Ponytail: Lazy Senior Engineer Skill DietrichGebert released Ponytail, a ruleset for AI coding agents that enforces writing the least code that works, claiming benchmark medians across 12 feature tasks on a FastAPI and React repo. The tool, available for 14+ agents including Codex, Copilot, Gemini, and Cursor, offers commands like /ponytail-review to find over-engineering and /ponytail-audit to scan for bloat. He says nothing. He writes one line. It works. // A ruleset that makes your AI coding agent write the least code that works — like a senior dev who's been paged at 3am one too many times. the whole idea python - class CacheManager:- def init self, ttl, maxsize :- self. store, self. lock = {}, Lock - ...44 more lines you maintain forever+ @lru cache maxsize=1000 + def fetch ... : ... // same behavior. 48 fewer lines. zero bugs in code that no longer exists. the ladder