fix: Show friendly message in computer use cli when connection token is invalid (no-changelog) (#30288)

packages/@n8n/computer-use/src/cli.ts

@@ -5,13 +5,14 @@ import * as fs from 'node:fs/promises';
 
 import { isOriginAllowed, parseConfig } from './config';
 import { cliConfirmResourceAccess, sanitizeForTerminal } from './confirm-resource-cli';
-import { GatewayClient } from './gateway-client';
+import { GatewayAuthError, GatewayClient } from './gateway-client';
 import { GatewaySession } from './gateway-session';
 import {
 	configure,
 	logger,
 	printBanner,
 	printConnected,
+	printInvalidToken,
 	printModuleStatus,
 	printToolList,
 } from './logger';
@@ -223,7 +224,15 @@ async function main(
 	process.on('SIGINT', shutdown);
 	process.on('SIGTERM', shutdown);
 
-	await client.start();
+	try {
+		await client.start();
+	} catch (error) {
+		if (error instanceof GatewayAuthError) {
+			printInvalidToken(origin);
+			process.exit(1);
+		}
+		throw error;
+	}
 
 	printConnected(url);
 	printToolList(client.tools);

packages/@n8n/computer-use/src/gateway-client.test.ts

@@ -41,7 +41,7 @@ jest.mock('./tools/browser', () => ({
 }));
 
 import type { GatewayConfig } from './config';
-import { GatewayClient } from './gateway-client';
+import { GatewayAuthError, GatewayClient } from './gateway-client';
 import type { GatewaySession } from './gateway-session';
 import type { AffectedResource, ConfirmResourceAccess, ToolDefinition } from './tools/types';
 import { INSTANCE_RESOURCE_DECISION_KEYS } from './tools/types';
@@ -257,3 +257,65 @@ describe('GatewayClient.checkPermissions', () => {
 		});
 	});
 });
+
+describe('GatewayClient.uploadCapabilities', () => {
+	const originalFetch = global.fetch;
+
+	beforeEach(() => {
+		global.fetch = jest.fn();
+	});
+
+	afterEach(() => {
+		global.fetch = originalFetch;
+	});
+
+	function makeMinimalClient(): GatewayClient {
+		const client = new GatewayClient({
+			url: 'http://localhost:5678',
+			apiKey: 'tok',
+			config: makeConfig(),
+			session: makeSession(),
+			confirmResourceAccess: jest.fn(),
+		});
+
+		// Bypass tool discovery — uploadCapabilities only needs definitions to exist.
+		// @ts-expect-error — accessing private field for testing
+		client.allDefinitions = [];
+		// @ts-expect-error — accessing private field for testing
+		client.activeToolCategories = [];
+
+		return client;
+	}
+
+	function mockFetchResponse(status: number, body = ''): void {
+		(global.fetch as jest.Mock).mockResolvedValueOnce({
+			ok: status >= 200 && status < 300,
+			status,
+			text: jest.fn().mockResolvedValue(body),
+			json: jest.fn().mockResolvedValue({ data: { ok: true } }),
+		});
+	}
+
+	it('throws GatewayAuthError on 401', async () => {
+		mockFetchResponse(401, 'invalid token');
+		const client = makeMinimalClient();
+
+		await expect(client['uploadCapabilities']()).rejects.toBeInstanceOf(GatewayAuthError);
+	});
+
+	it('throws GatewayAuthError on 403', async () => {
+		mockFetchResponse(403, 'forbidden');
+		const client = makeMinimalClient();
+
+		await expect(client['uploadCapabilities']()).rejects.toBeInstanceOf(GatewayAuthError);
+	});
+
+	it('throws plain Error on non-auth failure (500)', async () => {
+		mockFetchResponse(500, 'server exploded');
+		const client = makeMinimalClient();
+
+		const promise = client['uploadCapabilities']();
+		await expect(promise).rejects.not.toBeInstanceOf(GatewayAuthError);
+		await expect(promise).rejects.toThrow(/Failed to upload capabilities: 500/);
+	});
+});

packages/@n8n/computer-use/src/gateway-client.ts

@@ -32,6 +32,17 @@ import { formatErrorResult } from './tools/utils';
 const MAX_RECONNECT_DELAY_MS = 30_000;
 const MAX_AUTH_RETRIES = 5;
 
+/** Thrown when the gateway rejects our pairing token with 401/403. */
+export class GatewayAuthError extends Error {
+	constructor(
+		readonly status: number,
+		readonly body: string,
+	) {
+		super(`Gateway rejected token: ${status} ${body}`);
+		this.name = 'GatewayAuthError';
+	}
+}
+
 /** Tag tool definitions with a category annotation (mutates in place for efficiency). */
 function tagCategory(defs: ToolDefinition[], category: string): ToolDefinition[] {
 	for (const def of defs) {
@@ -301,6 +312,9 @@ export class GatewayClient {
 
 		if (!response.ok) {
 			const text = await response.text();
+			if (response.status === 401 || response.status === 403) {
+				throw new GatewayAuthError(response.status, text);
+			}
 			throw new Error(`Failed to upload capabilities: ${response.status} ${text}`);
 		}
 

packages/@n8n/computer-use/src/logger.ts

@@ -259,6 +259,13 @@ export function printAuthFailure(): void {
 	logger.error(`  ${pc.red('✗')} Authentication failed — waiting for new pairing token`);
 }
 
+export function printInvalidToken(url: string): void {
+	logger.error(`  ${pc.red('✗')} Connection token invalid`);
+	logger.error(
+		`    ${pc.dim(`Go to ${url} and reconnect n8n Computer Use using a new connection token`)}`,
+	);
+}
+
 export function printReinitializing(): void {
 	logger.info(`  ${pc.magenta('▸')} Re-initializing gateway connection`);
 }