Vercel AI SDK 6 Beta (v6.ai-sdk.dev)

Vercel released AI SDK 6 in beta, introducing the v3 Language Model Specification that unlocks first-class agent and tool workflows while remaining largely compatible with AI SDK 5. The beta is intended for experimentation and feedback (file issues on GitHub); install with npm install ai@beta @ai-sdk/openai@beta @ai-sdk/react@beta and pin versions because APIs may still change. The release is a major version due to the spec upgrade but is not expected to introduce major breaking changes for most users; a stable release is planned by end of 2025. Key technical highlights: a new Agent interface plus a default ToolLoopAgent that manages LLM prompts, tool calling, and multi-step loops (e.g., model: openai('gpt-4o'), stopWhen: stepCountIs(20)). Tool approval lets agents request human confirmation conditionally (needsApproval or async checks), enabling secure human-in-the-loop flows and UI hooks to accept/deny invocations. Structured output is now stable for agents and for generateText/streamText via Output.object/array/choice/text and supports streaming partialOutputStream for incremental results. Reranking models (e.g., cohere.reranking('rerank-v3.5')) are natively supported to improve search relevance beyond embedding similarity, and native image editing/generation is coming soon. Overall, SDK6 formalizes agent patterns, safer tool execution, structured & streaming outputs, and reranking — practical building blocks for production agentic and retrieval applications.