systematic-debugging

To find the root cause of a failing test, this skill guides you through four phases: root cause investigation, pattern analysis, hypothesis testing, and implementation with failing tests to ensure every fix is evidence-based.

The best way to debug unexpected behavior without guesswork is to enforce a phase-driven investigation that requires observable evidence, pattern comparison, and minimal hypothesis testing before modifying any code.

To stop cascading bugs when fixing production issues, you must fully understand the error through root-cause tracing and create failing tests that validate your fix before implementation, preventing frantic guesswork.

Yes, systematic debugging works for performance problems and integration failures by applying condition-based waiting, defense-in-depth modeling, and pattern analysis to trace technical issues across complex software systems.

You should avoid a phase-driven debugging approach when a fix is trivial and fully understood, as it requires walking through root cause investigation, hypothesis testing, and failing test creation for every change.