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

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Reference sites

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Deep Agents

Build agents that can plan, use subagents, and leverage file systems for complex tasks.
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LangChain

Complete API reference for LangChain Python, including chat models, tools, agents, and more.
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LangGraph

Complete API reference for LangGraph Python, including graph APIs, state management, checkpointing, and more.

LangChain Integrations

LangChain packages to connect with popular LLM providers, vector stores, tools, and other services.

MCP Adapter

Use Model Context Protocol (MCP) tools within LangChain and LangGraph applications.
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