Agent runtime

Vercel AI SDK

The TypeScript toolkit for AI product interfaces — streaming chat state, tool-call rendering, and generative UI for React and other frameworks — the front-of-house counterpart to an agent backend.

Operating principle

Production AI is a system: context, tools, permissions, traces, evals, and feedback loops around the model.

What it is

The Vercel AI SDK (the open-source 'ai' package plus framework bindings like @ai-sdk/react) gives product teams the client machinery of an AI interface: the useChat hook for streaming conversation state, typed message parts (text, reasoning, tool calls, sources, files), and a data-stream protocol any backend can speak — the server does not have to be Vercel's or even TypeScript.

Why it matters

Streaming UX is table stakes, and it is subtle to build raw: token streaming, tool status, citations, interruptions, and error recovery all have edge cases. The SDK standardizes the wire format between the agent backend and the interface, so the UI renders typed parts instead of parsing text.

How we use it

Our product frontends run useChat with a custom transport against the agent backend's stream. Reasoning traces, tool confirmations, citations, and chart payloads arrive as typed message parts and render as native interface components rather than markdown blobs.

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