AI product Open source
wasmcp is a WebAssembly Component Development Kit and CLI for building Model Context Protocol (MCP) servers. It scaffolds MCP tool components in Rust, Python, or TypeScript, registers local or OCI-distributed components under aliases, and composes them into a WebAssembly server that can run with Wasmtime, Spin, or another component-capable runtime.
Its composition pipeline wraps tool, resource, prompt, and other MCP feature components with transport and middleware components. Each component handles the requests it understands and delegates the rest downstream; results such as tool lists are merged into a unified server catalog. The CLI also supports reusable composition profiles, stateful sessions backed by key-value storage, streaming notifications, and public or OAuth 2.1-protected operation with JWT bearer-token validation and scope-based authorization.
The project is distributed as an installable CLI or can be built with Cargo. Its generated servers use WebAssembly components and the project is licensed under Apache 2.0.
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A CLI that integrates with Spin for building MCP servers. It scaffolds tools, resources, and prompts in TypeScript, Rust, or Python and composes them, along with off-the-shelf components for things like authentication, into a full MCP server WebAssembly component.
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