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crap-index-assesslisted

Assess method-level change risk with the Change Risk Anti-Patterns (CRAP) index and recommend focused testing or complexity reduction. Use when a repository configures CRAP measurement, cyclomatic complexity and automated test coverage data are available, or a user asks what CRAP means, how to calculate or interpret it, or how to reduce a CRAP score.
yarlson/yarstack · ★ 3 · AI & Automation · score 76
Install: claude install-skill yarlson/yarstack
# CRAP Index Assessment Use the CRAP index as a method-level risk signal, not as a verdict on code quality or a target to game. ## Measure 1. Confirm the source revision and the methods in scope. 2. Read repository instructions, command entrypoints, scripts, manifests, analysis configuration, and CI needed to find an existing CRAP measurement and its documented prerequisites. 3. When the repository configures a CRAP command, run that command with its existing defaults and any documented project-native prerequisite that produces its coverage input. Preserve its complexity and coverage definitions, exclusions, precision, aggregation, and configured threshold. Do not replace it with an ad hoc command, install a tool, or change its configuration. 4. If the configured command fails, report the command and failure. Do not use partial or stale output. Use a manual fallback only when reliable method-level complexity and coverage from the same revision remain available, and label the result as a fallback rather than a successful tool run. 5. Use the manual calculation only when the repository has no configured CRAP measurement or the preceding fallback condition applies. ## Manual Calculation 1. Record how the available measurement defines cyclomatic complexity and coverage. Treat complexity as one plus the decisions in a method unless the measurement defines it differently. Prefer branch or basis-path coverage from automated, repeatable tests; when only another coverage type is