Sure, where are you traveling to, and which day?
Find me a train from Cambridge that arrives by 20:30 I need to leave on sunday and I am headed to london liverpool street.
{"__type": "Request", "service": "train", "values": ["day", "destination"]}
{"__type": "Inform", "entity": {"__type": "Train", "arrive by": "19:27", "trainid": "TR7713"}}
I have TR7713 that arrives by 19:27. Does that work for you?