You are viewing the v1 docs for LangChain, which is currently under active development. Learn more.
LangChain provides a powerful prebuilt user interface that work seamlessly with agents created using create_agent(). This UI is designed to provide rich, interactive experiences for your agents with minimal setup, whether you’re running locally or in a deployed context (such as LangGraph Platform).

Agent Chat UI

Agent Chat UI is a Next.js application that provides a conversational interface for interacting with any LangChain agent. It supports real-time chat, tool visualization, and advanced features like time-travel debugging and state forking. Agent Chat UI is open source and can be adapted to your application needs. Find the repository here.

Features

Quick start

The fastest way to get started is using the hosted version:
  1. Visit Agent Chat UI
  2. Connect your agent by entering your deployment URL or local server address
  3. Start chatting - the UI will automatically detect and render tool calls and interrupts

Local development

For customization or local development, you can run Agent Chat UI locally:
# Create a new Agent Chat UI project
npx create-agent-chat-app my-chat-ui
cd my-chat-ui

# Install dependencies and start
pnpm install
pnpm dev

Connect to your agent

Agent Chat UI can connect to both local and deployed agents. After starting Agent Chat UI, you’ll need to configure it to connect to your agent:
  1. Graph ID: Enter your graph name (find this under graphs in your langgraph.json file)
  2. Deployment URL: Your LangGraph server’s endpoint (e.g., http://localhost:2024 for local development, or your deployed agent’s URL)
  3. LangSmith API key (optional): Add your LangSmith API key (not required if you’re using a local LangGraph server)
Once configured, Agent Chat UI will automatically fetch and display any interrupted threads from your agent.
Agent Chat UI has out-of-the-box support for rendering tool calls and tool result messages. To customize what messages are shown, see Hiding Messages in the Chat.