# LangChain Docs MCP

This repo uses LangChain, LangGraph, DeepAgents, and related LangChain ecosystem packages. Use current docs when changing those integration points.

## MCP server

Project-local MCP configuration lives in `.mcp.json`:

```json
{
  "mcpServers": {
    "langchain-docs": {
      "type": "http",
      "url": "https://docs.langchain.com/mcp"
    }
  }
}
```

## Documentation index

Before exploring individual pages, fetch the complete documentation index:

```text
https://docs.langchain.com/llms.txt
```

Use that index to discover the relevant LangChain, LangGraph, LangSmith, or DeepAgents page before reading deeper.

## Codex CLI fallback

If the project-local `.mcp.json` is not picked up by your client, register the server manually:

```bash
codex mcp add langchain-docs --url https://docs.langchain.com/mcp
```

If that command fails with `Failed to create OAuth session`, continue using the checked-in `.mcp.json` and retry the CLI registration after refreshing Codex authentication.