What is Mcp Wasm

mcp-wasm is a repository that provides Model Context Protocol (MCP) interface definitions in WIT format for the WebAssembly Component Model. It enables secure and portable implementations of MCP functionalities within a sandboxed WebAssembly environment.

Use cases

Use cases for mcp-wasm include deploying language models in a secure manner within web applications, providing context to LLMs without exposing sensitive resources, and creating portable applications that leverage the Model Context Protocol in a sandboxed WebAssembly runtime.

How to use

To use mcp-wasm, developers can integrate the provided WIT interface definitions into their WebAssembly projects, ensuring that the MCP functionalities are executed in a secure, sandboxed environment. Caution is advised as the project is under heavy development.

Key features

Key features of mcp-wasm include a sandbox environment for fine-grained control over resource access, language independence allowing use of any programming language that compiles to WebAssembly, and enhanced security by mitigating risks associated with unrestricted access in traditional MCP implementations.

Where to use

mcp-wasm can be used in various fields including web development, cloud computing, and any application that requires secure execution of large language models (LLMs) in a controlled environment.

Model Context Protocol in WebAssembly Components

[!WARNING]
This project is under heavy development, and all interfaces are subject to change at any moment without prior notice. Use with caution in production environments.

Introduction

This project adapts the Model Context Protocol (MCP) to operate within the sandboxed environment of WebAssembly Components. MCP is an open protocol that standardizes how applications provide context to large language models (LLMs).

The original MCP specification focuses on two primary environments:

• Remote execution: where the MCP server communicates via WebSocket.
• Local execution: where the MCP server runs as a standard program and communicates over standard input/output (stdio).

Motivation

While the original MCP specification provides a flexible way to deploy context providers, it also introduces potential security concerns. These concerns are highlighted in the official MCP documentation, which notes risks associated with unrestricted access and execution capabilities of MCP servers. Specifically, running an MCP server in its standard environments may:

• permit unlimited network access,
• allow full disk access,

Currently, MCP officially supports only three programming languages: Python, TypeScript, and Kotlin. While there are additional unofficial implementations in other languages, the quality of these implementations varies.

Goals and Benefits

This project proposes a solution to address these security concerns: running the MCP server in sandboxed environment provided by a WebAssembly runtime. This approach provides:

• A sandbox environment: This allows fine-grained control over access to computer resources. For example, you can specify what IP addresses are allowed or which files are available at the runtime level. This ensures that downloaded code never has unrestricted access to your computer.
• Language independence: Developers can use any programming language that compiles to WebAssembly, significantly expanding flexibility and enabling broader adoption.
• Backward compatibility with classical MCP servers: By supporting the WebAssembly System Interface (WASI), this solution can be easily adapted to run as a traditional MCP server, with the added benefits of sandboxing.
• Portability: WebAssembly is platform-agnostic, allowing the same MCP server to run seamlessly across different environments.

What This Repository Contains

This repository contains interface definitions, in the format of WIT files, for the WebAssembly Component Model. These interfaces aim to provide a compatible API to the original MCP by recreating each of its aspects.

License

This project is licensed under the MIT License.