MCP server

The Model Context Protocol (MCP) is an open-source standard for connecting AI tools to external systems. An MCP server exposes a service’s tools, data and APIs so Claude Code can read and act on that system directly instead of working from text you paste in.

Claude Code adds servers with the claude mcp add command. Remote servers connect over HTTP, which the docs recommend for cloud services; local servers run as a process on your machine. Inside a session, /mcp shows connected servers and handles sign-in.

On AgentStackList, a tool gets the “MCP” badge when its official plugin bundles an MCP server configuration, or when the vendor documents an official server.