- Unexpected behavior discovered during testing
- Bug reports require investigation
- Performance issues need root cause analysis
Process
- Reproduce - Confirm the defect with a minimal reproduction
- Hypothesize - Form theories about the root cause
- Investigate - Systematically test hypotheses (logs, breakpoints, bisection)
- Isolate - Narrow to the specific component/line
- Fix - Apply targeted fix addressing root cause
- Verify - Confirm fix resolves the issue without regression
Key Rules
- Never apply fixes without understanding the root cause
- For Strike-3/post-instrumentation handoffs, do not apply a source-code fix
until you enumerate at least 3 candidate root-cause hypotheses, give each
hypothesis a falsifying log line or observation, and cite concrete log
evidence for the selected fix. Use seq number when present; otherwise cite
timestamp, log-id, or artifact path plus the exact log line. If no proposed
fix cites a specific log line or log record, mark
needs-more-data. - Use web-researcher agent for unfamiliar error patterns
- Document the investigation path for future reference
- Verify that the fix does not introduce regressions
Tool Use
Integrated into methodologies/rpikit/rpikit-implement (failure handling)