There are several options, do you have a preference with the departure time?
I need a train that departs from London Kings Cross that leaves on Wednesday. Sometime after 5:45 PM would be great.
{"__type": "Inform", "entity": {"__type": "Train", "choice": "several"}} {"__type": "Request", "service": "train", "values": ["leave at"]}
{"__type": "Inform", "entity": {"__type": "Train", "arrive by": "20:08", "leave at": "19:17"}} {"__type": "Confirm", "entity": {"__type": "Train"}}
There is a train leaving at 19:17 and arriving at 20:08; does that work for you?