ai-sdk-6

AI SDK 6 maintenance

Apply this skill only to ai@6 projects. Resolve compatible provider and UI packages from the existing manifest/lockfile. Use ai-sdk when the major is unknown and ai-sdk-7 for an authorized upgrade.

Read the resolved ai/docs/, provider docs and source/types for the exact minor release. In a monorepo, resolve from the app using the dependency. Default web docs and repository main can describe v7. ai bundles docs/ from 6.0.32; the tree mirrors the website paths (mapping in ai-sdk). If installed docs are unavailable, select the ai@<resolved-version> tag in vercel/ai and read content/docs/. Feature links here use a checked v6 documentation snapshot as a fallback; match the project's release when available. This tag selects documentation, not an application dependency version.

Boundaries that differ from old and new code

• Text functions use system; ToolLoopAgent uses instructions.
• Loop limits use stopWhen: stepCountIs(...). Text functions default to one step (tool execution without a follow-up answer); ToolLoopAgent defaults to 20.
• convertToModelMessages is async; await it.
• Use text functions with Output for new schema output; legacy object functions are deprecated.
• Tools use inputSchema; SDK-executed approval is tool-level needsApproval. V6 does not know v7's toolApproval: unless a typecheck rejects it, it is ignored and the tool runs without approval.
• React useChat owns messages and stream status, not form input. Use the appropriate transport and UI-message response protocol.
• Core completion callbacks are onFinish; result usage is final-step usage, while totalUsage covers all steps.

Use a configured model verified for the actual provider. Typecheck and test a multi-turn stream with relevant tool/approval/error states after integration changes.

Core shape

Checked with ai@6.0.298, @ai-sdk/react@3.0.301, zod@4.6.5, React 19 and TypeScript 5.9: tsc --noEmit, plus a mock-model run through one tool step and the follow-up answer. A string model resolves through the AI Gateway. In v7, system, stepCountIs and result.toUIMessageStreamResponse() become instructions, isStepCount and createUIMessageStreamResponse({ stream: toUIMessageStream({ stream: result.stream }) }).

// app/api/chat/route.ts
import { convertToModelMessages, stepCountIs, streamText, tool, validateUIMessages,
  type InferUITools, type UIDataTypes, type UIMessage } from 'ai';
import { z } from 'zod';

const tools = {
  weather: tool({
    inputSchema: z.object({ city: z.string() }),
    execute: async ({ city }) => ({ city, celsius: 21 }),
  }),
};
export type ChatMessage = UIMessage<never, UIDataTypes, InferUITools<typeof tools>>;

export async function POST(req: Request) {
  const { messages } = await req.json();
  const uiMessages = await validateUIMessages<ChatMessage>({ messages, tools });
  const result = streamText({
    model: 'provider/model-id', // configured gateway ID, or a provider instance
    system: 'Answer briefly.',
    messages: await convertToModelMessages(uiMessages),
    tools,
    stopWhen: stepCountIs(5),
  });
  return result.toUIMessageStreamResponse();
}

// app/page.tsx
'use client';
import { useChat } from '@ai-sdk/react';
import { DefaultChatTransport } from 'ai';
import type { ChatMessage } from './api/chat/route';

const transport = new DefaultChatTransport<ChatMessage>({ api: '/api/chat' });

export default function Chat() {
  const { messages, sendMessage, status } = useChat<ChatMessage>({ transport });
  return (
    <form action={(form) => void sendMessage({ text: String(form.get('text')) })}>
      {messages.map((m) => <div key={m.id}>{m.parts.map((part, i) =>
        part.type === 'text' ? <p key={i}>{part.text}</p>
        : part.type === 'tool-weather' && part.state === 'output-available'
          ? <p key={i}>{part.output.city}: {part.output.celsius} °C</p> : null)}</div>)}
      <input name="text" disabled={status === 'submitted' || status === 'streaming'} />
    </form>
  );
}

Read for the feature

• Agents: loop limits, call options and context.
• Core functions: output and stream contracts.
• Tools: execution, approval and typed states.
• UI hooks: transport, restoration and stream lifetime.
• Middleware: provider interception.
• MCP: transport and cleanup.
• Workflows: when a loop needs explicit orchestration.
• Examples: version-matched official implementations.