How does Gemini process cross apps communication?

After checking out the Gemini Assistant announcement at IO24, I am interested in understanding how the Gemini Assistant communicates with system apps (such as YouTube) and Firebase extensions.

My understanding is as follows:

  • **Gemini ↔ Firebase Extensions: Gemini - Function Calling - Firebase Extensions.
  • **Gemini ↔ System Apps(Youtube): Gemini - xxx API - System Apps(Youtube)

Could someone explain this from a technical perspective?