rs-docsrs-mcp

A Model Context Protocol (MCP) server for docs.rs - enabling AI assistants to search and fetch Rust crate documentation.

Features

• 🔍 Search Crates: Search for Rust crates on docs.rs by name or keyword
• 📦 Crate Information: Get detailed information about specific crates
• 📚 Documentation Access: Fetch documentation for specific modules, structs, functions, and more
• 📑 Module Listing: List all modules, structs, enums, functions, traits, and macros in a crate
• 📖 README Access: Retrieve crate README and metadata
• 📋 Version History: List all available versions of a crate
• 🔄 Reverse Dependencies: Find which crates depend on a specific crate
• 📊 Download Stats: Get download statistics from crates.io
• 🎯 Item Search: Search for specific item types within a crate
• 🔗 Source Links: Get repository and source code links
• ⚙️ Feature Discovery: Find crate features and configuration options
• 📦 Direct Dependencies: Get all dependencies of a crate
• 👥 Crate Owners: Get crate maintainers and owners
• 🦀 Rustdoc Search: Search across all crates for a symbol or type
• 📅 Release History: Get crate release history with dates
• 🔍 Trait Implementations: Find all implementations of a trait
• 💻 Source Code: View source code for any item
• 🏷️ Keywords/Categories: Get crate keywords and categories
• 📄 License Info: Get crate license information
• ⚖️ Version Comparison: Compare items between two versions

Installation

Install globally via npm:

npm install -g rs-docsrs-mcp

Or use with npx:

npx rs-docsrs-mcp

Usage with Claude Desktop

Add to your Claude Desktop configuration file:

MacOS: ~/Library/Application Support/Claude/claude_desktop_config.json

Windows: %APPDATA%\Claude\claude_desktop_config.json

{
  "mcpServers": {
    "docsrs": {
      "command": "npx",
      "args": ["-y", "rs-docsrs-mcp"]
    }
  }
}

If installed globally:

{
  "mcpServers": {
    "docsrs": {
      "command": "rs-docsrs-mcp"
    }
  }
}

Available Tools

1. docs_rs_search

Search for crates on docs.rs.

Parameters:

• query (string, required): Crate name or keyword to search
• limit (number, optional): Maximum number of results (1-50, default: 10)

Example:

{
  "query": "tokio",
  "limit": 5
}

2. docs_rs_crate_home

Get homepage information for a specific crate.

Parameters:

• crate (string, required): Crate name

Example:

{
  "crate": "tokio"
}

3. docs_rs_get_doc

Get documentation for a specific path in a crate.

Parameters:

• crate (string, required): Crate name
• version (string, optional): Version (default: "latest")
• path (string, optional): Documentation path (e.g., "tokio/runtime/index.html")

Examples:

{
  "crate": "tokio",
  "version": "latest",
  "path": "tokio/runtime/struct.Runtime.html"
}

{
  "crate": "serde",
  "path": "serde/trait.Serialize.html"
}

4. docs_rs_list_modules

List all modules and items in a crate.

Parameters:

• crate (string, required): Crate name
• version (string, optional): Version (default: "latest")

Example:

{
  "crate": "tokio",
  "version": "1.35.0"
}

Returns:

• modules: List of modules with descriptions
• structs: List of structs
• enums: List of enums
• functions: List of functions
• traits: List of traits
• macros: List of macros

5. docs_rs_get_readme

Get README and metadata for a crate.

Parameters:

• crate (string, required): Crate name
• version (string, optional): Version (default: "latest")

Example:

{
  "crate": "tokio"
}

6. docs_rs_list_versions

List all available versions of a crate.

Parameters:

• crate (string, required): Crate name

Example:

{
  "crate": "tokio"
}

Returns:

• versions: Array of version strings (sorted descending)
• latest_url: URL to the latest version docs

7. docs_rs_get_reverse_deps

Get reverse dependencies (which crates depend on this crate).

Parameters:

• crate (string, required): Crate name

Example:

{
  "crate": "tokio"
}

8. docs_rs_get_downloads

Get download statistics for a crate from crates.io.

Parameters:

• crate (string, required): Crate name

Example:

{
  "crate": "tokio"
}

Returns:

• downloads: Object with all (total) and recent download counts
• latest_version: Latest version number
• created_at, updated_at: Timestamps

9. docs_rs_search_items

Search for specific item types within a crate.

Parameters:

• crate (string, required): Crate name
• version (string, optional): Version (default: "latest")
• item_type (string, optional): Item type to filter by (mod, struct, enum, fn, trait, macro, type, constant)

Example:

{
  "crate": "tokio",
  "item_type": "trait"
}

Returns:

• items: Array of items with name, kind, description, and path

10. docs_rs_get_source_link

Get source code link and repository information for a crate.

Parameters:

• crate (string, required): Crate name
• version (string, optional): Version (default: "latest")

Example:

{
  "crate": "serde"
}

Returns:

• repository: GitHub/GitLab repository URL
• source_url: Direct source code link
• download_url: Crate download URL

11. docs_rs_get_features

Get crate features and configuration options.

Parameters:

• crate (string, required): Crate name
• version (string, optional): Version (default: "latest")

Example:

{
  "crate": "tokio",
  "version": "1.35.0"
}

Returns:

• features: Array of feature names
• has_features: Boolean indicating if features were found

12. docs_rs_get_dependencies

Get direct dependencies of a crate.

Parameters:

• crate (string, required): Crate name
• version (string, optional): Version (default: "latest")

Example:

{
  "crate": "tokio",
  "version": "1.35.0"
}

13. docs_rs_get_owners

Get crate owners and maintainers from crates.io.

Parameters:

• crate (string, required): Crate name

Example:

{
  "crate": "serde"
}

14. docs_rs_search_rustdoc

Search rustdoc across crates for a symbol or type.

Parameters:

• query (string, required): Search query for symbol or type
• limit (number, optional): Maximum results (default: 10)

Example:

{
  "query": "Runtime",
  "limit": 5
}

15. docs_rs_get_releases

Get crate release history with dates.

Parameters:

• crate (string, required): Crate name
• limit (number, optional): Maximum releases (default: 20)

Example:

{
  "crate": "tokio",
  "limit": 10
}

16. docs_rs_get_trait_impls

Find all implementations of a trait in a crate.

Parameters:

• crate (string, required): Crate name
• trait_name (string, optional): Name of the trait to search for
• version (string, optional): Version (default: "latest")

Example:

{
  "crate": "tokio",
  "trait_name": "Future"
}

17. docs_rs_get_source_code

Get source code for a specific item.

Parameters:

• crate (string, required): Crate name
• version (string, optional): Version (default: "latest")
• path (string, required): Documentation path to the item

Example:

{
  "crate": "serde",
  "version": "latest",
  "path": "serde/ser/trait.Serialize.html"
}

18. docs_rs_get_keywords

Get crate keywords and categories from crates.io.

Parameters:

• crate (string, required): Crate name

Example:

{
  "crate": "actix-web"
}

19. docs_rs_get_license

Get crate license information.

Parameters:

• crate (string, required): Crate name

Example:

{
  "crate": "tokio"
}

20. docs_rs_compare_versions

Compare two versions of a crate.

Parameters:

• crate (string, required): Crate name
• version1 (string, required): First version to compare
• version2 (string, required): Second version to compare

Example:

{
  "crate": "tokio",
  "version1": "1.30.0",
  "version2": "1.35.0"
}

Returns:

• version1_items: Item counts for version 1
• version2_items: Item counts for version 2
• comparison: Diff for each item type

Example Queries

Once configured, you can ask Claude:

• "Search for HTTP client crates"
• "Show me the tokio runtime documentation"
• "List all modules in the serde crate"
• "Get the README for actix-web"
• "What structs are available in tokio?"

Development

Clone the repository:

git clone https://github.com/lazhenyi/rs-docsrs-mcp.git
cd rs-docsrs-mcp
npm install

Run locally:

npm start

Requirements

• Node.js >= 20.0.0

How It Works

This MCP server scrapes documentation from docs.rs to provide structured information about Rust crates. It uses:

• cheerio: For HTML parsing
• node-fetch: For HTTP requests
• @modelcontextprotocol/sdk: For MCP protocol implementation
• zod: For parameter validation

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

MIT License - see the LICENSE file for details.

Links

• GitHub Repository
• npm Package
• Model Context Protocol
• docs.rs

Support

If you encounter any issues or have questions, please open an issue on GitHub.