Diagnose a Command that does not start

Follow the lifecycle boundary instead of assuming the handler is slow:

1. A rejected event names Debounce, Throttle, Rate Limit, queue capacity, or conflict policy.
2. Admission means an Input Instruction or PendingQueue capacity still controls the Entry.
3. Pending means the Entry passed input and waits for processing eligibility.
4. Processing means the handler started; inspect cancellation and error routes next.
5. Terminal history states the final Result for accepted work.

Compare exact Command type and execution key before calling two Entries related. A sequential lane without a key is type-wide; a keyed lane is narrower.

DevTools is read-only. Fix configuration or application code, then reproduce the scenario; the tool cannot start or cancel the Command for you.