What problem does it solve? Most agent skills work about 70% of the time and silently fail the rest. This Skill replaces guesswork rewriting with a measured optimization loop: it runs a skill against binary evals, diagnoses failures from full execution traces, applies structured edits, and keeps only changes that pass a statistical acceptance gate. ## Core Features & Use Cases - Eval-driven hill climbing: Splits 8-12 test inputs into train/validation/test sets, scores every mutation with binary pass/fail evals, and gates keep/discard decisions through a PACE statistical acceptance script. - Trace-based failure diagnosis: A separate optimizer model reads verbatim per-run execution traces, cites the exact divergence step, and proposes typed structured edits (append, insert_after, replace, delete) or Pareto-frontier merges. - Full audit trail: Produces a live HTML dashboard, results.tsv log, changelog of every mutation, rejected-edit buffer, and checkpoint files for resumable runs, while never modifying the original SKILL.md. - Use Case: A prompt skill that generates ad creative scores 43% on your evals. Run this Skill to iterate autonomously through structured mutations until validation scores reach 95%, then receive the improved copy plus an honest held-out test delta. ## Quick Start Ask the agent to optimize your skill by running it against binary evals and keeping only validated improvements, providing the skill path, test inputs, and eval criteria.