list_project_gemsLABSCO SUMMARY
An agent can check the version you actually have before writing code against it.
It closes the gap between what a model remembers about a gem and what your lockfile resolved: the versions are yours, and the paths let it read the installed source and CHANGELOG rather than recall an API.
What it is
A Ruby gem that runs as an MCP server over your project's Gemfile. It reports the gems Bundler resolved, with versions, descriptions, install paths and the location of each gem's README and CHANGELOG.
What you get
- Every bundled gem, with version, description, install path and top-level documentation locations
- One gem in detail, including where its source files live on disk
Requirements
Ruby, with the gem added to the development group and a binstub generated by bundle binstubs. Point your client at that binstub; an environment variable selects a different Gemfile when the binstub is not enough.
Setup effort
Follow the published steps — bundle add bundler_mcp --group=development
USE CASES
01
Finding out which version of a gem the project is on
List the bundled gems, then open the one in question, so advice is written against the version you actually resolved.
02
Reading the real source instead of recalling the API
Take the install path from the gem detail and point the model at the installed files, rather than at its memory of the library.
03
Getting your bearings in an unfamiliar Ruby project
Read the whole dependency list with descriptions, so what the project is built on is visible in one pass.
04
Checking a gem's CHANGELOG before an upgrade
Take the documentation location from the detail call and read the CHANGELOG that shipped with the installed version.
2 tools
Listed in project docs. Your client may show a different list.
get_gem_detailsBEFORE YOU INSTALL
What to know first
Tools you get
2 tools named in the project's documentation.
Requires
Ruby and Bundler, in a project with a Gemfile
Where it runs
The documented client runs the server on your machine.
INSTALLATION
Connect your client
Server setup
TERMINAL
bundle add bundler_mcp --group=development
bundle binstubs bundler_mcpPoint your MCP client at the generated bin/bundler_mcp binstub using the configuration under MCP Clients
MCP Clients
Any MCP client
ANY MCP CLIENT · JSON
{
"mcpServers": {
"bundler-mcp": {
"command": "/Users/mike/my_project/bin/bundler_mcp"
}
}
}
