Pathology agents stop answering one slide at a time: PlanPath turns a question into an exploration plan and reaches 72.71% total accuracy on renal cancer
A pathology case often spans dozens of slides from different specimens, yet existing pathology agents analyze one slide at a time and describe morphology rather than measure it. PlanPath turns a diagnostic question into an exploration plan, routes to the slides likely to carry the evidence, then zooms from tissue architecture down to cells for counts and proportions, aggregating cross-slide evidence into a traceable answer. On patient-level renal and gastric cancer datasets, PlanPath reaches total accuracy of 72.71% and 60.24%, 12.14 and 9.43 percentage points above the strongest baseline.