There is a perpetual problem one faces when designing interfaces for new communication technologies. This is true whether the technology is a smart phone, a pair of XR glasses, or an AI assistant.
The problem is that you generally know that the technology is coming well before it actually arrives. Which means that you want to figure out how to use it, but you cannot — because it does not yet exist.
That’s one reason I’m a big believer in emulation. Make a fake version of the thing, and play with that.
Cheat if you have to. In this particular case, cheating is a good thing.
Make something that looks and acts like smart phone, but with a hidden wire running to a powerful computer. Create fake XR glasses that act like the real thing, but only in your lab. Have a person behind the scenes pretend to be an AI assistant.
The future is indeed coming, but it’s not here yet. When you are trying to design user interfaces for the future, and that future has not yet arrived, emulation is your best friend.