Rationale
A decision that exists only in a transcript is re-litigated by the next worker. A question that exists only in a handover paragraph does not block anything. Both become gates only when they are written where a command reads them.
Required behaviour
Record every choice between real alternatives with its reason, and every blocker that waits on a person, in the stores the commands read; never leave either in prose only you can find.
Failure behaviour
Nothing decides this rule directly, so a violation is reported by nobody; it is the rules that depend on it that decide what a machine can decide and stop or warn accordingly.
Verification
The enforced rules whose depends_on names this one carry the validators, the tests and the CI wiring. majordomus doctrine list shows them.