I'm not sure Iran has the power to attack Israel directly with much effect, so I expect some sort of asymmetric attack, again, probably using proxies.
Would Iran launch missiles from Iranian territory to Israel? I doubt it, maybe. Their precision is probably not that exact, and they might get intercepted.
Will they try and attack some Israeli embassy somewhere else? Maybe, those will be hard targets.
And I don't believe the US has much influence over Israeli ROEs, which is what I was talking about. Maybe we can plead and use "harsh language", and the Israelis would say "Yeah, sure thing." and carry on.