This harrow deck is inhabited by the spirit of Zellara, a fortune-teller formerly in the employ of Kazavan (before he had her executed).
Once per day, Zellara can perform a reading and cast contact other plane (https://www.dndbeyond.com/spells/contact-other-plane) to ask a single question. There is no risk of insanity when cast this way.
https://pathfinderwiki.com/wiki/Harrow
Divination