> ## Documentation Index
> Fetch the complete documentation index at: https://langchain-5e9cc07a-preview-devupd-1765394015-eccef47.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Reference

Comprehensive API reference documentation for the LangChain and LangGraph Python and TypeScript libraries.

## Reference sites

<CardGroup cols={2}>
  <Card title="LangChain" icon="link" href="https://reference.langchain.com/javascript/modules/langchain.html">
    Complete API reference for LangChain JavaScript/TypeScript, including chat models, tools, agents, and more.
  </Card>

  <Card title="LangGraph" icon="diagram-project" href="https://reference.langchain.com/javascript/modules/_langchain_langgraph.html">
    Complete API reference for LangGraph JavaScript/TypeScript, including graph APIs, state management, checkpointing, and more.
  </Card>
</CardGroup>

***

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