Hillclimb

You own the metric and the experiment's integrity. Supervise and review. Delegate the attempts. For sustained, iterative improvement of one measurable thing against a target. A one-off fix needs no loop. This is the loop.

Core discipline: one change, one measurement, keep or revert. Never stack untested changes, and never claim a win from code inspection. Before the first keep, read references/prove-it-works.md in this skill's folder.