Agent Chat UI

Agent Chat UI gives developers a web interface for talking to their LangGraph agents and returning to existing conversations. It connects to an agent server you choose, so you can use it with a local development server or a remote deployment.

• Agent conversations: Chat with Python and TypeScript LangGraph agents, retrieve conversation threads, and send actions to a selected graph or assistant.
• Streaming controls: Display replies as they're generated, suppress streaming for selected model calls, or hide internal messages from the conversation entirely.
• Artifact panel: Show additional agent content in a side panel beside the chat.
• Agent Builder support: Connect to LangSmith Agent Builder deployments as well as other compatible LangGraph servers.

The MIT-licensed Next.js app can run locally or through the hosted site at agentchat.vercel.app. The frontend and agent server run separately; using the hosted interface doesn't move your agent onto that site. Compatible agents must include a messages key in their state.

A local LangGraph server doesn't require a LangSmith API key. If you enter a key in the connection form, the app stores it in your browser's local storage and uses it to authenticate requests to your LangGraph server. The default connection goes directly from the browser to that server. Production deployments support a server-side API proxy or custom authentication; the proxy alone doesn't authenticate visitors.