📌Overview

Purpose: To provide a Ruby implementation of a Model Context Protocol (MCP) server that enables Large Language Models (LLMs) to interact with Rails projects effectively.

Overview: The Rails MCP Server is designed to facilitate seamless communication between AI models and Rails applications by implementing the Model Context Protocol. This standardized protocol allows AI models to perform tasks such as code analysis and exploration within Rails projects.

Key Features:

Manage Multiple Projects: Supports interaction with multiple Rails projects, allowing users to switch between them seamlessly.
Project File Exploration: Users can browse, list, and inspect files within a Rails project to analyze its structure and content.
Access to Rails Routes and Models: Retrieve detailed information about defined routes and Active Record models, including schema, associations, and definitions.
Database Schema Retrieval: Fetch schema information for the entire database or specific tables, enhancing understanding of the project’s database design.
MCP Compliance: Adheres to the Model Context Protocol standard, ensuring compatibility with various LLM clients.

Rails MCP Server

A Ruby implementation of a Model Context Protocol (MCP) server for Rails projects. This server allows LLMs (Large Language Models) to interact with Rails projects through the Model Context Protocol.

What is MCP?

The Model Context Protocol (MCP) is a standardized method for AI models to interact with their environment. It defines a way for models to request and use tools, access resources, and maintain context during interactions.

Features

Manage multiple Rails projects
Browse project files and structures
View Rails routes
Inspect model information
Get database schema information
Follow the Model Context Protocol standard

Installation

Install the gem:

gem install rails-mcp-server

After installation, the rails-mcp-server and rails-mcp-setup-claude executables will be available in your PATH.

Configuration

The Rails MCP Server follows the XDG Base Directory Specification for configuration files:

macOS: $XDG_CONFIG_HOME/rails-mcp or ~/.config/rails-mcp
Windows: %APPDATA%\rails-mcp

To configure your projects, edit the projects.yml file:

store: "~/projects/store"
blog: "~/projects/rails-blog"

Claude Desktop Integration

The Rails MCP Server can be configured with Claude Desktop using one of the following options:

Option 1: Setup Script

Run the setup script:

rails-mcp-setup-claude

Option 2: Manual Configuration

Create the appropriate config directory.
Create a projects.yml file in that directory.
Update the Claude Desktop configuration file.

Ruby Version Manager Users

Ensure the MCP server uses the same Ruby version as it was installed by creating a symbolic link to your Ruby shim.

Usage

Start the server:

rails-mcp-server

Logging Options

Customize logging with these options:

rails-mcp-server --log-level debug

How the Server Works

The Rails MCP Server implements the Model Context Protocol over standard input/output (stdio), processing JSON-RPC 2.0 requests and returning responses.

Available Tools

1. `switch_project`

Description: Change the active Rails project.

2. `get_project_info`

Description: Retrieve information about the current Rails project.

3. `list_files`

Description: List files in the Rails project.

4. `get_file`

Description: Get the content of a file in the Rails project.

5. `get_routes`

Description: Get the routes defined in the Rails project.

6. `get_models`

Description: Get information about the models in the Rails project.

7. `get_schema`

Description: Get the database schema for the Rails project.

Integration with LLM Clients

To integrate with LLM clients:

Start the Rails MCP Server.
Connect your MCP-compatible client to the server.

Manual Testing

You can manually test the server by sending JSON-RPC requests. For example:

echo '0 {"jsonrpc":"2.0","id":"test-123","method":"ping"}' | rails-mcp-server

License

This Rails MCP server is released under the MIT License, allowing free use, modification, and distribution.

Contributing

Bug reports and pull requests are welcome on GitHub at rails-mcp-server.

rails-mcp-server