A Private Monorepo of MCP Reference Servers
A private monorepo collecting Model Context Protocol reference server implementations, giving LLMs secure and controlled access to tools and data sources.
This is a private monorepo of Model Context Protocol servers, collecting reference implementations alongside pointers to community-built servers and other resources. The point of MCP, and the point of having a stable of these servers on hand, is to give large language models secure, controlled access to tools and data sources instead of letting them reach into systems ad hoc.
Why keep a collection
MCP is an interface, and interfaces are best understood by reading many implementations rather than one. Each server in the collection demonstrates a different capability while sharing the same protocol shape. Having them together in one monorepo means the patterns are side by side, which is how you actually learn where the protocol is flexible and where the conventions have settled.
Most servers are built with one of the MCP SDKs, and the ecosystem now spans a wide set of languages: C#, Go, Java, Kotlin, Python, Ruby, Rust, Swift, and TypeScript. That breadth is worth noticing on its own. A protocol with real SDK coverage in nine languages is one you can adopt from wherever your stack already lives, rather than being forced onto someone else's runtime.
The reference servers
The reference set is the useful core, each one demonstrating MCP features against the official SDKs. Everything is a test server exercising prompts, resources, and tools. Fetch handles web content retrieval and conversion into a form that is efficient for an LLM to consume. Filesystem provides secure file operations with configurable access controls. Git exposes tools to read, search, and manipulate repositories. Memory is a knowledge-graph-based persistent memory system. There is a Sequential Thinking server in the set as well.
The through-line across those is "secure and controlled." Filesystem does not just do file operations, it does them behind configurable access controls. That is the whole ethos of MCP done right. The interesting part is never that a model can touch a resource, it is that the touching is scoped and governed.
One small operational note that reflects how this repo is maintained: the lists in the README are kept in alphabetical order deliberately, to minimize merge conflicts when new servers get added. It is a tiny discipline, but in a monorepo that many people append to, ordering by a rule instead of by whim is the difference between clean additions and constant churn.
The takeaway I keep from working with MCP is that the value is in the boundary, not the capability. Any tool can read a file or hit a URL. What makes these servers worth collecting is that they define exactly what the model may do and under what controls, and that boundary is the real product.
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