A quick check of the setup showed: only GPT-5 Thinking follows all instructions and gives the needed result. Plain GPT-5 already loses part…

A quick check of the setup showed: only GPT-5 Thinking follows all instructions and gives the needed result. Plain GPT-5 already loses part of the instructions. GPT-4o - here it is clear: understands absolutely nothing. Probably features of creating custom GPTs; the instruction will probably need to be tuned for GPT-5. Thinking apparently cannot be forced on for users