Ruby MCP Server Generator

Ruby MCP Server Generator

ruby-mcp-server-generator skill for programming & development

Category: development Source: github

An AI skill that generates Ruby based Model Context Protocol servers, scaffolding the full project structure with tool definitions, resource handlers, and transport configuration so developers can expose Ruby services to AI assistants quickly.

What Is This?

Overview

This skill creates complete Ruby MCP server projects from a description of the tools and resources you want to expose. It generates the server entry point, tool handler classes, resource definitions, JSON schema validation, and transport layer setup for both stdio and HTTP streaming. The output follows Ruby conventions including Bundler for dependency management, structured class hierarchies, and idiomatic error handling. Developers get a working MCP server they can extend immediately.

Who Should Use This

Designed for Ruby developers who want to integrate their services with AI assistants via MCP. Ideal for teams with existing Ruby APIs, Rails applications, or command line tools that would benefit from AI assistant integration. Also useful for developers prototyping MCP tools who prefer Ruby over other languages.

Why Use It?

Problems It Solves

Building an MCP server from scratch requires understanding the protocol specification, implementing transport layers, handling JSON-RPC message framing, and managing tool registration. Doing this in Ruby means writing boilerplate for class structures, Gemfile dependencies, and proper signal handling. This skill eliminates that setup time by generating a complete, working server.

Core Highlights

  • Full Project Scaffold generates Gemfile, entry point, tool classes, and configuration
  • Transport Support configures both stdio and HTTP streaming transports
  • Schema Validation includes JSON schema definitions for tool inputs
  • Ruby Conventions follows standard gem structure and naming patterns
  • Test Stubs generates RSpec test files for each tool handler

How to Use It?

Basic Usage

Describe the tools you want your MCP server to expose and the skill generates the full project.

module MyServer
  module Tools
    class SearchDocs
      SCHEMA = {
        type: "object",
        properties: {
          query: { type: "string", description: "Search query" },
          limit: { type: "integer", default: 10 }
        },
        required: ["query"]
      }.freeze

      def call(params)
        results = DocumentIndex.search(params[:query], limit: params[:limit])
        { results: results.map(&:to_h) }
      end
    end
  end
end

Real-World Examples

Rails Integration MCP Server

A team with an existing Rails application generated an MCP server that exposed their database queries and business logic as AI tools. The generated server included tools for searching customers, retrieving order history, and generating reports, all backed by their existing ActiveRecord models.

require "mcp"
require_relative "lib/tools/search_customers"
require_relative "lib/tools/order_history"

server = MCP::Server.new(name: "rails-bridge", version: "1.0.0")

server.register_tool("search_customers",
  description: "Search customers by name or email",
  schema: Tools::SearchCustomers::SCHEMA,
  handler: Tools::SearchCustomers.new
)

server.register_tool("order_history",
  description: "Get order history for a customer",
  schema: Tools::OrderHistory::SCHEMA,
  handler: Tools::OrderHistory.new
)

server.run(transport: :stdio)

Advanced Tips

Use the generated RSpec stubs as a starting point for thorough testing. Mock external dependencies in tool handlers to keep tests fast. When connecting to Rails models, extract a thin service layer rather than coupling MCP tool handlers directly to ActiveRecord to maintain clean separation.

When to Use It?

Use Cases

  • Rails API Bridge expose existing Rails functionality to AI assistants
  • CLI Tool Wrapper wrap Ruby command line tools as MCP services
  • Data Pipeline Access let AI assistants query Ruby based ETL pipelines
  • DevOps Automation expose infrastructure management scripts via MCP
  • Prototype Tooling quickly test MCP tool ideas using familiar Ruby syntax

Related Topics

When working with Ruby MCP servers, these prompts activate the skill:

  • "Generate a Ruby MCP server for my tools"
  • "Create an MCP server in Ruby"
  • "Scaffold a Ruby MCP project"
  • "Build a Ruby server for AI tool integration"

Important Notes

Requirements

  • Ruby 3.1 or later recommended for full language feature support
  • Bundler for dependency management with generated Gemfile
  • An MCP compatible AI assistant or client for testing the server
  • Standard Unix environment for stdio transport or HTTP server for streaming

Usage Recommendations

Do:

  • Review generated schemas to ensure they match your actual data types
  • Add authentication before exposing any sensitive operations
  • Write tests for custom tool logic beyond the generated stubs
  • Use environment variables for configuration like database URLs and API keys

Don't:

  • Expose database writes without proper authorization checks
  • Skip input validation even though schemas provide basic type checking
  • Deploy without rate limiting as AI assistants can generate many rapid requests
  • Couple tool handlers to frameworks directly since use a service layer instead

Limitations

  • Generated servers require manual integration with existing Ruby application code
  • Complex tool interactions with state management need custom implementation
  • The MCP Ruby ecosystem is newer than Python or TypeScript with fewer community libraries
  • Performance tuning for high throughput scenarios requires additional configuration