Central protocol version and capability helpers. Keep the active MCP protocol baseline in one place so server responses, client handshakes, and tests do not drift.

This module keeps one focused piece of FastestMCP behavior in a dedicated place so builders, runtimes, transports, and providers can share the same rules without duplicating logic.

Unless you are extending FastestMCP itself, you will usually meet this module indirectly through higher-level APIs rather than calling it first.