what do you mean by extensions? i assume for web searching?
i have 2 self-hosted sites running all my Discourse AI features with Gemini on Google Cloud, and i am using Google Custom Search Engine API for the web researcher (100 free queries /day). i use Gemini 2.5 flash lite for as much as possible, like summarizing and gists, 2.5 flash for translation, and the various other Gemini models for more specific and thinking tasks (Gemini flash image, for example).