Skip to main content
Glama

BundlerMCP

by subelsky
MIT License
13

BundlerMCP

A Model Context Protocol (MCP) server enabling AI agents to query information about dependencies in a Ruby project's Gemfile. Built with fast-mcp.

Installation

Install the gem and add to the application's Gemfile by executing:

bundle add bundler_mcp --group=development

Usage

  1. Generate the binstub:
bundle binstubs bundler_mcp
  1. Configure your client to execute the binstub. Here are examples that work for Claude and Cursor:

Basic Example (mcp.json)

{ "mcpServers": { "bundler-mcp": { "command": "/Users/mike/my_project/bin/bundler_mcp" } } }

Example with logging and explicit Gemfile

{ "mcpServers": { "bundler-mcp": { "command": "/Users/mike/my_project/bin/bundler_mcp", "env": { "BUNDLER_MCP_LOG_FILE": "/Users/mike/my_project/log/mcp.log", "BUNDLE_GEMFILE": "/Users/mike/my_project/subdir/Gemfile" } } } }

Documentation

Available on RubyDoc

Available Tools

The server provides two tools for AI agents:

list_project_gems

Lists all bundled Ruby gems with their:

  • Versions
  • Descriptions
  • Installation paths
  • Top-level documentation locations (e.g. README and CHANGELOG)

list_project_gems tool

get_gem_details

Retrieves detailed information about a specific gem, including:

  • Version
  • Description
  • Installation path
  • Top-level documentation locations
  • Source code file locations

get_gem_details tool

Environment Variables

  • BUNDLE_GEMFILE: Used by Bundler to locate your Gemfile. If you use the binstub method described in the Usage section, this is usually not needed.
  • BUNDLER_MCP_LOG_FILE: Path to log file. Useful for troubleshooting (defaults to no logging)

Development

After checking out the repo, run bin/setup to install dependencies and bundle exec rspec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

Testing with the MCP Inspector

You can test the server directly using the MCP inspector:

# Basic usage npx @modelcontextprotocol/inspector ./bin/bundler_mcp # With logging enabled BUNDLER_MCP_LOG_FILE=/tmp/log/mcp.log npx @modelcontextprotocol/inspector ./bin/bundler_mcp # With custom Gemfile BUNDLE_GEMFILE=./other/Gemfile npx @modelcontextprotocol/inspector ./bin/bundler_mcp

Release Process

To install this gem onto your local machine, run bundle exec rake install. To release a new version:

  1. Update the version number in version.rb
  2. Run bundle exec rake release

This will:

  • Create a git tag for the version
  • Push git commits and the created tag
  • Push the .gem file to rubygems.org

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/subelsky/bundler_mcp.

License

Open source under the terms of the MIT License.

Author

Mike Subelsky

-
security - not tested
A
license - permissive license
-
quality - not tested

Enables agents to query information about gems in a Ruby project's Gemfile, including source code and metadata.

  1. Installation
    1. Usage
      1. Basic Example (mcp.json)
      2. Example with logging and explicit Gemfile
      3. Documentation
      4. Available Tools
    2. Environment Variables
      1. Development
        1. Testing with the MCP Inspector
        2. Release Process
      2. Contributing
        1. License
          1. Author

            Related MCP Servers

            • A
              security
              F
              license
              A
              quality
              Enables interaction with the Metal Framework by providing documentation search and code generation capabilities using natural language queries.
              Last updated -
              2
              2
              TypeScript
            • A
              security
              A
              license
              A
              quality
              Provides tools for listing and retrieving content from different knowledge bases using semantic search capabilities.
              Last updated -
              2
              10
              TypeScript
              The Unlicense
              • Linux
              • Apple
            • -
              security
              A
              license
              -
              quality
              Provides programmatic search functionality for Obsidian vaults through a REST API interface, allowing external applications to search through notes and retrieve absolute paths to matching documents.
              Last updated -
              10
              Python
              MIT License
              • Apple
            • -
              security
              F
              license
              -
              quality
              A Model Context Protocol server that allows interaction with the RubyGems.org API to fetch metadata about Ruby packages, search gems, and explore dependencies and ownership information.
              Last updated -
              TypeScript
              • Apple

            View all related MCP servers

            MCP directory API

            We provide all the information about MCP servers via our MCP API.

            curl -X GET 'https://glama.ai/api/mcp/v1/servers/subelsky/bundler_mcp'

            If you have feedback or need assistance with the MCP directory API, please join our Discord server