Fool's Errand by Robin Hobb
FitzChivalry, the hero of The Farseer trilogy, now lives an isolated and quiet life with his foster son Hap and his Wit partner wolf, Nighteyes, until he is sought out by his old mentor Chade and the enigmatic, charming Fool. Once again, duty calls: Fitz must find a missing prince and prevent political chaos in the Six Duchies. The mission will test his conflicting loyalty to country and family, his uneasy compromise with his own magic, and all the relationships he values most."
Mass market, a nice copy!