CRAN Package README MCP Server

An MCP (Model Context Protocol) server that enables AI assistants to fetch comprehensive information about CRAN (Comprehensive R Archive Network) packages, including README content, package metadata, and search functionality.

Features

• Package README Retrieval: Fetch formatted README content with usage examples from R/CRAN packages hosted on CRAN repository
• Package Information: Get comprehensive package metadata including dependencies, versions, maintainer information, and documentation
• Package Search: Search CRAN repository with filtering by category, topic, and popularity
• Smart Caching: Intelligent caching system to optimize API usage and improve response times
• GitHub Integration: Seamless integration with GitHub API for enhanced README fetching from package repositories
• Error Handling: Robust error handling with automatic retry logic and fallback strategies

MCP Client Configuration

Add this server to your MCP client configuration:

{
  "mcpServers": {
    "cran-package-readme": {
      "command": "npx",
      "args": ["cran-package-readme-mcp-server"],
      "env": {
        "GITHUB_TOKEN": "your_github_token_here"
      }
    }
  }
}

Note: The GITHUB_TOKEN is optional but recommended for higher API rate limits when fetching README content from GitHub.

Available Tools

get_package_readme

Retrieves comprehensive README content and usage examples for CRAN packages.

Parameters:

{
  "package_name": "ggplot2",
  "version": "latest",
  "include_examples": true
}

• package_name (string, required): CRAN package name (e.g., "ggplot2", "dplyr")
• version (string, optional): Specific package version or "latest" (default: "latest")
• include_examples (boolean, optional): Include usage examples and code snippets (default: true)

Returns: Formatted README content with installation instructions, usage examples, and function documentation.

get_package_info

Fetches detailed package metadata, dependencies, and maintainer information from CRAN.

Parameters:

{
  "package_name": "dplyr",
  "include_dependencies": true,
  "include_dev_dependencies": false
}

• package_name (string, required): CRAN package name
• include_dependencies (boolean, optional): Include runtime dependencies (default: true)
• include_dev_dependencies (boolean, optional): Include development dependencies (default: false)

Returns: Package metadata including version info, maintainer details, license, download stats, and dependency information.

search_packages

Searches CRAN repository for packages with filtering capabilities.

Parameters:

{
  "query": "machine learning",
  "limit": 20,
  "category": "MachineLearning"
}

• query (string, required): Search terms (package name, description, keywords)
• limit (number, optional): Maximum number of results to return (default: 20, max: 100)
• category (string, optional): Filter by package category (Graphics, Statistics, MachineLearning, etc.)

Returns: List of matching packages with names, descriptions, maintainers, and popularity metrics.

Error Handling

The server handles common error scenarios gracefully:

• Package not found: Returns clear error messages with similar package suggestions
• Rate limiting: Implements automatic retry with exponential backoff
• Network timeouts: Configurable timeout with retry logic
• Invalid package names: Validates package name format and provides guidance
• CRAN mirror failures: Fallback strategies when primary CRAN mirror is unavailable

License

MIT