
BundlerMCP
Enables agents to query information about gems in a Ruby project's Gemfile, including source code and metadata.
README
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
- Generate the binstub:
bundle binstubs bundler_mcp
- 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 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
andCHANGELOG
)
get_gem_details
Retrieves detailed information about a specific gem, including:
- Version
- Description
- Installation path
- Top-level documentation locations
- Source code file locations
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:
- Update the version number in
version.rb
- 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
Recommended Servers
playwright-mcp
A Model Context Protocol server that enables LLMs to interact with web pages through structured accessibility snapshots without requiring vision models or screenshots.
Magic Component Platform (MCP)
An AI-powered tool that generates modern UI components from natural language descriptions, integrating with popular IDEs to streamline UI development workflow.
Audiense Insights MCP Server
Enables interaction with Audiense Insights accounts via the Model Context Protocol, facilitating the extraction and analysis of marketing insights and audience data including demographics, behavior, and influencer engagement.

VeyraX MCP
Single MCP tool to connect all your favorite tools: Gmail, Calendar and 40 more.
graphlit-mcp-server
The Model Context Protocol (MCP) Server enables integration between MCP clients and the Graphlit service. Ingest anything from Slack to Gmail to podcast feeds, in addition to web crawling, into a Graphlit project - and then retrieve relevant contents from the MCP client.
Kagi MCP Server
An MCP server that integrates Kagi search capabilities with Claude AI, enabling Claude to perform real-time web searches when answering questions that require up-to-date information.

E2B
Using MCP to run code via e2b.
Neon Database
MCP server for interacting with Neon Management API and databases
Exa Search
A Model Context Protocol (MCP) server lets AI assistants like Claude use the Exa AI Search API for web searches. This setup allows AI models to get real-time web information in a safe and controlled way.
Qdrant Server
This repository is an example of how to create a MCP server for Qdrant, a vector search engine.