What is Agent Chat UI used for?

Agent Chat UI is a Next.js chat interface from LangChain for talking to any LangGraph agent server, written for Python or TypeScript deployments. It is a good fit for testing LangGraph agents during development and demoing an agent to stakeholders.

Is Agent Chat UI open source?

Yes. Agent Chat UI is open source under the MIT licence. Its source code is on GitHub at langchain-ai/agent-chat-ui and is written mainly in TypeScript.

Is Agent Chat UI free?

Yes. Agent Chat UI is open source, so the software itself is free to use. A managed cloud version is also available.

What are some alternatives to Agent Chat UI?

Similar open-source tools in the AI Tools category include LobeHub, Agno Agent UI and OpenHands. SaaS products in the same category include AtomicBot.ai, ChatATP and JetBrains AI Assistant.

Is Agent Chat UI actively maintained?

Yes. The most recent commit to Agent Chat UI was on 28 September 2026. The project has 3.2k stars on GitHub.

Agent Chat UI: open-source AI tools

About Agent Chat UI

Agent Chat UI is a web application from the LangChain team that provides a chat interface for LangGraph agents. It is a Next.js app that can connect to any LangGraph server whose state has a messages key, so developers can test and demonstrate an agent they have built without writing their own front end. It is released under the MIT license.

On first launch you enter the deployment URL of the LangGraph server and the ID of the graph or assistant to use, plus a LangSmith API key if the server is a deployed one that needs authentication. After you continue, the app opens a chat view for the agent. These values can also be set as environment variables to skip the initial form, and there is a toggle for Agent Builder deployments.

You can clone the repository and run it locally, start it with an npx command, or use the hosted copy at agentchat.vercel.app. It suits developers working on LangGraph agents in Python or TypeScript who need a ready-made interface for testing and sharing.

Key features

Chat interface for any LangGraph server
Works with Python and TypeScript agents
Configurable deployment URL and graph ID
LangSmith API key authentication support
Environment variables to skip the setup form
Hosted version available online

Good fit for

→Testing LangGraph agents during development
→Demoing an agent to stakeholders

Built with: TypeScript
Tags: langgraph; langchain; ai-agents; chat-ui; nextjs; llm; agents; typescript

Agent Chat UI: questions and answers

What is Agent Chat UI used for?: Agent Chat UI is a Next.js chat interface from LangChain for talking to any LangGraph agent server, written for Python or TypeScript deployments. It is a good fit for testing LangGraph agents during development and demoing an agent to stakeholders.
Is Agent Chat UI open source?: Yes. Agent Chat UI is open source under the MIT licence. Its source code is on GitHub at langchain-ai/agent-chat-ui and is written mainly in TypeScript.
Is Agent Chat UI free?: Yes. Agent Chat UI is open source, so the software itself is free to use. A managed cloud version is also available.
What are some alternatives to Agent Chat UI?: Similar open-source tools in the AI Tools category include LobeHub, Agno Agent UI and OpenHands. SaaS products in the same category include AtomicBot.ai, ChatATP and JetBrains AI Assistant.
Is Agent Chat UI actively maintained?: Yes. The most recent commit to Agent Chat UI was on 28 September 2026. The project has 3.2k stars on GitHub.