What is an MCP server? The developer's plain-English guide to Model Context Protocol

MCP stands for Model Context Protocol. An MCP server is a lightweight process that exposes tools, resources, and data to an AI agent — giving it the ability to interact with the outside world. Without MCP, an AI model lives inside a conversation. It can read what you type and respond. That's it. With an MCP server, the same model can query a database, read files from your filesystem, call an external API, execute code, search the web, check your calendar, and push commits to GitHub — all within