This directory contains the source code and build process for the Python reference documentation site, hosted at reference.langchain.com/python. This site serves references for LangChain, LangGraph, LangSmith, and LangChain integration packages (such as langchain-anthropic, langchain-openai, etc.).

The site is built using MkDocs with the Material for MkDocs theme and the mkdocstrings plugin for generating API reference documentation from docstrings. See all config options in the mkdocs.yml file.

The docs/ directory contains the markdown files for the site, with the main entry point being index.md. At build time, the stubs provided in each file are substituted with the generated API reference documentation by mkdocstrings. This allows us to architect content ordering, layout, etc. in markdown, while still generating the API reference documentation automatically from the source code. Consequently, to make content changes to the API references themselves, you need to make changes in the source code (e.g., docstrings, class/method names, etc.) and then rebuild the site.

Contributing

As these docs are built from the source code, the best way to contribute is to make changes in the source code itself. This can include:

Improving docstrings
Adding missing docstrings
Fixing typos
etc.

TODO

This site is currently being migrated from a previous Sphinx-based implementation, so there are still some rough edges to be smoothed out. Here are some known issues and potential improvements:

For methods that are from base classes, indicate it is inherited from such and link to the base class
Backlinks
More xref
Modernize annotations
Inheritance diagrams
Consider using inherited docstrings
Pydantic object refs preloading so that we link to them? Should find their tree and load it in (like we did for old LC)
Post-processing step to link out to imports from code blocks
- Maybe there's a plugin?
Fix navigation.path feature/plugin in mkdocs.yml not working
Resolve Griffe errors
Set up CI to fail on unexpected Griffe warnings
"Module last updated" auto-generation for module pages using source file commit timestamps or the MkDocs plugin git-revision-date-localized
Fix search magnifying glass icon color in dark mode
Copy page support (need to add a post-processing step to generate markdown files to serve alongside the API reference docs)
Language switcher (JS/TS)
Social cards
Google Analytics
Versioning?
Show keyboard shortcut in search window - also add cmd + k to match Mintlify

Paths

For packages that live in the langchain-ai/langchain monorepo, the path to the package should exist at https://reference.langchain.com/python/{PACKAGE}/ where PACKAGE is the package name as defined in the pyproject.toml file, with hyphens replaced by underscores. For example, the langchain-openai package should be documented at https://reference.langchain.com/python/langchain_openai/.

Local Development

Setup

This project supports two installation modes:

Development mode (pyproject.dev.toml) - Uses local editable installs from cloned repositories
Production mode (pyproject.toml) - Uses git sources directly

Development Workflow

For local development with live source code:

# 1. Ensure repos are cloned in the expected structure (see below)

# 2. Switch to development mode and install
make dev-install

# 3. Serve the docs locally
make serve-docs

# Check current configuration anytime
make config-status

When you edit source code in the local repositories, changes will be reflected immediately since packages are installed as editable.

How it works: The make dev-install command:

Switches pyproject.toml to use local editable installs (via switch-config.sh)
Backs up the production config to pyproject.prod.toml
Installs all packages from local repos with uv sync

Production/CI Workflow

For production builds or CI:

# Switch to production mode and install
make prod-install

# Build the documentation
make build

How it works: The make prod-install command:

Restores pyproject.toml to use git sources
Installs all packages from git with uv sync --link-mode=copy

Manual Configuration Switching

You can also use the script directly:

# Switch to development mode
./switch-config.sh dev

# Switch to production mode
./switch-config.sh prod

# Check current mode
./switch-config.sh status

Required Repository Structure

The pyproject.dev.toml file expects repositories to be cloned in this structure:

/some-parent-folder/
  ├── docs/                  # This repository
  │   └── reference/python/
  ├── langchain/             # Main LangChain monorepo
  ├── langgraph/             # Main LangGraph monorepo
  ├── langchain-community/
  ├── langchain-mcp-adapters/
  ├── langchain-datastax/
  ├── langchain-ai21/
  ├── langchain-aws/
  ├── langchain-azure/
  ├── langchain-cerebras/
  ├── langchain-cohere/
  ├── langchain-ibm/
  ├── langchain-elastic/
  ├── langchain-google/
  ├── langchain-milvus/
  ├── langchain-mongodb/
  ├── langchain-neo4j/
  ├── langchain-nvidia/
  ├── langchain-pinecone/
  ├── langchain-postgres/
  ├── langchain-redis/
  ├── langchain-sema4/
  ├── langchain-snowflake/
  ├── langchain-tavily/
  ├── langchain-together/
  ├── langchain-unstructured/
  ├── langchain-upstage/
  ├── langchain-weaviate/
  ├── langgraph-supervisor-py/
  └── langgraph-swarm-py/

If you only need to work on specific packages, you can comment out the others in pyproject.dev.toml.