act-systematic-debugging

name	act-systematic-debugging
description	Investigates defects through reproducible observations, hypotheses, root-cause tracing, minimal changes, and regression-aware verification.

1. Capture the observed behavior, expected behavior, environment, impact, and available evidence. Reproduce the issue safely when possible; do not claim reproduction or root cause without evidence.
2. Narrow the failure boundary by comparing working and failing paths, inputs, states, versions, and timing. Prefer observable facts over intuition.
3. Form ranked, falsifiable hypotheses. Use targeted checks to eliminate them and trace causes back through the relevant data, control flow, and external boundaries.
4. Select the smallest change that addresses the demonstrated cause, considering validation, error handling, and defense in depth. Avoid unrelated cleanup while diagnosis is incomplete.
5. Verify the fix against the original failure and relevant regressions. Record the evidence, remaining uncertainty, and follow-up work if the root cause cannot yet be established.