feat(core): increase fetch timeout and fix [object Object] error stringification (#20441)

Co-authored-by: Gal Zahavi <38544478+galz10@users.noreply.github.com>

packages/core/src/code_assist/server.test.ts

@@ -73,17 +73,19 @@ describe('CodeAssistServer', () => {
       LlmRole.MAIN,
     );
 
-    expect(mockRequest).toHaveBeenCalledWith({
-      url: expect.stringContaining(':generateContent'),
-      method: 'POST',
-      headers: {
-        'Content-Type': 'application/json',
-        'x-custom-header': 'test-value',
-      },
-      responseType: 'json',
-      body: expect.any(String),
-      signal: undefined,
-    });
+    expect(mockRequest).toHaveBeenCalledWith(
+      expect.objectContaining({
+        url: expect.stringContaining(':generateContent'),
+        method: 'POST',
+        headers: {
+          'Content-Type': 'application/json',
+          'x-custom-header': 'test-value',
+        },
+        responseType: 'json',
+        body: expect.any(String),
+        signal: undefined,
+      }),
+    );
 
     const requestBody = JSON.parse(mockRequest.mock.calls[0][0].body);
     expect(requestBody.user_prompt_id).toBe('user-prompt-id');
@@ -391,17 +393,19 @@ describe('CodeAssistServer', () => {
       results.push(res);
     }
 
-    expect(mockRequest).toHaveBeenCalledWith({
-      url: expect.stringContaining(':streamGenerateContent'),
-      method: 'POST',
-      params: { alt: 'sse' },
-      responseType: 'stream',
-      body: expect.any(String),
-      headers: {
-        'Content-Type': 'application/json',
-      },
-      signal: undefined,
-    });
+    expect(mockRequest).toHaveBeenCalledWith(
+      expect.objectContaining({
+        url: expect.stringContaining(':streamGenerateContent'),
+        method: 'POST',
+        params: { alt: 'sse' },
+        responseType: 'stream',
+        body: expect.any(String),
+        headers: {
+          'Content-Type': 'application/json',
+        },
+        signal: undefined,
+      }),
+    );
 
     expect(results).toHaveLength(2);
     expect(results[0].candidates?.[0].content?.parts?.[0].text).toBe('Hello');

packages/core/src/utils/errors.ts

@@ -29,6 +29,15 @@ export function getErrorMessage(error: unknown): string {
   if (friendlyError instanceof Error) {
     return friendlyError.message;
   }
+  if (
+    typeof friendlyError === 'object' &&
+    friendlyError !== null &&
+    'message' in friendlyError &&
+    typeof (friendlyError as { message: unknown }).message === 'string'
+  ) {
+    // eslint-disable-next-line @typescript-eslint/no-unsafe-type-assertion
+    return (friendlyError as { message: string }).message;
+  }
   try {
     return String(friendlyError);
   } catch {

packages/core/src/utils/errors_timeout.test.ts

@@ -0,0 +1,46 @@
+/**
+ * @license
+ * Copyright 2026 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { describe, it, expect } from 'vitest';
+import { getErrorMessage } from './errors.js';
+import { type HttpError } from './httpErrors.js';
+
+describe('getErrorMessage with timeout errors', () => {
+  it('should handle undici HeadersTimeoutError correctly', () => {
+    // Simulate what undici might throw if it's not a proper Error instance
+    // or has a specific code.
+    const timeoutError = {
+      name: 'HeadersTimeoutError',
+      code: 'UND_ERR_HEADERS_TIMEOUT',
+      message: 'Headers timeout error',
+    };
+
+    // If it's a plain object, getErrorMessage might struggle if it expects an Error
+    const message = getErrorMessage(timeoutError);
+    // Based on existing implementation:
+    // friendlyError = toFriendlyError(timeoutError) -> returns timeoutError
+    // if (friendlyError instanceof Error) -> false
+    // return String(friendlyError) -> "[object Object]"
+
+    expect(message).toBe('Headers timeout error');
+  });
+
+  it('should handle undici HeadersTimeoutError as an Error instance', () => {
+    const error = new Error('Headers timeout error');
+    (error as HttpError).name = 'HeadersTimeoutError';
+    (error as HttpError).status = 504; // simulate status for test
+    (error as HttpError & { code?: string }).code = 'UND_ERR_HEADERS_TIMEOUT';
+
+    const message = getErrorMessage(error);
+    expect(message).toBe('Headers timeout error');
+  });
+
+  it('should return String representation for objects without a message property', () => {
+    const error = { some: 'other', object: 123 };
+    const message = getErrorMessage(error);
+    expect(message).toBe('[object Object]');
+  });
+});

packages/core/src/utils/fetch.ts

@@ -6,7 +6,18 @@
 
 import { getErrorMessage, isNodeError } from './errors.js';
 import { URL } from 'node:url';
-import { ProxyAgent, setGlobalDispatcher } from 'undici';
+import { Agent, ProxyAgent, setGlobalDispatcher } from 'undici';
+
+const DEFAULT_HEADERS_TIMEOUT = 60000; // 60 seconds
+const DEFAULT_BODY_TIMEOUT = 300000; // 5 minutes
+
+// Configure default global dispatcher with higher timeouts
+setGlobalDispatcher(
+  new Agent({
+    headersTimeout: DEFAULT_HEADERS_TIMEOUT,
+    bodyTimeout: DEFAULT_BODY_TIMEOUT,
+  }),
+);
 
 const PRIVATE_IP_RANGES = [
   /^10\./,
@@ -73,5 +84,11 @@ export async function fetchWithTimeout(
 }
 
 export function setGlobalProxy(proxy: string) {
-  setGlobalDispatcher(new ProxyAgent(proxy));
+  setGlobalDispatcher(
+    new ProxyAgent({
+      uri: proxy,
+      headersTimeout: DEFAULT_HEADERS_TIMEOUT,
+      bodyTimeout: DEFAULT_BODY_TIMEOUT,
+    }),
+  );
 }