MCP Reference Servers

modelcontextprotocol/servers is the official reference-implementation repository for the Model Context Protocol, and at 89.3k stars and 11.4k forks it is the most-starred artifact in the MCP ecosystem — largely because it is the canonical answer to the question every new implementer has: what does a correct MCP server actually look like? It ships seven maintained reference servers, deliberately small and readable rather than feature-complete: Everything, a reference and test server exercising prompts, resources and tools together so client authors can validate their host; Fetch, web content fetching and conversion for efficient LLM usage; Filesystem, secure file operations with configurable access controls; Git, tools to read, search and manipulate Git repositories; Memory, a knowledge-graph-based persistent memory system; Sequential Thinking, dynamic and reflective problem-solving through thought sequences; and Time, time and timezone conversion. Roughly thirteen earlier servers — GitHub, GitLab, PostgreSQL, SQLite, Slack and others — are archived rather than deleted, which matters in practice because plenty of tutorials still link to them; those integrations are now maintained by their respective vendors. Implementations span TypeScript and Python, and both are runnable without cloning the repo: npx -y @modelcontextprotocol/server-memory for the Node servers, and uvx mcp-server-git or pip install mcp_server_git for the Python ones. The README is organised as Reference Servers, Getting Started, Creating Your Own Server, Learn More, Contributing, Releasing, Security, License, Community and Support, and it now directs discovery of third-party servers to the official MCP Registry rather than maintaining an in-repo community list. Licensed MIT for existing code, with new contributions under Apache-2.0.

Topic

MCP

Level

All Levels

Format

Documentation

Cost

Free

Duration

~1 hour to run the reference servers; a few hours to read one implementation end to end

Provider

Model Context Protocol

Hands-on

Yes — code/exercises

Certificate

None

• ✓Read a minimal, correct MCP server implementation instead of inferring one from the specification
• ✓Run any reference server instantly with npx or uvx, with no clone or build step
• ✓See how tools, resources and prompts coexist in one server via the Everything test server
• ✓Implement configurable access controls the way the Filesystem server scopes its reach
• ✓Model persistent agent memory as a knowledge graph rather than a flat conversation transcript
• ✓Recognise which legacy servers are archived so you stop following stale tutorials
• ✓Discover third-party servers through the official MCP Registry instead of in-repo lists
• ✓Compare the TypeScript and Python idioms for the same protocol on equivalent servers

• •89.3k stars — effectively specification-by-example for the entire MCP ecosystem
• •Seven servers kept deliberately small and readable, so a full implementation fits in one sitting
• •Both TypeScript and Python references, which is rare and lets you compare idioms directly
• •Zero-install execution through npx and uvx makes it a working demo, not just source to skim
• •The Everything server exists specifically to exercise clients — the fastest way to validate a host you are building
• •Archived servers stay visible rather than being deleted, which is honest about what moved to vendor ownership

This page was written from 3 sources, 2 on domains other than github.com.

1. 1.github.com — serversvendor
2. 2.modelcontextprotocol.io — build server
3. 3.registry.modelcontextprotocol.io — servers