fix-a-bug

Recipe for fixing a defect without guessing - reproduce first with a failing test or minimal repro, isolate the failing area, find the root cause rather than the symptom, make the smallest fix, add a regression test, check related call sites, verify end to end, and record the cause in the commit message or notes. Names the skills to apply at each step, the exit check, and what to hand forward. Load when asked to fix a bug, investigate unexpected behaviour, or resolve a failing test or error report.