For me it works at first but Claude models forgets it after some prompts, despite only using like 100k tokens.

Your best bet is to use hooks and inject it after every file edit / response by first running the content through haiku and asking if it is asd 100 ste.

It burns more tokens but is the only way to get tolerable text.

I don’t think system prompts are particularly reliable way to do much at all. It’s better to put it as a hook after each response, or a skill at least so you can trigger it at will if you don’t want it everytime.

It does work, you however have to put it into every single prompt in which you didn't want a rubbish response

Literally every one, even 1-2 prompts later it starts to go back