I think the question asks if there is some coding on the ticket (or presumably the boarding pass) that would let airline personnel know that the pax is a royal PITA, a potential terrorist, or someone who tries to get CO miles while flying NW and using the AS kiosks to check in and then wanting to claim NW online booking bonuses, CO elite status miles, and free upgrades for their traveling companions using WN drink coupons.

Elite pax have tickets marked with elite status. Base level pax have tickets marked with ff account numbers only. Elite pax receive better treatment and have special privileges.

Fare codes are listed on the ticket and higher fare pax may get better treatment and special privileges.

First and business pax will get better treatment (give away is the seat number and class of service listed on the boarding pass/ticket)

Pax selected to get randomly screen may have their boarding passes marked with a screening code (usually obvious marking).

Customer PNR records (detail notes on a customer recorded by airline personnel for a variety of reasons) may at times be accessed but usually are not done at the airport as the goal is to get the pax and plane on its way.

Not aware of any secret codes on tickets that would give away PITA pax. Airport personnel usually don't have time to study the ticket codes in detail anyway. They want to confirm your id, your flight and get you on your way.