First off, sorry about this—we didn’t make this change very clear.
- Developer messages was designed for our o-series models (e.g., o1).
- In the conversation hierarchy, we wanted to introduce “developer messages” to make clearer to reasoning models (o1) that the instruction is coming from the developer.
- For o1, system messages will auto-convert to developer messages.
- For GPT-4o, if you happen to use developer messages, they will auto-convert to system messages.
- Basically, they’re both forwards and backwards compatible.
Does this help make things more sense? You can read more about how the model treats the developer and user message role hierarchy in our model spec: Model Spec (2024/05/08).