fix(cli): render non-Error failures instead of [object Object]

CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- A CLI failure raised as a non-`Error` value — e.g. a protocol-shaped `{ status: 401 }` rejection from a broker client — now prints its message, status, and code instead of `[object Object]`, and an `Error` with an empty message no longer exits silently with no output at all. The top-level handler, the `node agent attach` paths, and the broker failure mapper share the formatter, which redacts credentials in the values it serializes.
 - `agent-relay integration webhook create` now works. It took a `<url>` argument and sent `{ url, event }`, but `POST /v1/webhooks` accepts `{ channel, name? }` and returns the URL — so every invocation failed with `channel is required`. It now takes `<channel>` with an optional `--name`, matching `create-inbound`, which posts to the same endpoint.
 - `@agent-relay/sdk` `RelayCreateWebhookInput` declared a required `url` and an `event`, neither of which the endpoint accepts. It is now `{ channel, name? }`. Code passing `url`/`event` was already failing at runtime.
 

packages/cli/src/cli/index.ts

@@ -7,6 +7,7 @@ import { fileURLToPath } from 'node:url';
 import { runAiSdkSidecarMain } from '@agent-relay/harnesses';
 
 import { runCli } from './bootstrap.js';
+import { describeError } from './lib/describe-error.js';
 
 export * from './bootstrap.js';
 
@@ -25,10 +26,9 @@ if (isEntrypoint()) {
   main.catch((err) => {
     // Commander will have already printed a helpful message for parse errors.
     // For other top-level failures, surface them to stderr and exit non-zero.
-    const message = err instanceof Error ? err.message : String(err);
-    if (message) {
-      process.stderr.write(`${message}\n`);
-    }
+    // `describeError` keeps a non-Error rejection (e.g. `{ status: 401 }` from
+    // a broker client) readable instead of collapsing it to `[object Object]`.
+    process.stderr.write(`${describeError(err)}\n`);
     process.exit(1);
   });
 }

packages/cli/src/cli/lib/attach-broker.ts

@@ -1,6 +1,7 @@
 import { HarnessDriverClient } from '@agent-relay/harness-driver';
 
 import type { BrokerConnection } from './broker-connection.js';
+import { describeError } from './describe-error.js';
 
 export type {
   InboundDeliveryMode,
@@ -40,5 +41,5 @@ export function mapBrokerSdkFailure(error: unknown): BrokerSdkFailure {
     typeof (error as { status: unknown }).status === 'number'
       ? (error as { status: number }).status
       : 0;
-  return { status, message: error instanceof Error ? error.message : String(error) };
+  return { status, message: describeError(error) };
 }

packages/cli/src/cli/lib/attach-drive.ts

@@ -86,6 +86,7 @@ import {
   type PtyInputStreamOptions,
   type PtyInputWriteResult,
 } from '../lib/attach-broker.js';
+import { describeError } from './describe-error.js';
 import { createPredictiveEcho, type CreatePredictiveEchoOptions } from './predictive-echo-screen.js';
 import type { PredictiveEcho } from '@agent-relay/harness-driver';
 
@@ -926,7 +927,7 @@ function runDriveSessionLoop(state: DriveSessionState, deps: DriveDependencies):
           // event loop on every keystroke.
           void stream.send(decoded).catch((err: unknown) => {
             if (settled) return;
-            const message = err instanceof Error ? err.message : String(err);
+            const message = describeError(err);
             deps.log(`[drive] input stream send failed: ${message}`);
             // The keystroke never reached the PTY — drop any optimistic echo
             // for it so the screen doesn't show input the agent didn't get.
@@ -1126,7 +1127,7 @@ function runDriveSessionLoop(state: DriveSessionState, deps: DriveDependencies):
         }
       } catch (err: unknown) {
         if (settled) return;
-        const message = err instanceof Error ? err.message : String(err);
+        const message = describeError(err);
         deps.error(`[drive] could not open PTY input stream: ${message}`);
         finish(1);
       }
@@ -1163,7 +1164,7 @@ function runDriveSessionLoop(state: DriveSessionState, deps: DriveDependencies):
         }
       } catch (err: unknown) {
         if (settled) return;
-        const message = err instanceof Error ? err.message : String(err);
+        const message = describeError(err);
         deps.error(`[drive] could not take terminal input: ${message}`);
         finish(1);
       }
@@ -1214,7 +1215,7 @@ function runDriveSessionLoop(state: DriveSessionState, deps: DriveDependencies):
         try {
           await predictiveEcho.seed(snapshotBytes);
         } catch (err: unknown) {
-          const message = err instanceof Error ? err.message : String(err);
+          const message = describeError(err);
           deps.log(`[drive] could not seed predictive echo: ${message}`);
           finish(1);
           return;

packages/cli/src/cli/lib/attach-native.ts

@@ -16,6 +16,7 @@ import {
   type BrokerConnection,
 } from './broker-connection.js';
 import { createBrokerClient } from './attach-broker.js';
+import { describeError } from './describe-error.js';
 
 export type NativeAttachMode = 'view' | 'drive' | 'passthrough';
 
@@ -146,7 +147,7 @@ export async function attachNative(
   try {
     brokerCursor = await client.currentEventSeq();
   } catch (error) {
-    deps.output.stderr(`Error: ${error instanceof Error ? error.message : String(error)}\n`);
+    deps.output.stderr(`Error: ${describeError(error)}\n`);
     client.disconnect();
     return 1;
   }
@@ -255,7 +256,7 @@ export async function attachNative(
             }
           })
           .catch((error: unknown) => {
-            deps.output.stderr(`Input failed: ${error instanceof Error ? error.message : String(error)}\n`);
+            deps.output.stderr(`Input failed: ${describeError(error)}\n`);
           })
           .then(() => undefined);
         commandChain = pendingCommand.catch(() => undefined);
@@ -279,7 +280,7 @@ export async function attachNative(
     await Promise.allSettled(pendingCommands);
     return 0;
   } catch (error) {
-    deps.output.stderr(`Error: ${error instanceof Error ? error.message : String(error)}\n`);
+    deps.output.stderr(`Error: ${describeError(error)}\n`);
     return 1;
   } finally {
     stopped = true;

packages/cli/src/cli/lib/attach-passthrough.ts

@@ -64,6 +64,7 @@ import {
   resizeWorker,
   type InboundDeliveryMode,
 } from './attach-drive.js';
+import { describeError } from './describe-error.js';
 import { createPredictiveEcho, type CreatePredictiveEchoOptions } from './predictive-echo-screen.js';
 import type { PredictiveEcho } from '@agent-relay/harness-driver';
 
@@ -560,7 +561,7 @@ export async function runPassthroughSession(
         if (decoded.length > 0) {
           void stream.send(decoded).catch((err: unknown) => {
             if (settled) return;
-            const message = err instanceof Error ? err.message : String(err);
+            const message = describeError(err);
             deps.log(`[passthrough] input stream send failed: ${message}`);
             // The keystroke never reached the PTY — drop any optimistic echo
             // for it so the screen doesn't show input the agent didn't get.
@@ -740,7 +741,7 @@ export async function runPassthroughSession(
         }
       } catch (err: unknown) {
         if (settled) return;
-        const message = err instanceof Error ? err.message : String(err);
+        const message = describeError(err);
         deps.error(`[passthrough] could not open PTY input stream: ${message}`);
         finish(1);
       }
@@ -775,7 +776,7 @@ export async function runPassthroughSession(
         }
       } catch (err: unknown) {
         if (settled) return;
-        const message = err instanceof Error ? err.message : String(err);
+        const message = describeError(err);
         deps.error(`[passthrough] could not take terminal input: ${message}`);
         finish(1);
       }
@@ -825,7 +826,7 @@ export async function runPassthroughSession(
         try {
           await predictiveEcho.seed(snapshotBytes);
         } catch (err: unknown) {
-          const message = err instanceof Error ? err.message : String(err);
+          const message = describeError(err);
           deps.log(`[passthrough] could not seed predictive echo: ${message}`);
           finish(1);
           return;

packages/cli/src/cli/lib/broker-lifecycle.test.ts

@@ -6,7 +6,7 @@ import { afterEach, describe, expect, it, vi } from 'vitest';
 import {
   classifyBrokerStartError,
   classifyBrokerStartStage,
-  describeError,
+  describeErrorWithCause,
   isBundledBunExecutableEntrypoint,
   readNodeDeliveryStatus,
   resolveNodeIdentityFromSession,
@@ -34,9 +34,9 @@ describe('isBundledBunExecutableEntrypoint', () => {
   });
 });
 
-describe('describeError', () => {
+describe('describeErrorWithCause', () => {
   it('returns plain message for a bare Error', () => {
-    expect(describeError(new Error('boom'))).toBe('boom');
+    expect(describeErrorWithCause(new Error('boom'))).toBe('boom');
   });
 
   it('unwraps the Node fetch failed cause and surfaces the network code', () => {
@@ -46,7 +46,7 @@ describe('describeError', () => {
     });
     const err = new TypeError('fetch failed', { cause });
 
-    const result = describeError(err);
+    const result = describeErrorWithCause(err);
     expect(result).toContain('fetch failed');
     expect(result).toContain('ECONNREFUSED');
     expect(result).toContain('127.0.0.1');
@@ -58,15 +58,15 @@ describe('describeError', () => {
     });
     const err = new TypeError('fetch failed', { cause });
 
-    const result = describeError(err);
+    const result = describeErrorWithCause(err);
     expect(result).toContain('ENOTFOUND');
     expect(result).toContain('agentrelay.com');
   });
 
   it('handles non-Error values without throwing', () => {
-    expect(describeError('something went wrong')).toBe('something went wrong');
-    expect(describeError(undefined)).toBe('undefined');
-    expect(describeError(null)).toBe('null');
+    expect(describeErrorWithCause('something went wrong')).toBe('something went wrong');
+    expect(describeErrorWithCause(undefined)).toBe('undefined');
+    expect(describeErrorWithCause(null)).toBe('null');
   });
 
   it('caps the cause-chain walk so a cycle cannot loop forever', () => {
@@ -75,7 +75,7 @@ describe('describeError', () => {
     a.cause = b;
     b.cause = a;
     // Just needs to terminate — the assertion is the absence of a hang.
-    expect(typeof describeError(a)).toBe('string');
+    expect(typeof describeErrorWithCause(a)).toBe('string');
   });
 });
 

packages/cli/src/cli/lib/broker-lifecycle.ts

@@ -21,6 +21,7 @@ import {
   type NodeDefinitionDescriptor,
   type RunningNodeProviderChild,
 } from './node-provider-child.js';
+import { describeError } from './describe-error.js';
 import { maskSecret } from './redact.js';
 import { startReflexCapture, type RunningReflexCapture } from './reflex-capture.js';
 import { projectWorkspaceKeyPath, writeProjectWorkspaceKey } from './project-workspace-key.js';
@@ -152,7 +153,7 @@ export function readBrokerConnection(dataDir: string): BrokerConnection | null {
 }
 
 function toErrorMessage(err: unknown): string {
-  return err instanceof Error ? err.message : String(err);
+  return describeError(err);
 }
 
 /** Emit a `[verbose]`-prefixed step marker via `deps.log` when `--verbose` is set. */
@@ -258,14 +259,17 @@ function errorCode(err: unknown): string | undefined {
 /**
  * Extract a human-meaningful detail string from an error, walking `err.cause`.
  *
+ * The broker-start specialization of {@link describeError}: it starts from the
+ * shared description and appends the cause chain's detail and error codes.
+ *
  * Node's native `fetch()` throws `TypeError: fetch failed` for any network
  * problem and stuffs the real reason (ECONNREFUSED, ENOTFOUND, AbortError,
  * UND_ERR_CONNECT_TIMEOUT, …) into `err.cause`. Without unwrapping, every
  * outbound HTTP failure looks identical to the user.
  *
  * Exported for testing.
  */
-export function describeError(err: unknown): string {
+export function describeErrorWithCause(err: unknown): string {
   const top = toErrorMessage(err);
   if (!(err instanceof Error) || !err.cause) return top;
 
@@ -1392,7 +1396,7 @@ export async function runUpCommand(options: UpOptions, deps: CoreDependencies):
         env: deps.env,
       });
     } catch (err: unknown) {
-      deps.error(`Failed to start broker in background: ${describeError(err)}`);
+      deps.error(`Failed to start broker in background: ${describeErrorWithCause(err)}`);
       deps.exit(1);
       return;
     }
@@ -1666,7 +1670,7 @@ export async function runUpCommand(options: UpOptions, deps: CoreDependencies):
     if (isBrokerAlreadyRunningError(message)) {
       reportAlreadyRunningError(message, paths.dataDir, deps);
     } else {
-      deps.error(`Failed to start broker: ${describeError(err)}`);
+      deps.error(`Failed to start broker: ${describeErrorWithCause(err)}`);
     }
     deps.exit(1);
   }

packages/cli/src/cli/lib/core-maintenance.ts

@@ -4,6 +4,7 @@ import path from 'node:path';
 import type { CoreDependencies, CoreFileSystem } from '../commands/core.js';
 import { track } from '../telemetry/index.js';
 import { readBrokerConnection } from './broker-lifecycle.js';
+import { describeError } from './describe-error.js';
 import { errorClassName } from './telemetry-helpers.js';
 
 const SNIPPET_MARKER_START_PREFIX = '<!-- prpm:snippet:start @agent-relay/agent-relay-snippet@';
@@ -17,7 +18,7 @@ const DEFAULT_ZED_SERVER_NAME = 'Agent Relay';
 const INSTALL_DIR_NAMES = ['.agentworkforce/relay', '.agent-relay'] as const;
 
 function toErrorMessage(err: unknown): string {
-  return err instanceof Error ? err.message : String(err);
+  return describeError(err);
 }
 
 /**

packages/cli/src/cli/lib/describe-error.test.ts

@@ -0,0 +1,64 @@
+import { describe, expect, it } from 'vitest';
+
+import { describeError } from './describe-error.js';
+
+describe('describeError', () => {
+  it('renders an Error as its message', () => {
+    expect(describeError(new Error('broker refused the attach'))).toBe('broker refused the attach');
+  });
+
+  it('falls back to name and cause when an Error has no message', () => {
+    expect(describeError(new Error(''))).toBe('Error');
+    const named = new Error('');
+    named.name = 'AttachError';
+    expect(describeError(named)).toBe('AttachError');
+    expect(describeError(new Error('', { cause: new Error('socket hang up') }))).toBe(
+      'Error: socket hang up'
+    );
+  });
+
+  it('keeps a protocol-shaped rejection readable instead of [object Object]', () => {
+    expect(describeError({ status: 401 })).toBe('{"status":401}');
+    expect(describeError({ status: 401, code: 'unauthorized', message: 'invalid workspace key' })).toBe(
+      'invalid workspace key (status 401, code unauthorized)'
+    );
+    expect(describeError({ error: 'invalid api key', status: 403 })).toBe('invalid api key (status 403)');
+  });
+
+  it('unwraps a nested error object', () => {
+    expect(describeError({ error: { message: 'node offline' }, code: 'node_unreachable' })).toBe(
+      'node offline (code node_unreachable)'
+    );
+  });
+
+  it('redacts credentials in the JSON fallback', () => {
+    const described = describeError({ status: 401, workspaceKey: 'rk_live_supersecret' });
+    expect(described).not.toContain('rk_live_supersecret');
+    expect(described).toContain('[redacted]');
+  });
+
+  it('tolerates cycles and truncates oversized payloads', () => {
+    const cyclic: Record<string, unknown> = { status: 500 };
+    cyclic.self = cyclic;
+    expect(describeError(cyclic)).toContain('[circular]');
+
+    const huge = describeError({ status: 500, blob: 'x'.repeat(5000) });
+    expect(huge.length).toBeLessThanOrEqual(501);
+    expect(huge.endsWith('…')).toBe(true);
+  });
+
+  it('renders primitives and empty values without going blank', () => {
+    expect(describeError('connection reset')).toBe('connection reset');
+    expect(describeError(404)).toBe('404');
+    expect(describeError(null)).toBe('null');
+    expect(describeError(undefined)).toBe('undefined');
+    expect(describeError('')).toBe('Unknown error');
+    expect(describeError({})).toBe('{}');
+  });
+
+  it('never returns the useless [object Object] rendering', () => {
+    for (const value of [{ status: 401 }, {}, Object.create(null), [{ status: 401 }]]) {
+      expect(describeError(value)).not.toBe('[object Object]');
+    }
+  });
+});