Kuri

🚀 Kuri

kuri is a framework for building Model Context Protocol (MCP) servers, focusing on developer experience and code clarity.

MCP allows large language models (LLMs) to execute predefined functions (known as "tools"), which can be used to fetch data and perform side - effects (i.e., interact with the external world). The LLM only needs to provide the input parameters of the function, then the function is executed, and the result is returned to the model. These tools are provided by "MCP servers", which can run locally, and a single server can offer multiple tools.

🚀 Quick Start

What is MCP

MCP allows large language models (LLMs) to execute predefined functions (known as "tools"). These tools can fetch data and perform side - effects, interacting with the external world. The LLM provides input parameters, the function is executed, and the result is returned to the model. MCP servers, which can run locally, can offer multiple tools.

Why Kuri

Rust is an ideal language for writing reliable MCP servers due to its powerful type system and correctness guarantees. kuri aims to make it extremely enjoyable to write MCP servers in Rust, promoting the use of Rust for building MCP servers.

✨ Features

Design Philosophy

• Developer - friendly experience: Programming MCP servers should be as intuitive as regular Rust programming.
• Minimal use of macros (#[tool], #[prompt]): Only used for attaching tool and parameter descriptions, not for complex code generation.
• Reduced boilerplate code: Focus on application logic rather than serialization or MCP protocol routing.
• Leverage the tower ecosystem to provide support for transports, services, and middleware.

Core Features

• [x] Core lifecycle: Connection initialization, capability negotiation, and session control
• [x] Tools: Fully functional and tested
• [x] Prompts: Mostly completed and tested
• [ ] Resources
• Transports:
  • [x] Standard input/output (StdioTransport)
  • [ ] Streamable HTTP (2025 - 03 - 26 protocol)
• Optional features:
  • [ ] Autocompletion
  • [ ] Pagination

🔧 Technical Details

Current Priorities

The current priorities are to add HTTP transport support, stabilize the API, and ensure full compliance with the core specification.

🤝 Contribution

The goal of this project is to build a pleasant, friendly, and Rust - idiomatic MCP server library. It is still in the early stages, and there is room for structural adjustments. If you are interested in Rust, MCP, building crates, or network protocols (maybe you're interested in protohackers), we welcome your participation! Open an issue in the repository or contact us via email.

If you try to use this framework for project development: Thank you for trying it out! I'd love to hear about your experience!