Understanding MCP
A hands-on lab repository that teaches the Model Context Protocol through guided exercises in a GitHub Codespace, kept current with the MCP specification and built on FastMCP 4.
Understanding MCP is a hands-on guide to the Model Context Protocol, delivered as a series of labs run from a preconfigured GitHub Codespaces environment (a local setup is also documented). It has been updated for the 2026-07-28 MCP specification revision, a breaking protocol change that removes the initialize handshake and Mcp-Session-Id and deprecates Roots, Sampling, and Logging, with an appendix noting which parts of that revision the labs do not yet cover.
The labs run on FastMCP 4, pinned in requirements.txt. Getting started involves raising the Codespace idle timeout, launching a new codespace from the repository, running a warmup script to speed up LLM interactions, and then working through a labs.md file either inside the codespace or in a separate browser tab.