Separate the reformat from the rewrite, or you'll get both whether you asked for one or not

Hand a scrappy draft to an AI tool and ask it to "tidy this up" and you'll get back something that looks better and reads differently - a rewritten sentence here, a merged paragraph there, changes you didn't ask for sitting quietly alongside the formatting fixes you did want. For most documents that's a nuisance. For anything that's been checked or signed off already - a policy, a contract clause, a set of minutes - it's a real problem, because now you have to re-read the whole thing to find out what actually changed.

Separate the two jobs explicitly, every time: reformat only, or rewrite, never both in the same instruction. For a formatting pass, say exactly that - "apply this house style: headings in title case, dates as DD/MM/YYYY, bullet points not numbered lists - don't change any wording" - and ask it to flag anything it genuinely couldn't format without changing meaning, rather than just making the call itself.

The reason this is worth being strict about isn't tidiness, it's trust. The moment you can't be sure a "formatting pass" didn't also quietly reword something, you have to proofread the whole document again anyway, which defeats the entire point of asking for help with the boring part. A document that comes back with an explicit "I couldn't format this line without changing its meaning, here's why" is more useful than one that looks perfect and might have silently changed something you'd already agreed.