github.com/protomcp/protomcp

protomcp

[!WARNING] This project is still in the design phase and not ready for production use. APIs and architecture may change significantly.

A modular protoc generator framework for creating combined JSON-RPC 2.0 and MCP (Model Context Protocol) endpoints from .proto service definitions, supporting HTTP/2 and QUIC transport protocols.

Overview

protomcp generates Go code that provides unified interfaces for services defined in Protocol Buffer (.proto) files, enabling them to serve both JSON-RPC 2.0 and Anthropic's Model Context Protocol (MCP) over modern transport protocols. The generator prioritizes interface-based design for modularity and loose coupling.

Key Features

• Dual Protocol Support: Generate unified endpoints for JSON-RPC 2.0 and MCP.
• Modern Transports: HTTP/2 and QUIC protocol support.
• Interface-First Design: Prioritizes interfaces over concrete structs for maximum modularity.
• Schema Validation: Integrated JSON Schema generation and validation.
• Protobuf Integration: Works with existing .proto service definitions.
• Sourcegraph jsonrpc2: Built on proven JSON-RPC 2.0 foundation.

Architecture

The project follows a modular architecture with clear separation of concerns:

• Generator Package: Core protoc plugin for code generation.
• Transport Layer: HTTP/2 and QUIC transport implementations.
• Protocol Layer: JSON-RPC 2.0 and MCP protocol handlers.
• Validation Layer: JSON Schema validation and type safety.
• Interface Layer: Service interfaces independent of concrete protobuf types.

Dependencies

• Go 1.23+: Modern Go version for latest features.
• sourcegraph/jsonrpc2: Proven JSON-RPC 2.0 implementation.
• Protocol Buffers: For service definition parsing.
• JSON Schema: For request/response validation.
• HTTP/2 & QUIC: Modern transport protocol support.

Project Structure

protomcp/
├── cmd/                    # CLI tools and protoc plugins
├── pkg/protomcp/          # Core library code
├── internal/build/        # Build system and tooling
└── examples/              # Usage examples and demos

Development Status

🚧 DESIGN PHASE - NOT PRODUCTION READY 🚧

This project is currently in active design and early development. Nothing is stable yet and everything may change. The initial focus is on:

• Core generator framework.
• Interface design patterns.
• JSON-RPC 2.0 foundation.
• MCP protocol integration.
• Transport layer abstraction.

Do not use this in production environments.

Contributing

See AGENT.md for development guidelines and build system details.

License

This project is licensed under the MIT License—see the LICENCE.txt file for details.