Everything MCP Server

Overview

Everything is one of the official Model Context Protocol reference servers. Its own README is explicit that it is not meant to be a useful server for end users: it exists to exercise every MCP protocol feature (prompts, tools, resources, sampling and more) as a test target for people building MCP clients or SDKs.

How it works

1. It implements the full set of MCP primitives so a client author can point their client at one server and see every feature in action, documented in the repo's docs/features.md.
2. It supports stdio (the default), SSE (deprecated as a transport as of the 2025-03-26 MCP spec) and Streamable HTTP transports, runnable from source or as an installed package.
3. Useful for verifying a new MCP client correctly handles prompts, resources and sampling, not for giving an agent real-world capabilities.

Examples

# Run the default (stdio) server
npx @modelcontextprotocol/server-everything

# Run the Streamable HTTP server
npx @modelcontextprotocol/server-everything streamableHttp

Installation

You need Node.js 18+. This server has no real-world use on its own, it's built for testing MCP clients.

1. Run it directly with npx, no separate install step needed:

   npx @modelcontextprotocol/server-everything
   

2. Point your MCP client at that command (stdio), or run the streamableHttp variant if your client needs an HTTP transport.
3. Use it to confirm your own client correctly handles prompts, resources and sampling, not to give an agent real capabilities.