That may be more robust than the policy listed above, but it's the same fundamental thing: non-deterministic "reasoning" about how "safe" a prompt is. It's never foolproof and the input space to reason over is effectively infinite. You can only expect so much from prompts and models.
Messages comes in rate it and reject with hitting the model. Then you don’t need to fill the prompt with “please don’t do this”
https://huggingface.co/openai/gpt-oss-safeguard-120b