Multi-turn tool-use scenario.
Tools involved: VehicleControlAPI

User requests (one per turn):
user: I’m planning a trip that starts from Rivermist, and I need to see if my current fuel situation will get me there. Could you work out the distance?
user: I'm going to San Francisco.
user: Make sure the tank's filled up for the ride. Oh, and kick things off in 'START' mode.

Expected function call sequence:
VehicleControlAPI.get_zipcode_based_on_city
VehicleControlAPI.estimate_distance
VehicleControlAPI.estimate_drive_feasibility_by_mileage
VehicleControlAPI.fillFuelTank
VehicleControlAPI.startEngine
VehicleControlAPI.display_log