Overview

MCProto is a lightweight Ruby framework that turns any Ruby class into a fully‑featured MCP (Model Context Protocol) server. It addresses the common pain point of wiring multiple AI‑driven services together by providing a simple, declarative syntax for defining resources, tools, and chains of operations. Developers can expose business logic, database queries, or external API calls as MCP endpoints with minimal boilerplate, enabling AI assistants like Claude to discover and invoke them directly within a conversation.

The core value of MCProto lies in its chainable architecture. Each server exposes a object that flows through the chain, allowing later steps to read data produced by earlier ones or augment the context with new information. This pattern mirrors how humans build up knowledge in a dialogue, making it natural for AI assistants to orchestrate complex workflows—such as validating user input, fetching related records, and sending notifications—all while maintaining a single, coherent conversation state.

Key features of MCProto include:

• Declarative resource definition – Specify the data model or API endpoint your server will expose, complete with metadata like name and description.
• Tool integration – Define lightweight operations that the AI can trigger based on context cues, such as detecting a user’s email address or checking for existing records.
• Chaining with – Compose multiple servers into a single logical flow, automatically passing context between them.
• Context‑aware execution – Each server can delegate methods to the shared context, enabling fine‑grained control over what data is available at each step.
• Open source and MIT licensed – Encourages community contributions and easy integration into existing Ruby on Rails or Sinatra projects.

Typical use cases for MCProto include:

• User onboarding pipelines – Detect when a new user signs up, validate their email, and send a personalized welcome invite.
• Dynamic content generation – Pull data from a database or external API, then generate tailored responses for an AI assistant.
• Workflow automation – Chain validation, transformation, and notification steps into a single MCP endpoint that an assistant can call with one request.

By exposing these capabilities as standard MCP servers, MCProto allows AI assistants to treat custom Ruby logic just like any other external tool. This seamless integration reduces friction for developers, accelerates the creation of AI‑enabled applications, and opens up new possibilities for building sophisticated, context‑aware conversational experiences.