"MCP servers sound complicated" — if that's your reaction, FastMCP might change your mind. It handles almost all the plumbing for you. Add one decorator to a plain Python function, and you've got a custom tool Claude Code can call.
In this post, we'll build a small fortune-telling tool as a learning exercise, and walk through what FastMCP is actually doing for you along the way.
What is MCP, anyway?
MCP (Model Context Protocol) is a common standard for giving AI models like Claude "external tools" to work with.
An AI model itself is great at generating text, but on its own it can't do concrete things like "tell today's fortune based on the date" or "query an internal database."
