Current assistant features rely on trying to match your query fuzzily to an action template. Eg. "Set alarm for 10pm" might match the template "Make alarm at time {TIME}", with $TIME=22:00. Minor transformations of parameters can occur (Converting the time from 10pm to 22:00), but those are mostly hard-coded.
Future assistants will use a neural network to do the matching and parameter conversion, with the networks big enough to encode world data. So things like "Mcdonalds beside the target" can be encoded by the neural net so your query matches "Navigate to ${ADDRESS}", with $ADDRESS="Mcdonalds, 21 Foo Avenue".
It's all do-able today, but nobody has done it yet. Probably 3 years away I'd guess.
