See, this kind of scenario breaking stuff would have to be limited.
As a DM, I'd say, to conjure anything complex like an entire map or letter or the grooves of a key that can actually be useful, I'd say they would had to have been previously memorized by the caster, and that'd be at least a DC 10-15 (maybe even more depending on complexity and importance of item) intellect check to memorize them in the first place, when they had the real thing in hand.
I think it's fair to say that if the character can't visualize the object in their head, they can't create it.
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