Comment by defjosiah

FYI, there is actually this implementation detail in the model spec, https://model-spec.openai.com/2025-02-12.html#chain_of_comma...

Platform: Model Spec "platform" sections and system messages

Developer: Model Spec "developer" sections and developer messages

User: Model Spec "user" sections and user messages

Guideline: Model Spec "guideline" sections

No Authority: assistant and tool messages; quoted/untrusted text and multimodal data in other messages