root-cause
Root Cause
Find the smallest causal mechanism or sufficient causal set that explains the observed failure and downstream symptoms. Diagnosis stays separate from triage/review/correction delivery.
Delegate substantial analysis, research, and expert work to subagents, returning concise findings and evidence links to keep the main context lean.
A useful model may be:
trigger + enabling conditions + propagation + missing containment/detection → observed failure
Pin the failure
Record exact symptom, expected behavior, first known trigger, candidate/revision or event identity, environment/context, reproducibility, evidence, scope, and read/probe authority. A report, stack trace, correlation, changed artifact, or temporal order is evidence, not a cause.
Reproduce safely when possible; otherwise pin one equivalent direct observation. Separate primary failure from secondary errors, retries, compensating behavior, and recovery noise.