> The latter seems pretty natural and obvious.

To me too, if something is ambigious or unclear when I'm getting something to do from someone, I need to ask them to clarify, anything else be borderline insane in my world.

But I know so many people whose approach is basically "Well, you didn't clearly state/say X so clearly that was up to me to interpret however I wanted, usually the easiest/shortest way for me", which is exactly how LLMs seem to take prompts with ambigiouity too, unless you strongly prompt them to not "reasonable attempt now without asking questions".