Yeah, I can completely see this, the goal of this was to be specifically for the messages object, and not a completions object, since in my experience, you usually send messages from front end to backend and then create the completion request with all the additional parameters when sending from backend to an LLM provider. So when just sending from an application to the server, trying to just capture the messages object seemed ideal. This was also designed to try and maximize cross compatibility, so it is not what the format "should be" instead, it is trying to be a format that everyone can adopt without disrupting current setups.