assistant-ui/assistant-ui

What it solves

It eliminates the need to build complex AI chat interfaces from scratch in React applications. It provides the production-ready UI components and the plumbing required to connect a frontend to various AI backends, ensuring a polished user experience without manual implementation of streaming, auto-scrolling, or accessibility.

How it works

The library provides a set of composable React primitives (such as Thread, Message, and Composer) that developers can use to build their chat UI. It uses a runtime provider system to connect these UI components to different AI backends via adapters. It supports out-of-the-box integrations with the Vercel AI SDK, LangGraph, and LangChain, while also allowing for custom data-stream backends.

Who it’s for

Frontend and full-stack developers using TypeScript and React (including Next.js) who want to integrate a professional AI chat interface into their application quickly.

Highlights

• Composable UI: Offers flexible primitives that can be styled individually or started with a shadcn/ui theme.
• Production Features: Includes built-in support for streaming, markdown, code highlighting, voice dictation, and keyboard shortcuts.
• Generative UI: Capable of rendering tool calls and JSON as interactive React components with human approval workflows.
• Broad Backend Support: Integrates with major LLM providers (OpenAI, Anthropic, Gemini, etc.) through various SDKs and custom HTTP backends.