# LangChain API Reference

> Comprehensive API documentation for LangChain Python and JavaScript libraries.
> LangChain is a framework for building applications with large language models (LLMs),
> including chains, agents, RAG pipelines, and tool-calling workflows.

Important notes:
- Python packages require Python 3.9+
- JavaScript packages require Node.js 18+
- Most LLM integrations require API keys from the respective providers
- All pages are available as markdown by appending `.md` to the URL

## Python Packages

- [langchain](https://reference.langchain.com/python/langchain.md): # 🦜️🔗 LangChain [![PyPI - Version](https://img.shields.io/pypi/v/langchain?label=%20)](https://pypi.org/project/langchain/#history) [![PyPI - Lic...
- [langchain_core](https://reference.langchain.com/python/langchain-core.md): # 🦜🍎️ LangChain Core [![PyPI - Version](https://img.shields.io/pypi/v/langchain-core?label=%20)](https://pypi.org/project/langchain-core/#history...
- [langchain_mcp_adapters](https://reference.langchain.com/python/langchain-mcp-adapters.md): # LangChain MCP Adapters This library provides a lightweight wrapper that makes [Anthropic Model Context Protocol (MCP)](https://modelcontextprotoc...
- [langchain_tests](https://reference.langchain.com/python/langchain-tests.md): # 🦜️🔗 langchain-tests [![PyPI - Version](https://img.shields.io/pypi/v/langchain-tests?label=%20)](https://pypi.org/project/langchain-tests/#hist...
- [langchain_text_splitters](https://reference.langchain.com/python/langchain-text-splitters.md): # 🦜✂️ LangChain Text Splitters [![PyPI - Version](https://img.shields.io/pypi/v/langchain-text-splitters?label=%20)](https://pypi.org/project/lang...
- [langchain_classic](https://reference.langchain.com/python/langchain-classic.md): # 🦜️🔗 LangChain Classic [![PyPI - Version](https://img.shields.io/pypi/v/langchain-classic?label=%20)](https://pypi.org/project/langchain-classic...
- [langgraph](https://reference.langchain.com/python/langgraph.md): <picture class="github-only"> <source media="(prefers-color-scheme: light)" srcset="https://langchain-ai.github.io/langgraph/static/wordmark_dark.s...
- [langgraph_cli](https://reference.langchain.com/python/langgraph-cli.md): # LangGraph CLI The official command-line interface for LangGraph, providing tools to create, develop, and deploy LangGraph applications
- [langgraph_sdk](https://reference.langchain.com/python/langgraph-sdk.md): # LangGraph Python SDK This repository contains the Python SDK for interacting with the LangSmith Deployment REST API
- [langgraph_supervisor](https://reference.langchain.com/python/langgraph-supervisor.md): # 🤖 LangGraph Multi-Agent Supervisor > **Note**: We now recommend using the **supervisor pattern directly via tools** rather than this library for...
- [langgraph_swarm](https://reference.langchain.com/python/langgraph-swarm.md): # 🤖 LangGraph Multi-Agent Swarm A Python library for creating swarm-style multi-agent systems using [LangGraph](https://github.com/langchain-ai/la...
- [deepagents](https://reference.langchain.com/python/deepagents.md): # 🧠🤖 Deep Agents [![PyPI - Version](https://img.shields.io/pypi/v/deepagents?label=%20)](https://pypi.org/project/deepagents/#history) [![PyPI - ...
- [deepagents_acp](https://reference.langchain.com/python/deepagents-acp.md): # Deep Agents ACP integration This directory contains an [Agent Client Protocol (ACP)](https://agentclientprotocol.com/overview/introduction) conne...
- [deepagents_cli](https://reference.langchain.com/python/deepagents-cli.md): # 🧠🤖 Deep Agents CLI [![PyPI - Version](https://img.shields.io/pypi/v/deepagents-cli?label=%20)](https://pypi.org/project/deepagents-cli/#history...
- [langchain_amazon_nova](https://reference.langchain.com/python/langchain-amazon-nova.md): # `langchain-amazon-nova` [![PyPI - Version](https://img.shields.io/pypi/v/langchain-amazon-nova?label=%20)](https://pypi.org/project/langchain-ama...
- [langchain_anthropic](https://reference.langchain.com/python/langchain-anthropic.md): # `langchain-anthropic` [![PyPI - Version](https://img.shields.io/pypi/v/langchain-anthropic?label=%20)](https://pypi.org/project/langchain-anthrop...
- [langchain_astradb](https://reference.langchain.com/python/langchain-astradb.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-astradb?label=%20)](https://pypi.org/project/langchain-astradb/#history) [![PyPI - Licen...
- [langchain_aws](https://reference.langchain.com/python/langchain-aws.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-aws?label=%20)](https://pypi.org/project/langchain-aws/#history) [![PyPI - License](http...
- [langchain_azure_dynamic_sessions](https://reference.langchain.com/python/langchain-azure-dynamic-sessions.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-azure-dynamic-sessions?label=%20)](https://pypi.org/project/langchain-azure-dynamic-sess...
- [langchain_cerebras](https://reference.langchain.com/python/langchain-cerebras.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-cerebras?label=%20)](https://pypi.org/project/langchain-cerebras/#history) [![PyPI - Lic...
- [langchain_chroma](https://reference.langchain.com/python/langchain-chroma.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-chroma?label=%20)](https://pypi.org/project/langchain-chroma/#history) [![PyPI - License...
- [langchain_cohere](https://reference.langchain.com/python/langchain-cohere.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-cohere?label=%20)](https://pypi.org/project/langchain-cohere/#history) [![PyPI - License...
- [langchain_community](https://reference.langchain.com/python/langchain-community.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-community?label=%20)](https://pypi.org/project/langchain-community/#history) [![PyPI - L...
- [langchain_db2](https://reference.langchain.com/python/langchain-db2.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-db2?label=%20)](https://pypi.org/project/langchain-db2/#history) [![PyPI - License](http...
- [langchain_deepseek](https://reference.langchain.com/python/langchain-deepseek.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-deepseek?label=%20)](https://pypi.org/project/langchain-deepseek/#history) [![PyPI - Lic...
- [langchain_elasticsearch](https://reference.langchain.com/python/langchain-elasticsearch.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-elasticsearch?label=%20)](https://pypi.org/project/langchain-elasticsearch/#history) [![...
- [langchain_exa](https://reference.langchain.com/python/langchain-exa.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-exa?label=%20)](https://pypi.org/project/langchain-exa/#history) [![PyPI - License](http...
- [langchain_fireworks](https://reference.langchain.com/python/langchain-fireworks.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-fireworks?label=%20)](https://pypi.org/project/langchain-fireworks/#history) [![PyPI - L...
- [langchain_google_community](https://reference.langchain.com/python/langchain-google-community.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-google-community?label=%20)](https://pypi.org/project/langchain-google-community/#histor...
- [langchain_google_genai](https://reference.langchain.com/python/langchain-google-genai.md): # `langchain-google-genai` [![PyPI - Version](https://img.shields.io/pypi/v/langchain-google-genai?label=%20)](https://pypi.org/project/langchain-g...
- [langchain_google_vertexai](https://reference.langchain.com/python/langchain-google-vertexai.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-google-vertexai?label=%20)](https://pypi.org/project/langchain-google-vertexai/#history)...
- [langchain_groq](https://reference.langchain.com/python/langchain-groq.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-groq?label=%20)](https://pypi.org/project/langchain-groq/#history) [![PyPI - License](ht...
- [langchain_huggingface](https://reference.langchain.com/python/langchain-huggingface.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-huggingface?label=%20)](https://pypi.org/project/langchain-huggingface/#history) [![PyPI...
- [langchain_ibm](https://reference.langchain.com/python/langchain-ibm.md): # `langchain-ibm` [![PyPI - Version](https://img.shields.io/pypi/v/langchain-ibm?label=%20)](https://pypi.org/project/langchain-ibm/#history) [![Py...
- [langchain_litellm](https://reference.langchain.com/python/langchain-litellm.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-litellm?label=%20)](https://pypi.org/project/langchain-litellm/#history) [![PyPI - Licen...
- [langchain_milvus](https://reference.langchain.com/python/langchain-milvus.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-milvus?label=%20)](https://pypi.org/project/langchain-milvus/#history) [![PyPI - License...
- [langchain_mistralai](https://reference.langchain.com/python/langchain-mistralai.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-mistralai?label=%20)](https://pypi.org/project/langchain-mistralai/#history) [![PyPI - L...
- [langchain_mongodb](https://reference.langchain.com/python/langchain-mongodb.md): Documentation for `langchain-mongodb` is hosted separately by the MongoDB team
- [langchain_neo4j](https://reference.langchain.com/python/langchain-neo4j.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-neo4j?label=%20)](https://pypi.org/project/langchain-neo4j/#history) [![PyPI - License](...
- [langchain_nomic](https://reference.langchain.com/python/langchain-nomic.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-nomic?label=%20)](https://pypi.org/project/langchain-nomic/#history) [![PyPI - License](...
- [langchain_nvidia_ai_endpoints](https://reference.langchain.com/python/langchain-nvidia-ai-endpoints.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-nvidia-ai-endpoints?label=%20)](https://pypi.org/project/langchain-nvidia-ai-endpoints/#...
- [langchain_ollama](https://reference.langchain.com/python/langchain-ollama.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-ollama?label=%20)](https://pypi.org/project/langchain-ollama/#history) [![PyPI - License...
- [langchain_openai](https://reference.langchain.com/python/langchain-openai.md): # `langchain-openai` [![PyPI - Version](https://img.shields.io/pypi/v/langchain-openai?label=%20)](https://pypi.org/project/langchain-openai/#histo...
- [langchain_openrouter](https://reference.langchain.com/python/langchain-openrouter.md): # `langchain-openrouter` [![PyPI - Version](https://img.shields.io/pypi/v/langchain-openrouter?label=%20)](https://pypi.org/project/langchain-openr...
- [langchain_parallel](https://reference.langchain.com/python/langchain-parallel.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-parallel?label=%20)](https://pypi.org/project/langchain-parallel/#history) [![PyPI - Lic...
- [langchain_perplexity](https://reference.langchain.com/python/langchain-perplexity.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-perplexity?label=%20)](https://pypi.org/project/langchain-perplexity/#history) [![PyPI -...
- [langchain_pinecone](https://reference.langchain.com/python/langchain-pinecone.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-pinecone?label=%20)](https://pypi.org/project/langchain-pinecone/#history) [![PyPI - Lic...
- [langchain_postgres](https://reference.langchain.com/python/langchain-postgres.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-postgres?label=%20)](https://pypi.org/project/langchain-postgres/#history) [![PyPI - Lic...
- [langchain_qdrant](https://reference.langchain.com/python/langchain-qdrant.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-qdrant?label=%20)](https://pypi.org/project/langchain-qdrant/#history) [![PyPI - License...
- [langchain_redis](https://reference.langchain.com/python/langchain-redis.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-redis?label=%20)](https://pypi.org/project/langchain-redis/#history) [![PyPI - License](...
- [langchain_sema4](https://reference.langchain.com/python/langchain-sema4.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-sema4?label=%20)](https://pypi.org/project/langchain-sema4/#history) [![PyPI - License](...
- [langchain_snowflake](https://reference.langchain.com/python/langchain-snowflake.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-snowflake?label=%20)](https://pypi.org/project/langchain-snowflake/#history) [![PyPI - L...
- [langchain_sqlserver](https://reference.langchain.com/python/langchain-sqlserver.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-sqlserver?label=%20)](https://pypi.org/project/langchain-sqlserver/#history) [![PyPI - L...
- [langchain_tavily](https://reference.langchain.com/python/langchain-tavily.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-tavily?label=%20)](https://pypi.org/project/langchain-tavily/#history) [![PyPI - License...
- [langchain_together](https://reference.langchain.com/python/langchain-together.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-together?label=%20)](https://pypi.org/project/langchain-together/#history) [![PyPI - Lic...
- [langchain_unstructured](https://reference.langchain.com/python/langchain-unstructured.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-unstructured?label=%20)](https://pypi.org/project/langchain-unstructured/#history) [![Py...
- [langchain_upstage](https://reference.langchain.com/python/langchain-upstage.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-upstage?label=%20)](https://pypi.org/project/langchain-upstage/#history) [![PyPI - Licen...
- [langchain_weaviate](https://reference.langchain.com/python/langchain-weaviate.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-weaviate?label=%20)](https://pypi.org/project/langchain-weaviate/#history) [![PyPI - Lic...
- [langchain_xai](https://reference.langchain.com/python/langchain-xai.md): [![PyPI - Version](https://img.shields.io/pypi/v/langchain-xai?label=%20)](https://pypi.org/project/langchain-xai/#history) [![PyPI - License](http...
- [langsmith](https://reference.langchain.com/python/langsmith.md): # LangSmith Client SDK [![Release Notes](https://img.shields.io/github/release/langchain-ai/langsmith-sdk?logo=python)](https://github.com/langchai...

## JavaScript Packages

- [langchain](https://reference.langchain.com/javascript/langchain.md): # 🦜️🔗 LangChain.js ![npm](https://img.shields.io/npm/dm/langchain) [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https:/...
- [@langchain/core](https://reference.langchain.com/javascript/langchain-core.md): # 🦜🍎️ @langchain/core ![npm](https://img.shields.io/npm/dm/@langchain/core) [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)...
- [@langchain/textsplitters](https://reference.langchain.com/javascript/langchain-textsplitters.md): # 🦜✂️ @langchain/textsplitters This package contains various implementations of LangChain.js text splitters, most commonly used as part of retriev...
- [@langchain/mcp-adapters](https://reference.langchain.com/javascript/langchain-mcp-adapters.md): # LangChain.js MCP Adapters [![npm version](https://img.shields.io/npm/v/@langchain/mcp-adapters.svg)](https://www.npmjs.com/package/@langchain/mcp...
- [@langchain/langgraph](https://reference.langchain.com/javascript/langchain-langgraph.md): # 🦜🕸️LangGraph.js [![Docs](https://img.shields.io/badge/docs-latest-blue)](https://langchain-ai.github.io/langgraphjs/) ![Version](https://img.sh...
- [@langchain/react](https://reference.langchain.com/javascript/langchain-react.md): # @langchain/react React SDK for building AI-powered applications with [Deep Agents](https://docs.langchain.com/oss/javascript/deepagents/overview)...
- [@langchain/vue](https://reference.langchain.com/javascript/langchain-vue.md): # @langchain/vue Vue SDK for building AI-powered applications with [Deep Agents](https://docs.langchain.com/oss/javascript/deepagents/overview), [L...
- [@langchain/svelte](https://reference.langchain.com/javascript/langchain-svelte.md): # @langchain/svelte Svelte SDK for building AI-powered applications with [Deep Agents](https://docs.langchain.com/oss/javascript/deepagents/overvie...
- [@langchain/angular](https://reference.langchain.com/javascript/langchain-angular.md): # @langchain/angular Angular SDK for building AI-powered applications with [Deep Agents](https://docs.langchain.com/oss/javascript/deepagents/overv...
- [@langchain/langgraph-sdk](https://reference.langchain.com/javascript/langchain-langgraph-sdk.md): # LangGraph JS/TS SDK This repository contains the JS/TS SDK for interacting with the LangGraph REST API
- [@langchain/langgraph-checkpoint](https://reference.langchain.com/javascript/langchain-langgraph-checkpoint.md): # @langchain/langgraph-checkpoint This library defines the base interface for [LangGraph.js](https://github.com/langchain-ai/langgraphjs) checkpoin...
- [@langchain/langgraph-checkpoint-mongodb](https://reference.langchain.com/javascript/langchain-langgraph-checkpoint-mongodb.md): # @langchain/langgraph-checkpoint-mongodb Implementation of a [LangGraph.js](https://github.com/langchain-ai/langgraphjs) CheckpointSaver that uses...
- [@langchain/langgraph-checkpoint-postgres](https://reference.langchain.com/javascript/langchain-langgraph-checkpoint-postgres.md): # @langchain/langgraph-checkpoint-postgres Implementation of a [LangGraph.js](https://github.com/langchain-ai/langgraphjs) CheckpointSaver that use...
- [@langchain/langgraph-checkpoint-redis](https://reference.langchain.com/javascript/langchain-langgraph-checkpoint-redis.md): # @langchain/langgraph-checkpoint-redis Redis checkpoint and store implementation for LangGraph
- [@langchain/langgraph-checkpoint-sqlite](https://reference.langchain.com/javascript/langchain-langgraph-checkpoint-sqlite.md): # @langchain/langgraph-checkpoint-sqlite Implementation of a [LangGraph.js](https://github.com/langchain-ai/langgraphjs) CheckpointSaver that uses ...
- [@langchain/langgraph-checkpoint-validation](https://reference.langchain.com/javascript/langchain-langgraph-checkpoint-validation.md): # @langchain/langgraph-checkpoint-validation The checkpointer validation tool is used to validate that custom checkpointer implementations conform ...
- [@langchain/langgraph-api](https://reference.langchain.com/javascript/langchain-langgraph-api.md): # LangGraph.js API In-memory implementation of the LangGraph.js API
- [@langchain/langgraph-cli](https://reference.langchain.com/javascript/langchain-langgraph-cli.md): # LangGraph.js CLI The official command-line interface for LangGraph.js, providing tools to create, develop, and deploy LangGraph.js applications
- [@langchain/langgraph-cua](https://reference.langchain.com/javascript/langchain-langgraph-cua.md): # 🤖 LangGraph.js Computer Use Agent (CUA) > [!TIP] > Looking for the Python version? [Check out the repo here](https://github.com/langchain-ai/lan...
- [@langchain/langgraph-supervisor](https://reference.langchain.com/javascript/langchain-langgraph-supervisor.md): # 🤖 LangGraph Multi-Agent Supervisor A JavaScript library for creating hierarchical multi-agent systems using [LangGraph](https://github.com/langc...
- [@langchain/langgraph-swarm](https://reference.langchain.com/javascript/langchain-langgraph-swarm.md): # 🤖 LangGraph Multi-Agent Swarm A JavaScript library for creating swarm-style multi-agent systems using [LangGraph](https://github.com/langchain-a...
- [deepagents](https://reference.langchain.com/javascript/deepagents.md): <div align="center"> <a href="https://docs.langchain.com/oss/python/deepagents/overview#deep-agents-overview"> <picture> <source media="(prefers-co...
- [deepagents-acp](https://reference.langchain.com/javascript/deepagents-acp.md): # deepagents-acp ACP (Agent Client Protocol) server for DeepAgents - enables integration with IDEs like Zed, JetBrains, and other ACP-compatible cl...
- [@langchain/modal](https://reference.langchain.com/javascript/langchain-modal.md): # @langchain/modal Modal Sandbox backend for [deepagents](https://www.npmjs.com/package/deepagents)
- [@langchain/daytona](https://reference.langchain.com/javascript/langchain-daytona.md): # @langchain/daytona Daytona Sandbox backend for [deepagents](https://www.npmjs.com/package/deepagents)
- [@langchain/deno](https://reference.langchain.com/javascript/langchain-deno.md): # @langchain/deno Deno Sandbox backend for [deepagents](https://www.npmjs.com/package/deepagents)
- [@langchain/node-vfs](https://reference.langchain.com/javascript/langchain-node-vfs.md): # @langchain/node-vfs Node.js Virtual File System backend for [DeepAgents](https://github.com/langchain-ai/deepagentsjs)
- [@langchain/sandbox-standard-tests](https://reference.langchain.com/javascript/langchain-sandbox-standard-tests.md): # @langchain/sandbox-standard-tests Shared integration test suites for [deepagents](https://github.com/langchain-ai/deepagentsjs) sandbox providers
- [@langchain/community](https://reference.langchain.com/javascript/langchain-community.md): # 🦜️🧑‍🤝‍🧑 LangChain Community [![CI](https://github.com/langchain-ai/langchainjs/actions/workflows/ci.yml/badge.svg)](https://github.com/langch...
- [@langchain/anthropic](https://reference.langchain.com/javascript/langchain-anthropic.md): # @langchain/anthropic This package contains the LangChain.js integrations for Anthropic through their SDK
- [@langchain/aws](https://reference.langchain.com/javascript/langchain-aws.md): # @langchain/aws This package contains the LangChain.js integrations for AWS through their SDK
- [@langchain/azure-cosmosdb](https://reference.langchain.com/javascript/langchain-azure-cosmosdb.md): # @langchain/azure-cosmosdb This package contains the [Azure CosmosDB](https://learn.microsoft.com/azure/cosmos-db/) vector store integrations
- [@langchain/azure-dynamic-sessions](https://reference.langchain.com/javascript/langchain-azure-dynamic-sessions.md): # @langchain/azure-dynamic-sessions This package contains the [Azure Container Apps dynamic sessions](https://learn.microsoft.com/azure/container-a...
- [@langchain/baidu-qianfan](https://reference.langchain.com/javascript/langchain-baidu-qianfan.md): # @langchain/baidu-qianfan This package contains the LangChain.js integrations for Baidu Qianfan via the qianfan/sdk package
- [@langchain/cerebras](https://reference.langchain.com/javascript/langchain-cerebras.md): # @langchain/cerebras This package contains the LangChain.js integrations for Cerebras via the `@cerebras/cerebras_cloud_sdk` package
- [@langchain/cloudflare](https://reference.langchain.com/javascript/langchain-cloudflare.md): # @langchain/cloudflare This package contains the LangChain.js integrations for Cloudflare through their SDK
- [@langchain/cohere](https://reference.langchain.com/javascript/langchain-cohere.md): # @langchain/cohere This package contains the LangChain.js integrations for Cohere through their SDK
- [@langchain/deepseek](https://reference.langchain.com/javascript/langchain-deepseek.md): # @langchain/deepseek This package contains the LangChain.js integrations for DeepSeek
- [@langchain/exa](https://reference.langchain.com/javascript/langchain-exa.md): # @langchain/exa This package contains the LangChain.js integrations for exa through their SDK
- [@langchain/google](https://reference.langchain.com/javascript/langchain-google.md): # @langchain/google This package supports access to a variety of Google's models, including the Gemini family of models and their Nano Banana image...
- [@langchain/google-cloud-sql-pg](https://reference.langchain.com/javascript/langchain-google-cloud-sql-pg.md): # @langchain/google-cloud-sql-pg The LangChain package for CloudSQL for Postgres provides a way to connect to Cloud SQL instances from the LangChai...
- [@langchain/google-common](https://reference.langchain.com/javascript/langchain-google-common.md): # LangChain google-common This package contains common resources to access Google AI/ML models and other Google services in an auth-independent way
- [@langchain/google-gauth](https://reference.langchain.com/javascript/langchain-google-gauth.md): # LangChain google-gauth This package contains resources to access Google AI/ML models and other Google services
- [@langchain/google-genai](https://reference.langchain.com/javascript/langchain-google-genai.md): # @langchain/google-genai This package contains the LangChain.js integrations for Gemini through their generative-ai SDK
- [@langchain/google-vertexai](https://reference.langchain.com/javascript/langchain-google-vertexai.md): # LangChain google-vertexai This package contains resources to access Google AI/ML models and other Google services via Vertex AI
- [@langchain/google-vertexai-web](https://reference.langchain.com/javascript/langchain-google-vertexai-web.md): # LangChain google-vertexai-web This package contains resources to access Google AI/ML models and other Google services via Vertex AI
- [@langchain/google-webauth](https://reference.langchain.com/javascript/langchain-google-webauth.md): # LangChain google-webauth This package contains resources to access Google AI/ML models and other Google services
- [@langchain/groq](https://reference.langchain.com/javascript/langchain-groq.md): # @langchain/groq This package contains the LangChain.js integrations for Groq via the groq/sdk package
- [@langchain/mistralai](https://reference.langchain.com/javascript/langchain-mistralai.md): # @langchain/mistralai This package contains the LangChain.js integrations for Mistral through their SDK
- [@langchain/mixedbread-ai](https://reference.langchain.com/javascript/langchain-mixedbread-ai.md): # @langchain/mixedbread-ai This package contains the LangChain.js integrations for the [Mixedbread AI API](https://mixedbread.ai/)
- [@langchain/mongodb](https://reference.langchain.com/javascript/langchain-mongodb.md): # @langchain/mongodb This package contains the LangChain.js integrations for MongoDB through their SDK
- [@langchain/nomic](https://reference.langchain.com/javascript/langchain-nomic.md): # @langchain/nomic This package contains the LangChain.js integrations for Nomic via the @nomic-ai/atlas package
- [@langchain/ollama](https://reference.langchain.com/javascript/langchain-ollama.md): # @langchain/ollama This package contains the LangChain.js integrations for Ollama via the `ollama` TypeScript SDK
- [@langchain/openai](https://reference.langchain.com/javascript/langchain-openai.md): # @langchain/openai This package contains the LangChain.js integrations for OpenAI through their SDK
- [@langchain/openrouter](https://reference.langchain.com/javascript/langchain-openrouter.md): # @langchain/openrouter This package contains the LangChain.js integrations for [OpenRouter](https://openrouter.ai/)
- [@langchain/pinecone](https://reference.langchain.com/javascript/langchain-pinecone.md): # @langchain/pinecone This package contains the LangChain.js integrations for Pinecone through their SDK
- [@langchain/qdrant](https://reference.langchain.com/javascript/langchain-qdrant.md): # @langchain/qdrant This package contains the LangChain.js integration for the [Qdrant](https://qdrant.tech/) vector database
- [@langchain/redis](https://reference.langchain.com/javascript/langchain-redis.md): # @langchain/redis This package contains the LangChain.js integrations for Redis through their SDK
- [@langchain/tavily](https://reference.langchain.com/javascript/langchain-tavily.md): # `@langchain/tavily` [![NPM - Version](https://img.shields.io/npm/v/@langchain/tavily?style=flat-square&label=%20)](https://www.npmjs.com/package/...
- [@langchain/turbopuffer](https://reference.langchain.com/javascript/langchain-turbopuffer.md): # @langchain/turbopuffer This package contains the LangChain.js integration for the [turbopuffer](https://turbopuffer.com/) vector database
- [@langchain/weaviate](https://reference.langchain.com/javascript/langchain-weaviate.md): # @langchain/weaviate This package contains the LangChain.js integrations for Weaviate with the `weaviate-client` SDK
- [@langchain/xai](https://reference.langchain.com/javascript/langchain-xai.md): # @langchain/xai This package contains the LangChain.js integrations for xAI
- [@langchain/yandex](https://reference.langchain.com/javascript/langchain-yandex.md): # @langchain/yandex This package contains the LangChain.js integrations for YandexGPT through their [Foundation Models REST API](https://cloud.yand...
- [langsmith](https://reference.langchain.com/javascript/langsmith.md): # LangSmith Client SDK ![NPM Version](https://img.shields.io/npm/v/langsmith?logo=npm) [![JS Downloads](https://img.shields.io/npm/dm/langsmith)](h...

## Accessing Documentation

All pages support markdown format for AI consumption:

**URL patterns:**

- Package overview: `https://reference.langchain.com/python/langchain-core.md`
- Symbol page: `https://reference.langchain.com/python/langchain-core/RunnableSequence.md`
- Nested symbol: `https://reference.langchain.com/python/langchain-core/RunnableSequence/invoke.md`

Markdown is also served automatically when:
- `Accept: text/markdown` header is present
- User-Agent matches LLM patterns (GPTBot, Claude-Web, cursor, copilot)
- Request is from CLI tools (curl, wget, httpie)

## MCP Server

This documentation is available as an MCP (Model Context Protocol) server
for integration with AI coding assistants:

`https://reference.langchain.com/mcp`

Compatible with Cursor, VS Code, Claude Desktop, and other MCP clients.

## Optional

- [Skill file](https://reference.langchain.com/skill.md): Best practices and usage guide for AI agents
- [Full symbol index](https://reference.langchain.com/llms-full.txt): Complete listing of all symbols
- [LangChain Documentation](https://docs.langchain.com/): Tutorials and guides
- [LangChain GitHub](https://github.com/langchain-ai/langchain): Python source code
- [LangChain.js GitHub](https://github.com/langchain-ai/langchainjs): JavaScript source code
- [LangSmith](https://smith.langchain.com/): Observability and tracing platform