add magenta log prefixes for delegated subagents (#387)

When delegate() runs multiple subagents in parallel, their logs
interleave without visual distinction. Use AsyncLocalStorage to
automatically prefix every log line inside runSubagent() with the
task label in magenta (e.g. [frontend-review]).

Co-authored-by: Cursor <cursoragent@cursor.com>

entry

@@ -135589,6 +135589,7 @@ var Effort = type.enumerated("mini", "auto", "max");
 // utils/log.ts
 var core = __toESM(require_core(), 1);
 var import_table = __toESM(require_src(), 1);
+import { AsyncLocalStorage } from "node:async_hooks";
 
 // utils/globals.ts
 import { existsSync } from "node:fs";
@@ -135597,6 +135598,23 @@ var isGitHubActions = !!process.env.GITHUB_ACTIONS;
 var isInsideDocker = existsSync("/.dockerenv");
 
 // utils/log.ts
+var logContext = new AsyncLocalStorage();
+var MAGENTA = "\x1B[35m";
+var RESET = "\x1B[0m";
+function withLogPrefix(prefix, fn2) {
+  return logContext.run({ prefix }, fn2);
+}
+function prefixLines(message) {
+  const ctx = logContext.getStore();
+  if (!ctx) return message;
+  const colored = `${MAGENTA}${ctx.prefix}${RESET} `;
+  return message.split("\n").map((line) => `${colored}${line}`).join("\n");
+}
+function prefixPlain(name) {
+  const ctx = logContext.getStore();
+  if (!ctx) return name;
+  return `${ctx.prefix} ${name}`;
+}
 var isRunnerDebugEnabled = () => core.isDebug();
 var isLocalDebugEnabled = () => process.env.LOG_LEVEL === "debug" || process.env.ACTIONS_STEP_DEBUG === "true";
 var isDebugEnabled = () => isLocalDebugEnabled() || isRunnerDebugEnabled();
@@ -135612,10 +135630,11 @@ ${arg.stack}`;
   }).join(" ");
 }
 function startGroup2(name) {
+  const prefixed = prefixPlain(name);
   if (isGitHubActions) {
-    core.startGroup(name);
+    core.startGroup(prefixed);
   } else {
-    console.group(name);
+    console.group(prefixed);
   }
 }
 function endGroup2() {
@@ -135688,7 +135707,7 @@ function boxString(text, options) {
 }
 function box(text, options) {
   const boxContent = boxString(text, options);
-  core.info(boxContent);
+  core.info(prefixLines(boxContent));
 }
 async function writeSummary(text) {
   if (!isGitHubActions) return;
@@ -135708,42 +135727,42 @@ function printTable(rows, options) {
   );
   const formatted = (0, import_table.table)(tableData);
   if (title) {
-    core.info(`
+    core.info(prefixLines(`
-${title}`);
+${title}`));
   }
-  core.info(`
+  core.info(prefixLines(`
 ${formatted}
-`);
+`));
 }
 function separator(length = 50) {
   const separatorText = "\u2500".repeat(length);
-  core.info(separatorText);
+  core.info(prefixLines(separatorText));
 }
 var log = {
   /** Print info message */
   info: (...args2) => {
-    core.info(`${ts()}${formatArgs(args2)}`);
+    core.info(prefixLines(`${ts()}${formatArgs(args2)}`));
   },
   /** Print a warning message. Use only for warnings that should be displayed in the job summary. */
   warning: (...args2) => {
-    core.warning(`${ts()}${formatArgs(args2)}`);
+    core.warning(prefixLines(`${ts()}${formatArgs(args2)}`));
   },
   /** Print an error message. Use only for errors that should be displayed in the job summary. */
   error: (...args2) => {
-    core.error(`${ts()}${formatArgs(args2)}`);
+    core.error(prefixLines(`${ts()}${formatArgs(args2)}`));
   },
   /** Print success message */
   success: (...args2) => {
-    core.info(`${ts()}\xBB ${formatArgs(args2)}`);
+    core.info(prefixLines(`${ts()}\xBB ${formatArgs(args2)}`));
   },
   /** Print debug message (only when debug mode is enabled) */
   debug: (...args2) => {
     if (isRunnerDebugEnabled()) {
-      core.debug(formatArgs(args2));
+      core.debug(prefixLines(formatArgs(args2)));
       return;
     }
     if (isLocalDebugEnabled()) {
-      core.info(`${ts()}[DEBUG] ${formatArgs(args2)}`);
+      core.info(prefixLines(`${ts()}[DEBUG] ${formatArgs(args2)}`));
     }
   },
   /** Print a formatted box with text */
@@ -136443,41 +136462,43 @@ ${params.instructions}`;
   };
 }
 async function runSubagent(params) {
-  params.subagent.keepAliveInterval = setInterval(markActivity, 3e4);
+  return withLogPrefix(`[${params.subagent.label}]`, async () => {
-  const mcpServer = await startSubagentMcpServer({
+    params.subagent.keepAliveInterval = setInterval(markActivity, 3e4);
-    ctx: params.ctx,
+    const mcpServer = await startSubagentMcpServer({
-    subagentId: params.subagent.id
-  });
-  const subagentTmpdir = join(params.ctx.tmpdir, params.subagent.id);
-  mkdirSync(subagentTmpdir, { recursive: true });
-  try {
-    const subagentPayload = { ...params.ctx.payload, effort: params.effort };
-    const subagentInstructions = buildSubagentInstructions({
       ctx: params.ctx,
-      label: params.subagent.label,
+      subagentId: params.subagent.id
-      instructions: params.instructions
     });
-    const result = await params.ctx.agent.run({
+    const subagentTmpdir = join(params.ctx.tmpdir, params.subagent.id);
-      payload: subagentPayload,
+    mkdirSync(subagentTmpdir, { recursive: true });
-      mcpServerUrl: mcpServer.url,
-      tmpdir: subagentTmpdir,
-      instructions: subagentInstructions
-    });
-    params.subagent.usage = result.usage;
-    writeFileSync(params.subagent.stdoutFilePath, result.output ?? "", "utf-8");
-    completeSubagent({ ctx: params.ctx, subagent: params.subagent, success: result.success });
-    return { success: result.success, error: result.error };
-  } catch (err) {
-    const errorMessage = err instanceof Error ? err.message : String(err);
     try {
-      writeFileSync(params.subagent.stdoutFilePath, "", "utf-8");
+      const subagentPayload = { ...params.ctx.payload, effort: params.effort };
-    } catch {
+      const subagentInstructions = buildSubagentInstructions({
+        ctx: params.ctx,
+        label: params.subagent.label,
+        instructions: params.instructions
+      });
+      const result = await params.ctx.agent.run({
+        payload: subagentPayload,
+        mcpServerUrl: mcpServer.url,
+        tmpdir: subagentTmpdir,
+        instructions: subagentInstructions
+      });
+      params.subagent.usage = result.usage;
+      writeFileSync(params.subagent.stdoutFilePath, result.output ?? "", "utf-8");
+      completeSubagent({ ctx: params.ctx, subagent: params.subagent, success: result.success });
+      return { success: result.success, error: result.error };
+    } catch (err) {
+      const errorMessage = err instanceof Error ? err.message : String(err);
+      try {
+        writeFileSync(params.subagent.stdoutFilePath, "", "utf-8");
+      } catch {
+      }
+      completeSubagent({ ctx: params.ctx, subagent: params.subagent, success: false });
+      return { success: false, error: errorMessage };
+    } finally {
+      await mcpServer.stop();
     }
-    completeSubagent({ ctx: params.ctx, subagent: params.subagent, success: false });
+  });
-    return { success: false, error: errorMessage };
-  } finally {
-    await mcpServer.stop();
-  }
 }
 
 // mcp/askQuestion.ts

get-installation-token/entry

@@ -25507,6 +25507,7 @@ var core3 = __toESM(require_core(), 1);
 // utils/log.ts
 var core = __toESM(require_core(), 1);
 var import_table = __toESM(require_src(), 1);
+import { AsyncLocalStorage } from "node:async_hooks";
 
 // utils/globals.ts
 import { existsSync } from "node:fs";
@@ -25515,6 +25516,20 @@ var isGitHubActions = !!process.env.GITHUB_ACTIONS;
 var isInsideDocker = existsSync("/.dockerenv");
 
 // utils/log.ts
+var logContext = new AsyncLocalStorage();
+var MAGENTA = "\x1B[35m";
+var RESET = "\x1B[0m";
+function prefixLines(message) {
+  const ctx = logContext.getStore();
+  if (!ctx) return message;
+  const colored = `${MAGENTA}${ctx.prefix}${RESET} `;
+  return message.split("\n").map((line) => `${colored}${line}`).join("\n");
+}
+function prefixPlain(name) {
+  const ctx = logContext.getStore();
+  if (!ctx) return name;
+  return `${ctx.prefix} ${name}`;
+}
 var isRunnerDebugEnabled = () => core.isDebug();
 var isLocalDebugEnabled = () => process.env.LOG_LEVEL === "debug" || process.env.ACTIONS_STEP_DEBUG === "true";
 var isDebugEnabled = () => isLocalDebugEnabled() || isRunnerDebugEnabled();
@@ -25530,10 +25545,11 @@ ${arg.stack}`;
   }).join(" ");
 }
 function startGroup2(name) {
+  const prefixed = prefixPlain(name);
   if (isGitHubActions) {
-    core.startGroup(name);
+    core.startGroup(prefixed);
   } else {
-    console.group(name);
+    console.group(prefixed);
   }
 }
 function endGroup2() {
@@ -25606,7 +25622,7 @@ function boxString(text, options) {
 }
 function box(text, options) {
   const boxContent = boxString(text, options);
-  core.info(boxContent);
+  core.info(prefixLines(boxContent));
 }
 function printTable(rows, options) {
   const { title } = options || {};
@@ -25620,42 +25636,42 @@ function printTable(rows, options) {
   );
   const formatted = (0, import_table.table)(tableData);
   if (title) {
-    core.info(`
+    core.info(prefixLines(`
-${title}`);
+${title}`));
   }
-  core.info(`
+  core.info(prefixLines(`
 ${formatted}
-`);
+`));
 }
 function separator(length = 50) {
   const separatorText = "\u2500".repeat(length);
-  core.info(separatorText);
+  core.info(prefixLines(separatorText));
 }
 var log = {
   /** Print info message */
   info: (...args) => {
-    core.info(`${ts()}${formatArgs(args)}`);
+    core.info(prefixLines(`${ts()}${formatArgs(args)}`));
   },
   /** Print a warning message. Use only for warnings that should be displayed in the job summary. */
   warning: (...args) => {
-    core.warning(`${ts()}${formatArgs(args)}`);
+    core.warning(prefixLines(`${ts()}${formatArgs(args)}`));
   },
   /** Print an error message. Use only for errors that should be displayed in the job summary. */
   error: (...args) => {
-    core.error(`${ts()}${formatArgs(args)}`);
+    core.error(prefixLines(`${ts()}${formatArgs(args)}`));
   },
   /** Print success message */
   success: (...args) => {
-    core.info(`${ts()}\xBB ${formatArgs(args)}`);
+    core.info(prefixLines(`${ts()}\xBB ${formatArgs(args)}`));
   },
   /** Print debug message (only when debug mode is enabled) */
   debug: (...args) => {
     if (isRunnerDebugEnabled()) {
-      core.debug(formatArgs(args));
+      core.debug(prefixLines(formatArgs(args)));
       return;
     }
     if (isLocalDebugEnabled()) {
-      core.info(`${ts()}[DEBUG] ${formatArgs(args)}`);
+      core.info(prefixLines(`${ts()}[DEBUG] ${formatArgs(args)}`));
     }
   },
   /** Print a formatted box with text */

mcp/subagent.ts

@@ -6,6 +6,7 @@ import type { Effort } from "../external.ts";
 import { ghPullfrogMcpName } from "../external.ts";
 import { markActivity } from "../utils/activity.ts";
 import type { ResolvedInstructions } from "../utils/instructions.ts";
+import { withLogPrefix } from "../utils/log.ts";
 import { type SubagentState, startSubagentMcpServer, type ToolContext } from "./server.ts";
 
 type CreateSubagentParams = {
@@ -132,41 +133,43 @@ type RunSubagentResult = {
 };
 
 export async function runSubagent(params: RunSubagentParams): Promise<RunSubagentResult> {
-  params.subagent.keepAliveInterval = setInterval(markActivity, 30_000);
+  return withLogPrefix(`[${params.subagent.label}]`, async () => {
-  const mcpServer = await startSubagentMcpServer({
+    params.subagent.keepAliveInterval = setInterval(markActivity, 30_000);
-    ctx: params.ctx,
+    const mcpServer = await startSubagentMcpServer({
-    subagentId: params.subagent.id,
-  });
-  // each subagent gets its own tmpdir so parallel agents don't clobber config files
-  const subagentTmpdir = join(params.ctx.tmpdir, params.subagent.id);
-  mkdirSync(subagentTmpdir, { recursive: true });
-  try {
-    const subagentPayload = { ...params.ctx.payload, effort: params.effort };
-    const subagentInstructions = buildSubagentInstructions({
       ctx: params.ctx,
-      label: params.subagent.label,
+      subagentId: params.subagent.id,
-      instructions: params.instructions,
     });
-    const result = await params.ctx.agent.run({
+    // each subagent gets its own tmpdir so parallel agents don't clobber config files
-      payload: subagentPayload,
+    const subagentTmpdir = join(params.ctx.tmpdir, params.subagent.id);
-      mcpServerUrl: mcpServer.url,
+    mkdirSync(subagentTmpdir, { recursive: true });
-      tmpdir: subagentTmpdir,
-      instructions: subagentInstructions,
-    });
-    params.subagent.usage = result.usage;
-    writeFileSync(params.subagent.stdoutFilePath, result.output ?? "", "utf-8");
-    completeSubagent({ ctx: params.ctx, subagent: params.subagent, success: result.success });
-    return { success: result.success, error: result.error };
-  } catch (err) {
-    const errorMessage = err instanceof Error ? err.message : String(err);
     try {
-      writeFileSync(params.subagent.stdoutFilePath, "", "utf-8");
+      const subagentPayload = { ...params.ctx.payload, effort: params.effort };
-    } catch {
+      const subagentInstructions = buildSubagentInstructions({
-      // best-effort
+        ctx: params.ctx,
+        label: params.subagent.label,
+        instructions: params.instructions,
+      });
+      const result = await params.ctx.agent.run({
+        payload: subagentPayload,
+        mcpServerUrl: mcpServer.url,
+        tmpdir: subagentTmpdir,
+        instructions: subagentInstructions,
+      });
+      params.subagent.usage = result.usage;
+      writeFileSync(params.subagent.stdoutFilePath, result.output ?? "", "utf-8");
+      completeSubagent({ ctx: params.ctx, subagent: params.subagent, success: result.success });
+      return { success: result.success, error: result.error };
+    } catch (err) {
+      const errorMessage = err instanceof Error ? err.message : String(err);
+      try {
+        writeFileSync(params.subagent.stdoutFilePath, "", "utf-8");
+      } catch {
+        // best-effort
+      }
+      completeSubagent({ ctx: params.ctx, subagent: params.subagent, success: false });
+      return { success: false, error: errorMessage };
+    } finally {
+      await mcpServer.stop();
     }
-    completeSubagent({ ctx: params.ctx, subagent: params.subagent, success: false });
+  });
-    return { success: false, error: errorMessage };
-  } finally {
-    await mcpServer.stop();
-  }
 }

post

@@ -28846,6 +28846,7 @@ var require_semver2 = __commonJS({
 // utils/log.ts
 var core = __toESM(require_core(), 1);
 var import_table = __toESM(require_src(), 1);
+import { AsyncLocalStorage } from "node:async_hooks";
 
 // utils/globals.ts
 import { existsSync } from "node:fs";
@@ -28854,6 +28855,20 @@ var isGitHubActions = !!process.env.GITHUB_ACTIONS;
 var isInsideDocker = existsSync("/.dockerenv");
 
 // utils/log.ts
+var logContext = new AsyncLocalStorage();
+var MAGENTA = "\x1B[35m";
+var RESET = "\x1B[0m";
+function prefixLines(message) {
+  const ctx = logContext.getStore();
+  if (!ctx) return message;
+  const colored = `${MAGENTA}${ctx.prefix}${RESET} `;
+  return message.split("\n").map((line) => `${colored}${line}`).join("\n");
+}
+function prefixPlain(name) {
+  const ctx = logContext.getStore();
+  if (!ctx) return name;
+  return `${ctx.prefix} ${name}`;
+}
 var isRunnerDebugEnabled = () => core.isDebug();
 var isLocalDebugEnabled = () => process.env.LOG_LEVEL === "debug" || process.env.ACTIONS_STEP_DEBUG === "true";
 var isDebugEnabled = () => isLocalDebugEnabled() || isRunnerDebugEnabled();
@@ -28869,10 +28884,11 @@ ${arg.stack}`;
   }).join(" ");
 }
 function startGroup2(name) {
+  const prefixed = prefixPlain(name);
   if (isGitHubActions) {
-    core.startGroup(name);
+    core.startGroup(prefixed);
   } else {
-    console.group(name);
+    console.group(prefixed);
   }
 }
 function endGroup2() {
@@ -28945,7 +28961,7 @@ function boxString(text, options) {
 }
 function box(text, options) {
   const boxContent = boxString(text, options);
-  core.info(boxContent);
+  core.info(prefixLines(boxContent));
 }
 function printTable(rows, options) {
   const { title } = options || {};
@@ -28959,42 +28975,42 @@ function printTable(rows, options) {
   );
   const formatted = (0, import_table.table)(tableData);
   if (title) {
-    core.info(`
+    core.info(prefixLines(`
-${title}`);
+${title}`));
   }
-  core.info(`
+  core.info(prefixLines(`
 ${formatted}
-`);
+`));
 }
 function separator(length = 50) {
   const separatorText = "\u2500".repeat(length);
-  core.info(separatorText);
+  core.info(prefixLines(separatorText));
 }
 var log = {
   /** Print info message */
   info: (...args2) => {
-    core.info(`${ts()}${formatArgs(args2)}`);
+    core.info(prefixLines(`${ts()}${formatArgs(args2)}`));
   },
   /** Print a warning message. Use only for warnings that should be displayed in the job summary. */
   warning: (...args2) => {
-    core.warning(`${ts()}${formatArgs(args2)}`);
+    core.warning(prefixLines(`${ts()}${formatArgs(args2)}`));
   },
   /** Print an error message. Use only for errors that should be displayed in the job summary. */
   error: (...args2) => {
-    core.error(`${ts()}${formatArgs(args2)}`);
+    core.error(prefixLines(`${ts()}${formatArgs(args2)}`));
   },
   /** Print success message */
   success: (...args2) => {
-    core.info(`${ts()}\xBB ${formatArgs(args2)}`);
+    core.info(prefixLines(`${ts()}\xBB ${formatArgs(args2)}`));
   },
   /** Print debug message (only when debug mode is enabled) */
   debug: (...args2) => {
     if (isRunnerDebugEnabled()) {
-      core.debug(formatArgs(args2));
+      core.debug(prefixLines(formatArgs(args2)));
       return;
     }
     if (isLocalDebugEnabled()) {
-      core.info(`${ts()}[DEBUG] ${formatArgs(args2)}`);
+      core.info(prefixLines(`${ts()}[DEBUG] ${formatArgs(args2)}`));
     }
   },
   /** Print a formatted box with text */

utils/log.ts

@@ -2,11 +2,43 @@
  * Logging utilities that work well in both local and GitHub Actions environments
  */
 
+import { AsyncLocalStorage } from "node:async_hooks";
 import * as core from "@actions/core";
 import { table } from "table";
 import type { AgentUsage } from "../agents/shared.ts";
 import { isGitHubActions, isInsideDocker } from "./globals.ts";
 
+// --- subagent log prefix via AsyncLocalStorage ---
+
+type LogContext = { prefix: string };
+
+const logContext = new AsyncLocalStorage<LogContext>();
+
+const MAGENTA = "\x1b[35m";
+const RESET = "\x1b[0m";
+
+/** run `fn` with every log line prefixed by `prefix` (e.g. "[task-label]") in magenta */
+export function withLogPrefix<T>(prefix: string, fn: () => Promise<T>): Promise<T> {
+  return logContext.run({ prefix }, fn);
+}
+
+function prefixLines(message: string): string {
+  const ctx = logContext.getStore();
+  if (!ctx) return message;
+  const colored = `${MAGENTA}${ctx.prefix}${RESET} `;
+  return message
+    .split("\n")
+    .map((line) => `${colored}${line}`)
+    .join("\n");
+}
+
+/** plain-text prefix (no ANSI) for GitHub Actions group names */
+function prefixPlain(name: string): string {
+  const ctx = logContext.getStore();
+  if (!ctx) return name;
+  return `${ctx.prefix} ${name}`;
+}
+
 const isRunnerDebugEnabled = () => core.isDebug();
 
 const isLocalDebugEnabled = () =>
@@ -36,10 +68,11 @@ function formatArgs(args: unknown[]): string {
  * Start a collapsed group (GitHub Actions) or regular group (local)
  */
 function startGroup(name: string): void {
+  const prefixed = prefixPlain(name);
   if (isGitHubActions) {
-    core.startGroup(name);
+    core.startGroup(prefixed);
   } else {
-    console.group(name);
+    console.group(prefixed);
   }
 }
 
@@ -153,7 +186,7 @@ function box(
   }
 ): void {
   const boxContent = boxString(text, options);
-  core.info(boxContent);
+  core.info(prefixLines(boxContent));
 }
 
 /**
@@ -200,9 +233,9 @@ function printTable(
   const formatted = table(tableData);
 
   if (title) {
-    core.info(`\n${title}`);
+    core.info(prefixLines(`\n${title}`));
   }
-  core.info(`\n${formatted}\n`);
+  core.info(prefixLines(`\n${formatted}\n`));
 }
 
 /**
@@ -210,7 +243,7 @@ function printTable(
  */
 function separator(length: number = 50): void {
   const separatorText = "─".repeat(length);
-  core.info(separatorText);
+  core.info(prefixLines(separatorText));
 }
 
 /**
@@ -219,32 +252,32 @@ function separator(length: number = 50): void {
 export const log = {
   /** Print info message */
   info: (...args: unknown[]): void => {
-    core.info(`${ts()}${formatArgs(args)}`);
+    core.info(prefixLines(`${ts()}${formatArgs(args)}`));
   },
 
   /** Print a warning message. Use only for warnings that should be displayed in the job summary. */
   warning: (...args: unknown[]): void => {
-    core.warning(`${ts()}${formatArgs(args)}`);
+    core.warning(prefixLines(`${ts()}${formatArgs(args)}`));
   },
 
   /** Print an error message. Use only for errors that should be displayed in the job summary. */
   error: (...args: unknown[]): void => {
-    core.error(`${ts()}${formatArgs(args)}`);
+    core.error(prefixLines(`${ts()}${formatArgs(args)}`));
   },
 
   /** Print success message */
   success: (...args: unknown[]): void => {
-    core.info(`${ts()}» ${formatArgs(args)}`);
+    core.info(prefixLines(`${ts()}» ${formatArgs(args)}`));
   },
 
   /** Print debug message (only when debug mode is enabled) */
   debug: (...args: unknown[]): void => {
     if (isRunnerDebugEnabled()) {
-      core.debug(formatArgs(args));
+      core.debug(prefixLines(formatArgs(args)));
       return;
     }
     if (isLocalDebugEnabled()) {
-      core.info(`${ts()}[DEBUG] ${formatArgs(args)}`);
+      core.info(prefixLines(`${ts()}[DEBUG] ${formatArgs(args)}`));
     }
   },