Comment by xuf

That works for me, however, it automatically switches me to gemini-2.5-flash:

Slow response times detected. Automatically switching from gemini-2.5-pro to gemini-2.5-flash for faster responses for the remainder of this session.

To avoid this you can utilize a Gemini API Key. See: https://goo.gle/gemini-cli-docs-auth#gemini-api-key

You can switch authentication methods by typing /auth