OpenUI

Choose OpenUI over Vercel's json-render or AI SDK generative UI when token cost and streaming latency actually matter — the benchmark in the repo shows about 50% fewer tokens across seven scenarios, and the renderer paints partial output as it arrives. Start from `@openuidev/react-lang` + `@openuidev/react-ui` if you want the built-in kit, or `lang-core` alone if you only need prompt generation on the server. Two traps: the models must be constrained to the components you register or output silently fails to render, and this is thesysdev/openui — completely unrelated to the older wandb/openui HTML generator with a similar name.

Why it is here. Generative UI is drifting toward a shared wire format, and this is the most complete open bid for it — a language, a renderer, a component library and framework bindings under one MIT licence.