Contributing to documentation

We welcome contributions to LangChain documentation, including new features, integrations, and improvements to existing docs.

Quick start - local development

To run a local preview of the documentation:

git clone https://github.com/langchain-ai/docs.git

cd docs

Install the pinned toolchain with mise, which reads the versions of Python, Node.js, uv, Vale, and the Mintlify CLI from .mise.toml and installs the repository's git hooks:

mise trust && mise install

make install

make dev

This starts a development server with hot reload at http://localhost:3000. Edit files in src/ and see changes immediately.

Edit documentation

1. Edit files in src/ following our writing standards.
2. Run quality checks before submitting.
3. Create a pull request for review.

Run quality checks

Before submitting changes, ensure your code passes formatting and linting checks:

# Check broken links and anchors
make broken-links-with-anchors

# Format code automatically
make format

# Check for linting issues
make lint

# Fix markdown issues
make lint_md_fix

# Run tests to ensure your changes don't break existing functionality
make test

For more details, see the available commands section in the README.

Documentation types

All documentation falls under one of four categories:

How-to guides

How-to guides are task-oriented instructions for users who know what they want to accomplish. Examples of how-to guides are on the LangChain and LangGraph tabs.

Conceptual guides

Conceptual guide cover core concepts abstractly, providing deep understanding.

Reference

Reference documentation contains detailed, low-level information describing exactly what functionality exists and how to use it.

A good reference should:

• Describe what exists (all parameters, options, return values)
• Be comprehensive and structured for easy lookup
• Serve as the authoritative source for technical details

Tutorials

Tutorials are longer form step-by-step guides that builds upon itself and takes users through a specific practical activity to build understanding. Tutorials are typically found on the Learn tab.

Writing standards

Mintlify components

Use Mintlify components to enhance readability:

Mermaid diagrams

When adding mermaid diagrams, use the LangChain brand color palette for node styling. Copy classDef lines from any existing diagram, or use the reference table in AGENTS.md.

Do not use Tailwind defaults, Material Design colors, or other off-brand palettes.

Page structure

Every documentation page must begin with YAML frontmatter:

---
title: "Clear, specific title"
sidebarTitle: "Short title for the sidebar (optional)"
---

Co-locate Python and JavaScript/TypeScript content

All documentation must be written in both Python and JavaScript/TypeScript when possible. To do so, we use a custom in-line syntax to differentiate between sections that should appear in one or both languages:

:::python
Python-specific content. In real docs, the preceding backslash (before `python`) is omitted.
:::

:::js
JavaScript/TypeScript-specific content. In real docs, the preceding backslash (before `js`) is omitted.
:::

Content for both languages (not wrapped)

This will generate two outputs (one for each language) at /oss/python/concepts/foo.mdx and /oss/javascript/concepts/foo.mdx. Each outputted page will need to be added to the /src/docs.json file to be included in the navigation.

Quality standards

General guidelines

Accessibility requirements

Ensure documentation is accessible to all users:

• Structure content for easy scanning with headers and lists
• Use specific, actionable link text instead of "click here"
• Include descriptive alt text for all images and diagrams

Cross-referencing

Use consistent cross-references to connect docs with API reference documentation.

From docs to API reference:

Use the @[] syntax to link to API reference pages:

See @[`ChatAnthropic`] for all configuration options.

The @[`bind_tools`][ChatAnthropic.bind_tools] method accepts...

The build pipeline transforms these into proper markdown links based on the current language scope (Python or JavaScript). For example, @[ChatAnthropic] becomes a link to the Python or JS API reference page depending on which version of the docs is being built, but only if an entry exists in the link_map.py file! See below for details.

From API reference stubs to OSS docs:

Cross-links and deep anchors in the published Python API reference are generated outside this repository. If a link from reference.langchain.com to docs.langchain.com is wrong or outdated, open an issue with the source and destination URLs.

Localization

Where a feature exists in both SDKs, document it for Python and JavaScript/TypeScript together. If only one language is supported yet, ensure the feature and references to it are only visible for that language.

In-code documentation

Examples must be correct, copy-pasteable where possible, and tested before you open a pull request. Mark non-runnable snippets clearly (for example, pseudocode or illustrative fragments).

Get help

Our goal is to have the simplest developer setup possible. Should you experience any difficulty getting setup, please ask in the community slack or open a forum post. Internal team members can reach out in the #documentation Slack channel.