig(storageRoot);
   const agent = resolveAgentConfig(config, workflow, role, agentOverride);
 
+  plog.log(PL_AGENT_SPAWN, `spawning agent command=${agent.command}`, {
+    args: [...agent.args, threadId, role].join(" "),
+  });
+
   loadDotenv({ path: getEnvPath(storageRoot) });
-  const newHead = spawnAgent(agent, threadId, role, edgePrompt);
+  const newHead = spawnAgent(plog, agent, threadId, role, edgePrompt);
+
+  plog.log(PL_AGENT_DONE, `agent returned head=${newHead}`, null);
 
   // Re-create store to pick up nodes written by the agent subprocess
   const uwfAfter = await createUwfStore(storageRoot);
   const newNode = uwfAfter.store.get(newHead);
   if (newNode === null || newNode.type !== uwfAfter.schemas.stepNode) {
-    fail(`agent returned hash that is not a StepNode: ${newHead}`);
+    failStep(plog, `agent returned hash that is not a StepNode: ${newHead}`);
   }
 
   // Reload threads index to avoid overwriting changes made by the agent subprocess
@@ -752,11 +809,12 @@ async function cmdThreadStepOnce(
   const contextAfter = buildModeratorContext(uwfAfter, chainAfter);
   const afterResult = await evaluate(workflow, contextAfter);
   if (!afterResult.ok) {
-    fail(afterResult.error.message);
+    failStep(plog, `post-step moderator evaluate failed: ${afterResult.error.message}`);
   }
 
   const done = afterResult.value.role === END_ROLE;
   if (done) {
+    plog.log(PL_THREAD_ARCHIVED, `thread archived head=${newHead}`, null);
     await archiveThread(storageRoot, threadId, workflowHash, newHead);
   }
 

packages/workflow-util/__tests__/process-logger.test.ts

@@ -0,0 +1,81 @@
+import { mkdirSync, mkdtempSync, readFileSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { afterEach, describe, expect, test } from "bun:test";
+
+import { createProcessLogger } from "../src/process-logger/index.js";
+
+function logDateKey(date: Date): string {
+  return date.toISOString().slice(0, 10);
+}
+
+describe("createProcessLogger", () => {
+  let tmpDir: string;
+
+  afterEach(() => {
+    if (tmpDir !== undefined) {
+      rmSync(tmpDir, { recursive: true, force: true });
+    }
+  });
+
+  test("writes init and log lines to dated JSONL under storage root", () => {
+    tmpDir = mkdtempSync(join(tmpdir(), "uwf-process-log-"));
+    const plog = createProcessLogger({
+      storageRoot: tmpDir,
+      context: { thread: "THREAD01", workflow: "WORKFLOW01" },
+    });
+
+    expect(plog.pid).toMatch(/^\d+-\d+$/);
+
+    plog.log("7NQW4HBT", "moderator selected role=planner", null);
+
+    const logPath = join(tmpDir, "logs", `${logDateKey(new Date())}.jsonl`);
+    const lines = readFileSync(logPath, "utf8")
+      .trim()
+      .split("\n")
+      .map((line) => JSON.parse(line) as Record<string, string>);
+
+    expect(lines).toHaveLength(2);
+    expect(lines[0]?.tag).toBe("W9F3RK2M");
+    expect(lines[0]?.pid).toBe(plog.pid);
+    expect(lines[0]?.thread).toBe("THREAD01");
+    expect(lines[0]?.workflow).toBe("WORKFLOW01");
+    expect(lines[0]?.msg).toContain("process start");
+    expect(lines[0]?.msg).toContain("node=");
+
+    expect(lines[1]?.tag).toBe("7NQW4HBT");
+    expect(lines[1]?.msg).toBe("moderator selected role=planner");
+    expect(lines[1]?.thread).toBe("THREAD01");
+    expect(lines[1]?.workflow).toBe("WORKFLOW01");
+  });
+
+  test("creates logs directory when missing", () => {
+    tmpDir = mkdtempSync(join(tmpdir(), "uwf-process-log-"));
+    createProcessLogger({
+      storageRoot: tmpDir,
+      context: { thread: null, workflow: null },
+    });
+    mkdirSync(join(tmpDir, "logs"), { recursive: true });
+    expect(() =>
+      readFileSync(join(tmpDir, "logs", `${logDateKey(new Date())}.jsonl`), "utf8"),
+    ).not.toThrow();
+  });
+
+  test("merges per-call context into the JSONL entry", () => {
+    tmpDir = mkdtempSync(join(tmpdir(), "uwf-process-log-"));
+    const plog = createProcessLogger({
+      storageRoot: tmpDir,
+      context: { thread: "T1", workflow: null },
+    });
+    plog.log("M3K8V9T1", "spawn agent", { command: "uwf-hermes", args: "tid role" });
+
+    const logPath = join(tmpDir, "logs", `${logDateKey(new Date())}.jsonl`);
+    const lines = readFileSync(logPath, "utf8")
+      .trim()
+      .split("\n")
+      .map((line) => JSON.parse(line) as Record<string, string>);
+    const last = lines[lines.length - 1];
+    expect(last?.command).toBe("uwf-hermes");
+    expect(last?.args).toBe("tid role");
+  });
+});

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

@@ -26,6 +26,7 @@ uwf workflow list                 # list all registered workflows
 uwf thread start <workflow> -p <prompt>           # create a thread (no execution)
 uwf thread step <thread-id>                       # execute one moderator→agent→extract cycle
                [--agent <cmd>]                    # override agent command
+               [-c, --count <number>]             # run multiple steps (default: 1)
 uwf thread show <thread-id>                       # show thread head pointer
 uwf thread list                                   # list active threads
                [--all]                            # include archived threads
@@ -56,6 +57,17 @@ uwf cas schema list               # list all registered schemas
 uwf cas schema get <hash>         # show a schema by its type hash
 \`\`\`
 
+## Log Commands
+
+\`\`\`
+uwf log list                      # list log files with sizes
+uwf log show                      # show all log entries
+           [--thread <thread-id>] # filter by thread ID
+           [--process <pid>]      # filter by process ID
+           [--date <YYYY-MM-DD>]  # filter by date
+uwf log clean --before <date>     # delete log files before given date
+\`\`\`
+
 ## Global Options
 
 \`\`\`
@@ -69,6 +81,7 @@ uwf -V, --version                 # print version
 - **Thread**: A single workflow execution (ULID). State is an immutable CAS chain; active threads are indexed in \`threads.yaml\`.
 - **Step**: One moderator→agent→extract cycle. Run \`uwf thread step\` repeatedly until \`$END\`.
 - **CAS**: Content-Addressed Storage — all nodes are immutable and identified by hash.
-- **Role**: Named actor with goal, capabilities, procedure, output, and meta; the moderator routes between roles.
+- **Role**: Named actor with goal, capabilities, procedure, output, and frontmatter schema; the moderator routes between roles.
+- **Edge Prompt**: Required instruction on each graph edge — the moderator's dispatch message to the agent.
 `;
 }

packages/workflow-util/src/index.ts

@@ -13,6 +13,13 @@ export {
   validateFrontmatter,
 } from "./frontmatter-markdown/index.js";
 export { createLogger } from "./logger.js";
+export { createProcessLogger } from "./process-logger/index.js";
+export type {
+  CreateProcessLoggerOptions,
+  ProcessLogFn,
+  ProcessLogger,
+  ProcessLoggerContext,
+} from "./process-logger/index.js";
 export { normalizeRefsField } from "./refs-field.js";
 export { err, ok } from "./result.js";
 export { getDefaultWorkflowStorageRoot, getGlobalCasDir } from "./storage-root.js";

packages/workflow-util/src/logger.ts

@@ -1,28 +1,8 @@
 import { appendFileSync } from "node:fs";
 
-import { CROCKFORD_BASE32_ALPHABET } from "./base32.js";
+import { assertValidLogTag } from "./process-logger/log-tag.js";
 import type { CreateLoggerOptions, LogFn } from "./types.js";
 
-const TAG_LENGTH = 8;
-
-const TAG_CHAR_SET: ReadonlySet<string> = new Set(CROCKFORD_BASE32_ALPHABET.split(""));
-
-function assertValidLogTag(tag: string): void {
-  if (tag.length !== TAG_LENGTH) {
-    throw new Error(`log tag must be exactly ${TAG_LENGTH} characters`);
-  }
-  for (let i = 0; i < tag.length; i++) {
-    const ch = tag[i];
-    if (ch === undefined) {
-      throw new Error("log tag validation failed");
-    }
-    const upper = ch.toUpperCase();
-    if (!TAG_CHAR_SET.has(upper)) {
-      throw new Error(`invalid Crockford Base32 character in log tag: ${ch}`);
-    }
-  }
-}
-
 /** Append one JSONL log record: `{ tag, content, timestamp }` per RFC-001. */
 export function createLogger(options: CreateLoggerOptions): LogFn {
   if (options.sink.kind === "stderr") {

packages/workflow-util/src/process-logger/index.ts

@@ -0,0 +1,7 @@
+export { createProcessLogger } from "./process-logger.js";
+export type {
+  CreateProcessLoggerOptions,
+  ProcessLogFn,
+  ProcessLogger,
+  ProcessLoggerContext,
+} from "./types.js";

packages/workflow-util/src/process-logger/log-tag.ts

@@ -0,0 +1,21 @@
+import { CROCKFORD_BASE32_ALPHABET } from "../base32.js";
+
+const TAG_LENGTH = 8;
+
+const TAG_CHAR_SET: ReadonlySet<string> = new Set(CROCKFORD_BASE32_ALPHABET.split(""));
+
+export function assertValidLogTag(tag: string): void {
+  if (tag.length !== TAG_LENGTH) {
+    throw new Error(`log tag must be exactly ${TAG_LENGTH} characters`);
+  }
+  for (let i = 0; i < tag.length; i++) {
+    const ch = tag[i];
+    if (ch === undefined) {
+      throw new Error("log tag validation failed");
+    }
+    const upper = ch.toUpperCase();
+    if (!TAG_CHAR_SET.has(upper)) {
+      throw new Error(`invalid Crockford Base32 character in log tag: ${ch}`);
+    }
+  }
+}

packages/workflow-util/src/process-logger/process-logger.ts

@@ -0,0 +1,78 @@
+import { appendFileSync, mkdirSync } from "node:fs";
+import { join } from "node:path";
+
+import { getDefaultWorkflowStorageRoot } from "../storage-root.js";
+import { assertValidLogTag } from "./log-tag.js";
+import type { CreateProcessLoggerOptions, ProcessLogger, ProcessLoggerContext } from "./types.js";
+
+const INIT_TAG = "W9F3RK2M";
+
+function logDateKey(date: Date): string {
+  return date.toISOString().slice(0, 10);
+}
+
+function getProcessLogsDir(storageRoot: string): string {
+  return join(storageRoot, "logs");
+}
+
+function getProcessLogFilePath(storageRoot: string, date: Date): string {
+  return join(getProcessLogsDir(storageRoot), `${logDateKey(date)}.jsonl`);
+}
+
+function buildEntry(
+  processId: string,
+  tag: string,
+  msg: string,
+  baseContext: ProcessLoggerContext,
+  extra: Record<string, string> | null,
+): Record<string, string> {
+  const entry: Record<string, string> = {
+    ts: new Date().toISOString(),
+    pid: processId,
+    tag: tag.toUpperCase(),
+    msg,
+  };
+  if (baseContext.thread !== null) {
+    entry.thread = baseContext.thread;
+  }
+  if (baseContext.workflow !== null) {
+    entry.workflow = baseContext.workflow;
+  }
+  if (extra !== null) {
+    for (const [key, value] of Object.entries(extra)) {
+      entry[key] = value;
+    }
+  }
+  return entry;
+}
+
+function appendEntry(filePath: string, entry: Record<string, string>): void {
+  appendFileSync(filePath, `${JSON.stringify(entry)}\n`, "utf8");
+}
+
+/** Process-scoped debug logger — append-only JSONL under `<storageRoot>/logs/YYYY-MM-DD.jsonl`. */
+export function createProcessLogger(options: CreateProcessLoggerOptions): ProcessLogger {
+  const storageRoot = options.storageRoot ?? getDefaultWorkflowStorageRoot();
+  const processId = `${Date.now()}-${process.pid}`;
+  const baseContext = options.context;
+  const logFilePath = getProcessLogFilePath(storageRoot, new Date());
+
+  mkdirSync(getProcessLogsDir(storageRoot), { recursive: true });
+
+  const log: ProcessLogger["log"] = (tag, msg, context = null) => {
+    assertValidLogTag(tag);
+    appendEntry(logFilePath, buildEntry(processId, tag, msg, baseContext, context));
+  };
+
+  const argvSummary = JSON.stringify(process.argv);
+  const initParts = [`argv=${argvSummary}`, `node=${process.version}`];
+  if (baseContext.thread !== null) {
+    initParts.push(`thread=${baseContext.thread}`);
+  }
+  if (baseContext.workflow !== null) {
+    initParts.push(`workflow=${baseContext.workflow}`);
+  }
+  log(INIT_TAG, `process start ${initParts.join(" ")}`, null);
+
+  return { pid: processId, log };
+}

packages/workflow-util/src/process-logger/types.ts

@@ -0,0 +1,20 @@
+export type ProcessLoggerContext = {
+  thread: string | null;
+  workflow: string | null;
+};
+
+export type CreateProcessLoggerOptions = {
+  storageRoot: string | null;
+  context: ProcessLoggerContext;
+};
+
+export type ProcessLogFn = (
+  tag: string,
+  msg: string,
+  context: Record<string, string> | null,
+) => void;
+
+export type ProcessLogger = {
+  pid: string;
+  log: ProcessLogFn;
+};