Rust Docs

🚀 MCP Rust Documentation Server

This is a Model Context Protocol (MCP) server designed to retrieve and return documentation for Rust crates, providing the necessary context information for LLMs when processing Rust code.

🚀 Quick Start

This server is a practical tool for LLMs processing Rust code, offering essential context by retrieving and formatting Rust crate documentation.

✨ Features

• Retrieve documentation for any Rust crate available on docs.rs.
• Remove HTML and format the content for easy reading.
• Limit the response size to prevent overwhelming the client.
• Utilize the latest version of the MCP SDK (v1.6.1).

📦 Installation

# Clone the repository
git https://github.com/0xKoda/mcp-rust-docs.git
cd mcp-rust-docs

# Install dependencies
npm install

Prerequisites

• Node.js
• npm

💻 Usage Examples

Basic Usage

# Start the server directly
npm start

Integration with AI Assistants

Claude Desktop

Add the following content to the Claude Desktop configuration file (claude_desktop_config.json):

{
  "mcpServers": {
    "rust-docs": {
      "command": "node",
      "args": ["/absolute/path/to/index.js"]
    }
  }
}

Replace /absolute/path/to/index.js with the absolute path to the index.js file in this repository.

Example Usage

Once the server is running and your AI assistant is configured, you can ask questions like:

• "Find the documentation for the 'tokio' crate."
• "What features does the 'serde' crate provide?"
• "Show the documentation for 'ratatui'."
• "Can you explain the main modules of the 'axum' crate?" The AI will use the lookup_crate_docs tool to retrieve and display the relevant documentation.

Testing with MCP Inspector

You can test this server by running the following command:

npx @modelcontextprotocol/inspector

Then select the "Connect to a local server" option and follow the prompts.

🔧 Technical Details

How It Works

This server implements a single MCP tool named lookup_crate_docs, which performs the following steps:

1. Receive a Rust crate name as input (optional, defaults to 'tokio' if not provided).
2. Retrieve the documentation from docs.rs.
3. Convert the HTML to plain text using the html-to-text library.
4. Truncate the content if it exceeds 8000 characters.
5. Return the formatted documentation in the correct MCP response format.

SDK Implementation Notes

This server uses the MCP SDK with carefully structured import paths. If you are modifying the code, note the following:

1. The SDK needs to be imported from a specific path (e.g., @modelcontextprotocol/sdk/server/mcp.js).
2. We use the high-level McpServer API instead of the low-level tools.
3. Tool definitions use Zod for parameter validation.
4. Redirect console output to stderr to avoid breaking the MCP protocol.
5. Tools return the correct MCP response object.

🤝 Contribution

Contributions are welcome! Feel free to submit pull requests.

📄 License

MIT