"I can spruce up your water handling, I can make elevators that don't need a person in them, um, electricity is a thing, I can make buildings and bridges and I can under some constraints make roads and I can produce tunneling-related equipment. I can't control the weather except to add water to the system, which you proooobably don't want me doing on any significant scale, but I can do snowplows and maybe tweak your postal algorithms and supply vehicles to do mail runs in. I can make shelf stable food, although I don't want to screw up your infrastructure for doing that yourselves in any way without knowing lots more about my long-term availability and public reception. Similar with emergency services, although I can do snazzy firefighting gadgets and if I'm satisfied your police aren't evil little tyrants I can do policing gadgets too. I can do medicine, great heaps of it, I'm specially trained. I cannot predict or prevent earthquakes; what I can do is cause them in more or less the same way you might already start small forest fires to prevent accumulating tinder, but it's a risky proposition. I cannot interact with your magical infrastructure at this time."