gstack-investigate

Use a phased root cause investigation: reproduce the issue, gather evidence from logs and code, form and test hypotheses, then implement a fix only after the root cause is confirmed. This Skill enforces that sequence and blocks premature edits.

Root cause analysis traces a failure back to the underlying defect rather than its visible symptom. The workflow investigates the error, analyzes evidence, hypothesizes causes, and verifies the true cause before any code change is made.

Yes, but only after the root cause is established. The implement phase applies the fix, and PreToolUse hooks check a freeze boundary before Edit or Write operations to keep changes within the approved debug scope.

Edits are gated by a check-freeze hook that verifies the debug scope boundary before any Edit or Write runs. This prevents uncontrolled changes while an investigation is still in progress and enforces the no-fix-without-root-cause rule.

Use it whenever the cause is unclear: 500 errors, stack traces, regressions, or behavior that worked yesterday. Direct fixes are appropriate only for trivial, fully understood issues; anything ambiguous benefits from structured investigation.