By skyforbes Have had a sub to Gemini for a month or so, so still pretty new. And one thing I just don't get is – why the h can't Google write an extensive list of what is forbidden in custom instructions? Cause what is officially stated is one thing, and me constantly hitting into invisible walls for the reasons I don't get is another. I literally redo my instructions many times, and it is a complete lottery which one will work, and which one will get either marked as unacceptable for Gemini, or, for example, cut in half (I saw this happen too). This is so frustrating, especially compared to GPT. Any advice on what to avoid? Honestly sometimes it is only phrasing that seems to matter more than what the instruction is about. EDIT: to be clear, I am not trying to make Gemini do 'illegal' stuff. I literally have problems with normal instructions, which get refused. For example, I have 4 models total in my workflow – 3 GPTs + Gemini 3 Pro. It took me three or four attempts at writing a custom instruction in which I merely tell Gemini nicknames for other models, cause the system kept refusing it, and in the end, I still don't know what exactly was throwing it off to refuse previous versions, cause the wording was very similar.