assistant-ui

React library for building composable AI chat interfaces with streaming support and flexible runtime adapters. Always consult assistant-ui.com/llms.txt for latest API. React library for building AI chat interfaces with composable primitives. - Layered architecture with UI primitives (ThreadPrimitive, MessagePrimitive, ComposerPrimitive), context hooks, runtime layer, and pluggable backend adapters - Supports multiple runtime options: Vercel AI SDK, LangGraph, external state stores (Redux/Zustand), AG-UI protocol, A2A protocol, or custom APIs - Core packages include @assistant-ui/react for primitives, @assistant-ui/react-ai-sdk for AI SDK v6 integration, and @assistant-ui/react-markdown for rendering - Built-in state access via useAui() and useAuiState() hooks for thread management, message appending, and run control - Designed for production use with optional cloud persistence, multi-thread management, and custom message types (tools, images, files) - ./references/architecture.md -- Core architecture and layered system - ./references/packages.md -- Package overview and selection guide - /setup - Installation and configuration - /primitives - UI component customization - /runtime - State management deep dive - /tools - Tool registration and UI - /streaming - Streaming protocols - /cloud - Persistence and auth - /thread-list - Multi-thread management - /update - Version updates...