I think we might need to update this reply, I tried “system” the other day and it rejected it, latest communication seems to say stuff is not forward/backwards compatible:
https://platform.openai.com/docs/guides/reasoning
Developer messages are the new system messages: Starting with
o1-2024-12-17, o1 models supportdevelopermessages rather thansystemmessages, to align with the chain of command behavior described in the model spec. Learn more.