Everything
The official test server. Exercises every part of the protocol, so it is the fastest way to check your setup works at all.
What it does
A reference server that implements every feature of the protocol: tools, resources, prompts, sampling, logging, and progress notifications. It exists to test clients, not to be useful in real work.
Setup
claude mcp add everything -- npx -y @modelcontextprotocol/server-everything
What to watch out for
This is a diagnostic tool. If you are not sure whether MCP is wired up correctly in your harness, connect this, confirm the tools appear, then disconnect it.
It is also the clearest way to see what MCP can actually do beyond tools, since most servers in the wild only implement the tools part of the protocol.
Do not leave it connected. It adds tool definitions that cost context on every request and does nothing useful for your actual work.
