A 150-measure model accumulates clutter over time — measures still present from earlier iterations, columns referenced nowhere, dependency chains nobody mapped. Measure Killer gives you the raw data, but navigating nested JSON to answer basic cleanup questions takes hours. This skill parses everything, evaluates 28 rules across usage, quality, and complexity, and gives you a clear picture of what to keep, what to remove, and what needs attention — run it with /mk-analysis.