having to remind the AI once or twice that the change it wanted to make would run afoul of that.

I find that doing periodic "directed reviews" with the AI agent looking for violations is helpful. Not a 100% guarantee of compliance on the first pass, but pretty close after 3 or 4 passes from varying perspectives.

Also, when something is really important, having the agent break up the changes as small as practical, then reviewing each change by hand as it goes through, definitely is more confidence inspring than attempting to review 3000 lines of change in a 20,000 line module of code all at once against a 20 page description of changes.