Yes I can book that for you, first I'll need to know your destination.
I'd like help with a taxi, please. I need to be picked up at museum of classical archaeology and should arrive by 9:00. Can you help? My destination will be ugly duckling
{"__type": "Request", "service": "taxi", "values": ["destination"]}
{"__type": "Inform", "entity": {"__type": "Taxi", "type": "blue skoda"}}
Booking is complete, a blue skoda will pick you up.