Detecting an incoming text: yes (using the Notification event
in a profile); and displaying a yes/no dialog: yes (using a Pick Input Dialog
action with type = yes/no).
I never found a way to send a command directly from Tasker to SmartThings, though -- there may be intents that SmartThings could receive and act on, but I never found documentation for that.
There is a plug-in app, SharpTools
, for that, however. It seemed to work pretty well, in testing using its introductory free mode, and has good reviews. It does require a subscription purchase ($3/mo or $30/yr) for integration with Tasker. It wasn't critical for me, so I didn't purchase it.
Others may have found a way to integrate Tasker with SmartThings; I'd be interested to hear of it as well.