Improve SDK error handling and CLI network error display

- Sanitize SDK error messages to remove unhelpful system messages
- Increase default stream timeout from 15s to 3 minutes
- Move offline banner to top of chat interface for better visibility
- Add comprehensive error handling tests for SDK

Author: brandonkachen

cli/src/chat.tsx

@@ -579,9 +579,8 @@ export const Chat = ({
   })
 
   const offlineBannerMessage = useMemo(() => {
-    const baseMessage = `⚠️ Network Error: ${
-      networkStatus.error?.message ?? 'Connection lost'
-    }`
+    const errorMessage = networkStatus.error?.message ?? 'Connection lost'
+    const baseMessage = `⚠️ ${errorMessage}`
     const retryMessage =
       pendingRetryCount > 0
         ? ` • ${pendingRetryCount} message${
@@ -921,6 +920,31 @@ export const Chat = ({
         flexGrow: 1,
       }}
     >
+      {!networkStatus.isOnline && (
+        <box
+          style={{
+            flexDirection: 'column',
+            flexShrink: 0,
+            width: '100%',
+            paddingTop: 1,
+            paddingBottom: 1,
+            paddingLeft: 1,
+            paddingRight: 1,
+            backgroundColor: theme.surface ?? theme.background ?? '#333333',
+          }}
+        >
+          <text
+            style={{
+              fg: theme.warning ?? theme.foreground,
+              wrapMode: 'word',
+              width: '100%',
+            }}
+          >
+            {offlineBannerMessage}
+          </text>
+        </box>
+      )}
+
       <scrollbox
         ref={scrollRef}
         stickyScroll
@@ -1096,28 +1120,6 @@ export const Chat = ({
       </box>
 
       {validationBanner}
-
-      {!networkStatus.isOnline && (
-        <box
-          style={{
-            width: '100%',
-            paddingTop: 1,
-            paddingBottom: 1,
-            paddingLeft: 1,
-            paddingRight: 1,
-            backgroundColor: theme.surface ?? theme.background ?? '#333333',
-          }}
-        >
-          <text
-            style={{
-              fg: theme.warning ?? theme.foreground,
-              wrapMode: 'word',
-            }}
-          >
-            {offlineBannerMessage}
-          </text>
-        </box>
-      )}
     </box>
   )
 }

sdk/src/__tests__/abort-controller.test.ts

@@ -66,13 +66,13 @@ describe('Abort Controller - Single Controller Architecture', () => {
       expect(client.options.streamTimeoutMs).toBe(30000)
     })
 
-    test('streamTimeoutMs defaults to 15000ms', () => {
+    test('streamTimeoutMs defaults to 180000ms (3 minutes)', () => {
       const client = new CodebuffClient({
         apiKey: 'test-key',
         disableConsoleErrors: true,
       })
 
-      expect(client.options.streamTimeoutMs).toBe(15000)
+      expect(client.options.streamTimeoutMs).toBe(180000)
     })
   })
 

sdk/src/__tests__/errors.test.ts

@@ -0,0 +1,68 @@
+import { describe, expect, test } from 'bun:test'
+import { NetworkError, AuthenticationError, isNetworkError, isAuthenticationError } from '../errors'
+
+describe('NetworkError', () => {
+  test('removes unhelpful browser error messages', () => {
+    const error = new NetworkError('Is the computer able to access the url?')
+    expect(error.message).toBe('')
+  })
+
+  test('removes unhelpful text but preserves the rest', () => {
+    const error = new NetworkError('Network error: Is the computer able to access the url?')
+    expect(error.message).toBe('Network error:')
+  })
+
+  test('removes unhelpful text from middle of message', () => {
+    const error = new NetworkError('Unable to connect. Is the computer able to access the url? Verify connection.')
+    expect(error.message).toBe('Unable to connect. Verify connection.')
+  })
+
+  test('preserves helpful error messages', () => {
+    const error = new NetworkError('Connection refused')
+    expect(error.message).toBe('Connection refused')
+  })
+
+  test('includes error code', () => {
+    const error = new NetworkError('Test error')
+    expect(error.code).toBe('NETWORK_ERROR')
+  })
+
+  test('includes status when provided', () => {
+    const error = new NetworkError('Server error', { status: 500 })
+    expect(error.status).toBe(500)
+  })
+
+  test('includes originalError when provided', () => {
+    const originalError = new Error('Original')
+    const error = new NetworkError('Wrapped error', { originalError })
+    expect(error.originalError).toBe(originalError)
+  })
+
+  test('includes streamTimedOut flag when provided', () => {
+    const error = new NetworkError('Timeout', { streamTimedOut: true })
+    expect(error.streamTimedOut).toBe(true)
+  })
+})
+
+describe('AuthenticationError', () => {
+  test('creates error with status', () => {
+    const error = new AuthenticationError('Auth failed', 401)
+    expect(error.message).toBe('Auth failed')
+    expect(error.status).toBe(401)
+    expect(error.code).toBe('AUTH_FAILED')
+  })
+})
+
+describe('Type guards', () => {
+  test('isNetworkError identifies NetworkError instances', () => {
+    const error = new NetworkError('Test')
+    expect(isNetworkError(error)).toBe(true)
+    expect(isNetworkError(new Error('Test'))).toBe(false)
+  })
+
+  test('isAuthenticationError identifies AuthenticationError instances', () => {
+    const error = new AuthenticationError('Test', 401)
+    expect(isAuthenticationError(error)).toBe(true)
+    expect(isAuthenticationError(new Error('Test'))).toBe(false)
+  })
+})

sdk/src/client.ts

@@ -35,7 +35,7 @@ export class CodebuffClient {
     const fingerprintId =
       options.fingerprintId ??
       `codebuff-sdk-${Math.random().toString(36).substring(2, 15)}`
-    const streamTimeoutMs = options.streamTimeoutMs ?? 15_000
+    const streamTimeoutMs = options.streamTimeoutMs ?? 180_000 // 3 minutes
 
     this.options = {
       apiKey: foundApiKey,

sdk/src/errors.ts

@@ -2,6 +2,14 @@
  * Custom error classes for the SDK
  */
 
+/**
+ * Sanitizes error messages by removing unhelpful system messages
+ */
+function sanitizeErrorMessage(message: string): string {
+  // Remove unhelpful browser/system error message
+  return message.replace(/Is the computer able to access the url\?\s*/g, '').trim()
+}
+
 export interface ErrorWithCode extends Error {
   code: string
 }
@@ -44,7 +52,7 @@ export class NetworkError extends Error implements NetworkErrorDetails {
     message: string,
     options?: { status?: number; originalError?: any; streamTimedOut?: boolean },
   ) {
-    super(message)
+    super(sanitizeErrorMessage(message))
     this.name = 'NetworkError'
     this.status = options?.status
     this.originalError = options?.originalError

sdk/src/run.ts

@@ -118,7 +118,7 @@ export async function run({
   agentDefinitions,
   maxAgentSteps = MAX_AGENT_STEPS_DEFAULT,
   env,
-  streamTimeoutMs = 15_000,
+  streamTimeoutMs = 180_000, // 3 minutes
 
   handleEvent,
   handleStreamChunk,