OpenUI SDK

API reference for the documented surfaces of @openuidev/react-lang, @openuidev/react-headless, @openuidev/react-ui, and @openuidev/react-email.

The OpenUI SDK is split into packages that build on each other:

@openuidev/react-lang — Core runtime. Define component libraries with Zod schemas, generate system prompts, parse OpenUI Lang, and render streamed output to React. This is the foundation — you need it for any OpenUI integration.
@openuidev/react-headless — Headless chat state management. Provides ChatProvider, thread/message hooks, streaming protocol adapters (OpenAI, AG-UI), and message format converters. Use this when you want full control over your chat UI.
@openuidev/react-ui — Prebuilt chat layouts (Copilot, FullScreen, BottomTray) and two ready-to-use component libraries (general-purpose and chat-optimized). Depends on both packages above. Use this for the fastest path to a working chat interface.
@openuidev/react-email — API reference for the pre-built email templates library and prompt options.
@openuidev/cli — Command-line tool for scaffolding new OpenUI chat apps and generating system prompts or JSON schemas from library definitions.

Packages

defineComponent, createLibrary, Renderer, parser APIs, action types, context hooks, and form validation.

ChatProvider, useThread/useThreadList, stream protocol adapters (OpenAI, AG-UI), and message format converters.

Copilot, FullScreen, BottomTray chat layouts, and two built-in component libraries (general-purpose and chat-optimized).

API reference for the pre-built email templates library and prompt options.

openui create (scaffold a Next.js app) and openui generate (system prompt / JSON schema from a library definition).