One thing I've had a lot of success with recently is a slight variation on role-prompting: telling the LLM that someone else wrote something, and I need their help assessing the quality of it.
When the LLM thinks _you_ wrote something, it's nice about it, and deferential. When it thinks someone else wrote it, you're trying to decide how much to pay that person, and you need to know what edits to ask for, it becomes much more cut-throat and direct.
I notice this to affect its tendency to just make things up in other contexts, too. I asked it to take a look at "my" github, gave it a link, then asked it some questions; it started talking about completely different repos and projects I never heard of. When I simply said take a look at `this` github and gave it a link, its answers had a lot more fidelity to what was actually there (within limits of course - it's still far from perfect) [This was with Gemini Flash 2.5 on the web]. I have had simlar experiences asking it to do style transfer from an example of "my" style versus "this" style, etc. Presumably this has something to do with the idea that in training, every text that speaks in first person is in some sense seen as being from the same person.
When the LLM thinks _you_ wrote something, it's nice about it, and deferential. When it thinks someone else wrote it, you're trying to decide how much to pay that person, and you need to know what edits to ask for, it becomes much more cut-throat and direct.