Persona.js
Build agentic web chat UIs in VanillaJS for any site and backend
Persona is an open source agent UI library that helps you build chat-based, agentic experiences on the web in pure JavaScript. It runs on any stack, streams from any SSE backend, and discovers page tools via WebMCP so agents can operate carts, forms, and search with user approval built in. Style it to match your brand, choose floating, docked, or fullscreen layouts, and embed it without breaking host styles thanks to Shadow DOM isolation.
If you are tired of rebuilding your entire app or website to get a great looking native AI experience to work with it, you'll love Persona!