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---
name: ai-sdk-ui
description: |
Build React chat interfaces with Vercel AI SDK v5/v6. Covers v6 beta (agent integration, tool approval,
auto-submit), v4→v5 migration (breaking changes), useChat/useCompletion/useObject/useAssistant hooks,
and 12 UI error solutions (stream parsing, stale body values, React update depth).
Use when: implementing AI SDK v5/v6 chat UIs, migrating v4→v5, troubleshooting "useChat failed to parse
stream", "useChat no response", or "stale body values" errors, or integrating OpenAI assistants.
license: MIT
metadata:
version: 1.1.0
last_verified: 2025-11-22
ai_sdk_version: 5.0.99 stable / 6.0.0-beta.108
breaking_changes: true (v4→v5 migration guide included)
production_tested: true
keywords:
- ai sdk ui
- ai sdk v6 beta
- ai sdk 6
- vercel ai sdk ui
- useChat hook
- useCompletion hook
- useObject hook
- useAssistant hook
- react ai chat
- ai chat interface
- streaming ai ui
- nextjs ai chat
- react streaming
- ai sdk react
- agent integration
- tool approval workflow
- human in the loop ui
- chat message state
- ai file attachments
- message persistence
- useChat error
- streaming failed ui
- parse stream error
- useChat no response
- stale body values
- react maximum update depth
- react ai hooks
- nextjs app router ai
- nextjs pages router ai
- ai chat component
- streaming response react
- react ai completion
- openai assistant ui
---
# AI SDK UI - Frontend React Hooks
Frontend React hooks for AI-powered user interfaces with Vercel AI SDK v5/v6.
**Version**: AI SDK v5.0.99 (Stable) / v6.0.0-beta.108 (Beta)
**Framework**: React 18+, Next.js 14+
**Last Updated**: 2025-11-22
---
## AI SDK 6 Beta (November 2025)
**Status:** Beta (stable release planned end of 2025)
**Latest:** ai@6.0.0-beta.108 (Nov 22, 2025)
**Migration:** Minimal breaking changes from v5 → v6
### New UI Features in v6 Beta
**1. Agent Integration**
Type-safe messaging with agents using `InferAgentUIMessage<typeof agent>`:
```tsx
import { useChat } from '@ai-sdk/react';
import type { InferAgentUIMessage } from 'ai';
import { myAgent } from './agent';
export default function AgentChat() {
const { messages, sendMessage } = useChat<InferAgentUIMessage<typeof myAgent>>({
api: '/api/chat',
});
// messages are now type-checked against agent schema
}
```
**2. Tool Approval Workflows (Human-in-the-Loop)**
Request user confirmation before executing tools:
```tsx
import { useChat } from '@ai-sdk/react';
import { useState } from 'react';
export default function ChatWithApproval() {
const { messages, sendMessage, addToolApprovalResponse } = useChat({
api: '/api/chat',
});
const handleApprove = (toolCallId: string) => {
addToolApprovalResponse({
toolCallId,
approved: true, // or false to deny
});
};
return (
<div>
{messages.map(message => (
<div key={message.id}>
{message.toolInvocations?.map(tool => (
tool.state === 'awaiting-approval' && (
<div key={tool.toolCallId}>
<p>Approve tool call: {tool.toolName}?</p>
<button onClick={() => handleApprove(tool.toolCallId)}>
Approve
</button>
<button onClick={() => addToolApprovalResponse({
toolCallId: tool.toolCallId,
approved: false
})}>
Deny
</button>
</div>
)
))}
</div>
))}
</div>
);
}
```
**3. Auto-Submit Capability**
Automatically continue conversation after handling approvals:
```tsx
import { useChat, lastAssistantMessageIsCompleteWithApprovalResponses } from '@ai-sdk/react';
export default function AutoSubmitChat() {
const { messages, sendMessage } = useChat({
api: '/api/chat',
sendAutomaticallyWhen: lastAssistantMessageIsCompleteWithApprovalResponses,
// Automatically resubmit after all approval responses provided
});
}
```
**4. Structured Output in Chat**
Generate structured data alongside tool calling (previously only available in `useObject`):
```tsx
import { useChat } from '@ai-sdk/react';
import { z } from 'zod';
const schema = z.object({
summary: z.string(),
sentiment: z.enum(['positive', 'neutral', 'negative']),
});
export default function StructuredChat() {
const { messages, sendMessage } = useChat({
api: '/api/chat',
// Server can now stream structured output with chat messages
});
}
```
---
## useChat Hook - v4 → v5 Breaking Changes
**CRITICAL: useChat no longer manages input state in v5!**
**v4 (OLD - DON'T USE):**
```tsx
const { messages, input, handleInputChange, handleSubmit, append } = useChat();
<form onSubmit={handleSubmit}>
<input value={input} onChange={handleInputChange} />
</form>
```
**v5 (NEW - CORRECT):**
```tsx
const { messages, sendMessage } = useChat();
const [input, setInput] = useState('');
<form onSubmit={(e) => {
e.preventDefault();
sendMessage({ content: input });
setInput('');
}}>
<input value={input} onChange={(e) => setInput(e.target.value)} />
</form>
```
**Summary of v5 Changes:**
1. **Input management removed**: `input`, `handleInputChange`, `handleSubmit` no longer exist
2. **`append()``sendMessage()`**: New method for sending messages
3. **`onResponse` removed**: Use `onFinish` instead
4. **`initialMessages` → controlled mode**: Use `messages` prop for full control
5. **`maxSteps` removed**: Handle on server-side only
See `references/use-chat-migration.md` for complete migration guide.
---
## useAssistant Hook
Interact with OpenAI-compatible assistant APIs with automatic UI state management.
**Import:**
```tsx
import { useAssistant } from '@ai-sdk/react';
```
**Basic Usage:**
```tsx
'use client';
import { useAssistant } from '@ai-sdk/react';
import { useState, FormEvent } from 'react';
export default function AssistantChat() {
const { messages, sendMessage, isLoading, error } = useAssistant({
api: '/api/assistant',
});
const [input, setInput] = useState('');
const handleSubmit = (e: FormEvent) => {
e.preventDefault();
sendMessage({ content: input });
setInput('');
};
return (
<div>
{messages.map(m => (
<div key={m.id}>
<strong>{m.role}:</strong> {m.content}
</div>
))}
<form onSubmit={handleSubmit}>
<input
value={input}
onChange={(e) => setInput(e.target.value)}
disabled={isLoading}
/>
</form>
{error && <div>{error.message}</div>}
</div>
);
}
```
**Use Cases:**
- Building OpenAI Assistant-powered UIs
- Managing assistant threads and runs
- Streaming assistant responses with UI state management
- File search and code interpreter integrations
See official docs for complete API reference: https://ai-sdk.dev/docs/reference/ai-sdk-ui/use-assistant
---
## Top UI Errors & Solutions
See `references/top-ui-errors.md` for complete documentation. Quick reference:
### 1. useChat Failed to Parse Stream
**Error**: `SyntaxError: Unexpected token in JSON at position X`
**Cause**: API route not returning proper stream format.
**Solution**:
```typescript
// ✅ CORRECT
return result.toDataStreamResponse();
// ❌ WRONG
return new Response(result.textStream);
```
### 2. useChat No Response
**Cause**: API route not streaming correctly.
**Solution**:
```typescript
// App Router - use toDataStreamResponse()
export async function POST(req: Request) {
const result = streamText({ /* ... */ });
return result.toDataStreamResponse(); // ✅
}
// Pages Router - use pipeDataStreamToResponse()
export default async function handler(req, res) {
const result = streamText({ /* ... */ });
return result.pipeDataStreamToResponse(res); // ✅
}
```
### 3. Streaming Not Working When Deployed
**Cause**: Deployment platform buffering responses.
**Solution**: Vercel auto-detects streaming. Other platforms may need configuration.
### 4. Stale Body Values with useChat
**Cause**: `body` option captured at first render only.
**Solution**:
```typescript
// ❌ WRONG - body captured once
const { userId } = useUser();
const { messages } = useChat({
body: { userId }, // Stale!
});
// ✅ CORRECT - use controlled mode
const { userId } = useUser();
const { messages, sendMessage } = useChat();
sendMessage({
content: input,
data: { userId }, // Fresh on each send
});
```
### 5. React Maximum Update Depth
**Cause**: Infinite loop in useEffect.
**Solution**:
```typescript
// ❌ WRONG
useEffect(() => {
saveMessages(messages);
}, [messages, saveMessages]); // saveMessages triggers re-render!
// ✅ CORRECT
useEffect(() => {
saveMessages(messages);
}, [messages]); // Only depend on messages
```
See `references/top-ui-errors.md` for 7 more common errors.
---
## Streaming Best Practices
### Performance
**Always use streaming for better UX:**
```tsx
// ✅ GOOD - Streaming (shows tokens as they arrive)
const { messages } = useChat({ api: '/api/chat' });
// ❌ BAD - Non-streaming (user waits for full response)
const response = await fetch('/api/chat', { method: 'POST' });
```
### UX Patterns
**Show loading states:**
```tsx
{isLoading && <div>AI is typing...</div>}
```
**Provide stop button:**
```tsx
{isLoading && <button onClick={stop}>Stop</button>}
```
**Auto-scroll to latest message:**
```tsx
useEffect(() => {
messagesEndRef.current?.scrollIntoView({ behavior: 'smooth' });
}, [messages]);
```
**Disable input while loading:**
```tsx
<input disabled={isLoading} />
```
See `references/streaming-patterns.md` for comprehensive best practices.
---
## When to Use This Skill
### Use ai-sdk-ui When:
- Building React chat interfaces
- Implementing AI completions in UI
- Streaming AI responses to frontend
- Building Next.js AI applications
- Handling chat message state
- Displaying tool calls in UI
- Managing file attachments with AI
- Migrating from v4 to v5 (UI hooks)
- Encountering useChat/useCompletion errors
### Don't Use When:
- Need backend AI functionality → Use **ai-sdk-core** instead
- Building non-React frontends (Svelte, Vue) → Check official docs
- Need Generative UI / RSC → See https://ai-sdk.dev/docs/ai-sdk-rsc
- Building native apps → Different SDK required
### Related Skills:
- **ai-sdk-core** - Backend text generation, structured output, tools, agents
- Compose both for full-stack AI applications
---
## Package Versions
**Stable (v5):**
```json
{
"dependencies": {
"ai": "^5.0.99",
"@ai-sdk/react": "^1.0.0",
"@ai-sdk/openai": "^2.0.68",
"react": "^18.2.0",
"zod": "^3.23.8"
}
}
```
**Beta (v6):**
```json
{
"dependencies": {
"ai": "6.0.0-beta.108",
"@ai-sdk/react": "beta",
"@ai-sdk/openai": "beta"
}
}
```
**Version Notes:**
- AI SDK v5.0.99 (stable, Nov 2025)
- AI SDK v6.0.0-beta.108 (beta, Nov 22, 2025) - minimal breaking changes
- React 18+ (React 19 supported)
- Next.js 14+ recommended (13.4+ works)
- Zod 3.23.8+ for schema validation
---
## Links to Official Documentation
**Core UI Hooks:**
- AI SDK UI Overview: https://ai-sdk.dev/docs/ai-sdk-ui/overview
- useChat: https://ai-sdk.dev/docs/ai-sdk-ui/chatbot
- useCompletion: https://ai-sdk.dev/docs/ai-sdk-ui/completion
- useObject: https://ai-sdk.dev/docs/ai-sdk-ui/object-generation
**Advanced Topics (Link Only):**
- Generative UI (RSC): https://ai-sdk.dev/docs/ai-sdk-rsc/overview
- Stream Protocols: https://ai-sdk.dev/docs/ai-sdk-ui/stream-protocols
- Message Metadata: https://ai-sdk.dev/docs/ai-sdk-ui/message-metadata
**Next.js Integration:**
- Next.js App Router: https://ai-sdk.dev/docs/getting-started/nextjs-app-router
- Next.js Pages Router: https://ai-sdk.dev/docs/getting-started/nextjs-pages-router
**Migration & Troubleshooting:**
- v4→v5 Migration: https://ai-sdk.dev/docs/migration-guides/migration-guide-5-0
- Troubleshooting: https://ai-sdk.dev/docs/troubleshooting
- Common Issues: https://ai-sdk.dev/docs/troubleshooting/common-issues
**Vercel Deployment:**
- Vercel Functions: https://vercel.com/docs/functions
- Streaming on Vercel: https://vercel.com/docs/functions/streaming
---
## Templates
This skill includes the following templates in `templates/`:
1. **use-chat-basic.tsx** - Basic chat with manual input (v5 pattern)
2. **use-chat-tools.tsx** - Chat with tool calling UI rendering
3. **use-chat-attachments.tsx** - File attachments support
4. **use-completion-basic.tsx** - Basic text completion
5. **use-object-streaming.tsx** - Streaming structured data
6. **nextjs-chat-app-router.tsx** - Next.js App Router complete example
7. **nextjs-chat-pages-router.tsx** - Next.js Pages Router complete example
8. **nextjs-api-route.ts** - API route for both App and Pages Router
9. **message-persistence.tsx** - Save/load chat history
10. **custom-message-renderer.tsx** - Custom message components with markdown
11. **package.json** - Dependencies template
## Reference Documents
See `references/` for:
- **use-chat-migration.md** - Complete v4→v5 migration guide
- **streaming-patterns.md** - UI streaming best practices
- **top-ui-errors.md** - 12 common UI errors with solutions
- **nextjs-integration.md** - Next.js setup patterns
- **links-to-official-docs.md** - Organized links to official docs
---
**Production Tested**: WordPress Auditor (https://wordpress-auditor.webfonts.workers.dev)
**Last Updated**: 2025-11-22