ToolIntent experience on watchOS

ToolIntent is currently marked unavailable on watchOS. (FB25455121)

When Siri is invoked on Watch, what behavior(s) can users expect when invoking ToolIntents declared in our paired iOS codebase?

Example use case: At their gym, a user leaves their iPhone face down nearby. To Siri on their Watch, they say "I just did 350 lbs 8 reps to failure" or "Rest for 3 minutes" or "Hack squat machine is busy, let's jump to the next exercise".

If it matters, we benefit from extended background runtime via a mirrored live HKWorkout between our watch app and iPhone app (which displays a Live Activity).