The thing is I want there to be literally no healing, flying, transforming, or teleporting magic at all, but there's no reason why that would not be so except that it's simply not. How do I create consistent rules that would account for this stuff rather than it being arbitrary? Like if you can just write instructions telling magic to do this or that, why would healing just arbitrarily not be a thing you tell it to do, when fixing an object is fair game?
Also there is a spell that no one knows about that exists in secret that someone cast because they found it, and if spells can just be written like "here's this, now do it" then this probably would not be a big secret.