diff --git a/packages/cli/src/cli.ts b/packages/cli/src/cli.ts
index 12b662bc..0721dc74 100644
--- a/packages/cli/src/cli.ts
+++ b/packages/cli/src/cli.ts
@@ -80,6 +80,7 @@ import {
   startLaunchMetadataRecording,
   type LaunchMetadataRun
 } from './launch-metadata.js';
+import { createLogger } from './logger.js';
 import {
   buildPersonaSourceDirectories,
   defaultCwdPersonaDir,
@@ -95,6 +96,8 @@ import { runPersonaCompileCommand } from './persona-compile.js';
 import { pickPersona, type PickCandidate, type PickResult } from './persona-picker.js';
 import { recordRecent, loadRecents, runPersonaPickerTui, type TuiCandidate } from './persona-tui.js';
 
+const launchMetadataLog = createLogger('launch-metadata');
+
 const USAGE = `Usage: agentworkforce <command> [args...]
 
 Run with no arguments inside a TTY to open an interactive persona picker —
@@ -1729,7 +1732,11 @@ async function runInteractive(
       personaSource: options.personaSource,
       cwd,
       noLaunchMetadata: options.noLaunchMetadata,
-      env: process.env
+      env: process.env,
+      // Launch metadata ingest runs in the background while the user is reading
+      // persona output; route its warnings to the CLI log file rather than the
+      // terminal so a transient backend hiccup doesn't surface as scary noise.
+      onWarn: (msg) => launchMetadataLog.warn(msg)
     });
 
   const inputEnv = inputResolution.values;
diff --git a/packages/cli/src/logger.ts b/packages/cli/src/logger.ts
new file mode 100644
index 00000000..0e7e542f
--- /dev/null
+++ b/packages/cli/src/logger.ts
@@ -0,0 +1,140 @@
+/**
+ * Lightweight file logger for the AgentWorkforce CLI.
+ *
+ * Modeled on Agent Relay's logger (relay/packages/utils/src/logger.ts):
+ * - Writes structured lines to a log file so diagnostics never pollute the
+ *   terminal the user is staring at while a persona launches.
+ * - Configurable via environment variables, read at call time for late binding.
+ * - No external dependencies.
+ *
+ * Default log file: `<workforce home>/logs/cli.log`
+ *   (i.e. `~/.agentworkforce/workforce/logs/cli.log`).
+ * Overrides:
+ *   AGENTWORKFORCE_LOG_FILE   absolute path to the log file ('' or '-' → stderr)
+ *   AGENTWORKFORCE_LOG_LEVEL  DEBUG | INFO | WARN | ERROR (default INFO)
+ *   AGENTWORKFORCE_LOG_JSON   '1' to emit JSON lines instead of text
+ */
+
+import fs from 'node:fs';
+import path from 'node:path';
+
+import { defaultWorkforceHomeDir } from './local-personas.js';
+
+export type LogLevel = 'DEBUG' | 'INFO' | 'WARN' | 'ERROR';
+
+interface LogEntry {
+  ts: string;
+  level: LogLevel;
+  component: string;
+  msg: string;
+  [key: string]: unknown;
+}
+
+const LEVEL_PRIORITY: Record<LogLevel, number> = {
+  DEBUG: 0,
+  INFO: 1,
+  WARN: 2,
+  ERROR: 3
+};
+
+function defaultLogFile(): string {
+  return path.join(defaultWorkforceHomeDir(), 'logs', 'cli.log');
+}
+
+/**
+ * Resolve the log destination. Returns `undefined` when the user has opted to
+ * send logs to stderr (`AGENTWORKFORCE_LOG_FILE` set to '' or '-').
+ */
+function getLogFile(): string | undefined {
+  const override = process.env.AGENTWORKFORCE_LOG_FILE;
+  if (override === undefined) return defaultLogFile();
+  const trimmed = override.trim();
+  if (trimmed === '' || trimmed === '-') return undefined;
+  return trimmed;
+}
+
+function getLogLevel(): LogLevel {
+  return (process.env.AGENTWORKFORCE_LOG_LEVEL ?? 'INFO').toUpperCase() as LogLevel;
+}
+
+function isLogJson(): boolean {
+  return process.env.AGENTWORKFORCE_LOG_JSON === '1';
+}
+
+// Track which log directories we've already created so we don't stat per write.
+const createdLogDirs = new Set<string>();
+
+function ensureLogDir(logFile: string): void {
+  const logDir = path.dirname(logFile);
+  if (!createdLogDirs.has(logDir) && !fs.existsSync(logDir)) {
+    fs.mkdirSync(logDir, { recursive: true });
+    createdLogDirs.add(logDir);
+  }
+}
+
+function shouldLog(level: LogLevel): boolean {
+  return LEVEL_PRIORITY[level] >= (LEVEL_PRIORITY[getLogLevel()] ?? LEVEL_PRIORITY.INFO);
+}
+
+function formatMessage(entry: LogEntry): string {
+  if (isLogJson()) {
+    return JSON.stringify(entry);
+  }
+  const { ts, level, component, msg, ...extra } = entry;
+  const extraStr =
+    Object.keys(extra).length > 0
+      ? ' ' +
+        Object.entries(extra)
+          .map(([k, v]) => `${k}=${v}`)
+          .join(' ')
+      : '';
+  return `${ts} [${level}] [${component}] ${msg}${extraStr}`;
+}
+
+function log(level: LogLevel, component: string, msg: string, extra?: Record<string, unknown>): void {
+  if (!shouldLog(level)) return;
+
+  const entry: LogEntry = {
+    ts: new Date().toISOString(),
+    level,
+    component,
+    msg,
+    ...extra
+  };
+
+  const formatted = formatMessage(entry);
+
+  const logFile = getLogFile();
+  if (logFile) {
+    try {
+      ensureLogDir(logFile);
+      fs.appendFileSync(logFile, formatted + '\n');
+      return;
+    } catch {
+      // Fall through to stderr if the log file is unwritable — never throw
+      // from a logging call.
+    }
+  }
+
+  // No log file configured (or it failed): fall back to stderr so the
+  // diagnostic isn't lost entirely. We never write to stdout.
+  process.stderr.write(formatted + '\n');
+}
+
+/**
+ * Create a logger for a specific component.
+ * @param component - Component name (e.g. 'launch-metadata', 'persona-install').
+ */
+export function createLogger(component: string) {
+  return {
+    debug: (msg: string, extra?: Record<string, unknown>) => log('DEBUG', component, msg, extra),
+    info: (msg: string, extra?: Record<string, unknown>) => log('INFO', component, msg, extra),
+    warn: (msg: string, extra?: Record<string, unknown>) => log('WARN', component, msg, extra),
+    error: (msg: string, extra?: Record<string, unknown>) => log('ERROR', component, msg, extra)
+  };
+}
+
+/** Absolute path of the active log file, or `undefined` when logging to stderr. */
+export function activeLogFile(): string | undefined {
+  return getLogFile();
+}