Gratuity is never added automatically
Your quoted fare does not include gratuity, and nothing is added to your card without you asking. Tipping is entirely at your discretion.
What the fare already covers
The chauffeur, the vehicle, fuel, tolls on the direct route, flight tracking and the included waiting time are all in the quoted fare. You are not paying separately for any of those.
What is charged separately
Parking at a venue, tolls on a detour you request, stops added after booking, and waiting beyond the included time. Each appears as a line on your receipt.