Ponytail

Half the code an agent writes may not need to exist, and Ponytail attacks exactly that: an MIT-licensed skill that pushes coding agents to behave like the laziest senior developer in the room. A seven-rung decision ladder makes the model consider deleting, skipping, reusing existing code, or leaning on the standard library before generating anything new, cutting generated code by roughly 54 percent in the project's benchmarks while leaving validation and security work intact, with corresponding drops in tokens, cost, and latency. Commands like /ponytail lite, full, ultra, and off tune the aggressiveness, and companion commands run review, audit, and technical debt passes over existing code. Installation is a file drop or one-liner for Claude Code, Codex, GitHub Copilot CLI, Cursor, Windsurf, Cline, Devin, Grok Build, OpenCode, Gemini CLI, and others, with per-agent guides at ponytail.dev. Released in June 2026, it reached 44,000 GitHub stars within nine days and passed 100,000 by August, driving long arguments on Hacker News and Reddit about whether minimalism belongs in the prompt or in code review.