rails-routes-mcp

Two MCP tools over a Rails route table. Ruby. Stdio.

RubyMine 2025.2+ is already an MCP server. This is the other direction: a small server the IDE’s assistant can attach as a client.

Design rule from JetBrains, Feb 2026: paginate, filter, return file and line. Don’t dump bin/rails routes.

Fifteen-route shop catalog so CI doesn’t need a Rails app.

Tools

Related MCP server: ACE-MCP

RubyMine

Settings → Tools → MCP Server → stdio:

{
  "mcpServers": {
    "rails-routes": {
      "command": "ruby",
      "args": ["/absolute/path/to/rails-routes-mcp/bin/rails-routes-mcp"]
    }
  }
}

Eval

ruby evals/run.rb

A full rails routes dump is 4.83× a typical shaped page. 8/8 queries can fill show_route from verb / path / file / line.

ruby -Itest test/catalog_test.rb test/server_test.rb

No Bundler. MRI 3.1. The official Ruby MCP SDK is the right move if you want HTTP inside Rails; this slice is stdio on purpose.

Demo

Live: https://01a05643-d6bf-7a9d-9634-4f367e3a2682.skydive.app/rails_routes_mcp

pip install -r requirements.txt
streamlit run app.py

MIT. Ashley Gross, 2026.