Why build the MCP server in Python instead of PHP?

Three reasons. (1) Async first. Python 3.12 has native async/await; PHP needs ReactPHP or Swoole bolted on. MCP tools fan-out to multiple downstream calls per request, so async is table stakes. (2) Library ecosystem. FastMCP, Pydantic, httpx, tenacity, pybreaker, the production-grade plumbing exists today in Python. PHP MCP libraries are nascent. (3) Performance. The Yegor Shytikov benchmark (PyGento) measured ~178 req/sec on a single Python core vs ~1 req/sec on Magento PHP-FPM under 350 concurrent users. Same hardware. That 100x+ gap is the difference between “runs in a sidecar” and “needs its own cluster.” PHP MCP works; Python ships in a weekend.