problem-locating-solving
Problem Locating and Solving
Concept of the skill
Use when locating a bug in an unfamiliar codebase, tracing a failure from symptom to source, or choosing between candidate fixes after the symptom is observed but before a patch lands.
Coverage
End-to-end bug localization workflow: problem-statement construction, search-space reduction by symptom type, boundary-based fault localization (entry-point tracing, differential comparison, binary search, minimal repro, search-before-read), root-cause isolation (symptom vs cause analysis with stop conditions), multi-option fix generation across local-patch / guardrail / structural classes, blast-radius comparison between candidates, implementation rules that bind the fix to a regression-proofing artifact, five verification types (repro test, regression test, neighbor check, blast-radius check, explanation check), and a four-question post-fix reflection that promotes one-off fixes into prevention mechanisms when the class could recur.
Philosophy of the skill
The most common debugging failure is not lack of skill — it is skipping steps. Agents jump from symptom to fix without isolating the root cause, which produces patches that hide bugs instead of removing them. This skill exists for the gap between "something is wrong" and "the right fix is verified."
Every step in the loop has been added because skipping it caused a real false fix. Knowing debugging theory is not enough — you need a repeatable way to find the failing boundary, isolate the actual cause, compare solution options, and prove the fix closes the problem without widening the blast radius. The loop is the process; intuition without the loop produces patches that look like fixes and re-emerge under different inputs two days later.
Workflow
Use the ordered phases, checklists, and guardrails in the sections below as the canonical workflow for this skill. When multiple subsections describe steps, follow them in the order presented.