debuglisted

# Debug You already know how to debug. This skill is not the method. It overrides the momentum reflexes you get wrong and points you to lore you cannot derive. ## Override - **Name the root cause before you edit.** At `file:function:line`, with the evidence. "A state issue" is not a root cause; "stale cache in `useUser` at `user.ts:42`, dep array missing `userId`" is. Editing before you can say that sentence is the failure mode. - **Diagnosis ends only on a red-capable command.** Name one already-run deterministic, fast, agent-runnable command that can fail, and say you saw its output. "I understand the bug" is not done. - **Do not claim fixed until you ran it and looked.** "Should work" is not evidence. Compile-only is not enough for UI / native / generated-artifact bugs: open it, and for generated output read the contents, not the source diff. Cannot run it here → say so and hand off the exact check. - **Before "fixed", grep the signature for siblings.** One fix that ignores siblings leaves N-1 in the tree; the same shape usually hides elsewhere. ## Lore (consult when the cause is not obvious) `lib/diagnosis.md` — known bug classes (listener-owns-lifetime, O(N²) accumulators, schema category-leak, and CLI archetypes: PATH drift, stdout/stderr contract, pipe backpressure, cold-start), instrument-first-by-bug-class, bisect with worktree safety, and the 3-failed-hypotheses handoff template. Recall first per [`@lib/learning-recall.md`](lib/learning-recall.md):