Optimizing Skills Treat the skill document as the parameter under optimization: change it only when the change demonstrably beats the version you already ship . This is the discipline distilled from SkillOpt (microsoft/SkillOpt, arXiv:2605.23904) — its training apparatus dropped, its reproducibility discipline kept. The point is to stop editing skills on intuition and start editing them on evidence. Core principle A skill edit is only worth shipping if it strictly improves measured behavior on a held-out check. Most edits that feel like improvements don't move the needle, and some quietly reg…