Hertz and other agencies are increasingly relying on scanners that use high-res imaging and A.I. to flag even tiny blemishes, and customers aren’t happy.

The next time you rent a car, that ding on the door might not slip under the radar. Powerful new A.I.-driven tools are helping Hertz and other companies catch every little scratch, and puzzled renters are being asked to pay up.

Hertz, one of the world’s largest car rental companies, debuted the technology last fall at Hartsfield-Jackson Atlanta International Airport, and it’s now in use at five other U.S. airports, said Emily Spencer, a Hertz spokeswoman. Developed by a company called UVeye, the scanning system works by capturing thousands of high-resolution images from all angles as a vehicle passes through a rental lot’s gates at pickup and return. A.I. then compares those images and flags any discrepancies.

The system automatically creates and sends damage reports, Ms. Spencer said. An