assistant-ui is an open-source library built with TypeScript and React, designed for rapidly creating AI chat interfaces. It streamlines common tasks like streaming, auto-scrolling, and real-time updates, removing much of the manual effort typically involved in chat application development. The library is modular, allowing developers to customize every aspect of their chat experience, inspired by existing UI frameworks like shadcn/ui and cmdk. It supports a wide range of AI models, including OpenAI, Anthropic, and Google Gemini, among others. This flexibility extends to backend integration; whether you’re using AI SDK, LangGraph, or a custom solution, assistant-ui can fit into your setup. The focus on developer experience is evident in its sensible defaults, built-in accessibility features, and robust TypeScript support. You can quickly scaffold a new project or integrate it into an existing one using simple terminal commands. The library emphasizes composability, enabling developers to create tailored user experiences without being tied to a single widget. It includes features like message lists, input fields, and toolbars, all optimized for production use with built-in functionalities like markdown support and voice input. For enterprise users, assistant-ui offers optional chat history and analytics through its Assistant Cloud service, which can easily be deployed alongside your chat application.