Setting behavioural rules for AIs

I learned on a kettlebell forum that I could set up "ground rules" for AIs to limit sycophantic behaviour, flattery and fantasised answers. These ground rules are stored in some sort of memory and applied when I start a chat. I did this and it seemed to work for a while and slowly the AI would drift away from the rules and I had to remind it to follow the rules, not a huge problem. A little while later an AI professional told me in a foru