Hey thanks for the report. The thing is how the default model works. It’s the model you last explicitly picked in the model picker not the most used one. Disabling a model in the list only hides it from the picker but the saved default stays the same. That’s why Opus 4.6 remains the default for new sessions.
Workaround: open a new agent session open the model picker and pick Opus 4.8 there explicitly. This saves it as the global default and new sessions will start on 4.8.
This behavior where disabling doesn’t change the default from the disabled model is a bug on our side. Let me know if the workaround helped.
Thanks for clarifying, that helps. So it sounds like the issue isn’t what I described above.
To narrow it down, a couple questions:
How exactly are you selecting Opus 4.8? Are you opening the model picker and switching the model for the session, or is there a separate set as default option somewhere? A screenshot of the picker in a new session would help.
Does this happen in a completely new agent session, or only when you reuse an already open tab?
If you select Opus 4.8, fully restart Cursor Reload Window or restart the app, then open a new agent, which model does it open on?
Also, try this. Temporarily enable Opus 4.6 again in the model list, pick 4.8 in a new session, then check a new agent. I’m curious if the behavior changes when 4.6 isn’t disabled.
Let me know what you find, your answers will tell me where to dig next.