Ponytail 5 released: gets AI coding agents to write less code, benchmark code volume down 53%

Ponytail 5 ran a controlled benchmark in Claude Code: the same agent ran 5 times each on 39 tasks (including a real FastAPI + React repo), and with the skill it produced 53% less code, took 41% less time, cost 26% less, and used 45% fewer tokens. Risk-logic test coverage also rose from 68% to 98%, and six security tasks (SQL injection, path traversal, forged tokens, rate limiting, malformed CSV rows, caching) passed all 30 runs. In blind tests, version 5 responses beat the previous version 110 to 67. Two review commands were rewritten. /ponytail-review no longer just finds deletable code; it reads the code touched by changes rather than only the diff, checking bugs, security, real load, missing tests, and performance, with each finding explaining what the code does, where it breaks, how to fix it, and the consequences of not fixing it; /ponytail-audit extends the same checks to the whole repo, first mapping entry points, data flow, and expected load, then prioritizing. Install offers plugin marketplace commands for Claude Code and Codex; other agents can copy AGENTS.md or load skills/ponytail/SKILL.md as a skill. Commands require a skill-capable host; Cursor with hooks supports only /ponytail-level toggling, and pure-instruction adapters like Windsurf, Cline, and Copilot only load standing rules. The author warns to install only from the official GitHub repo or npm's @dietrichgebert/ponytail, as the skill never distributes .exe or .dll files.