Copperpour drives a live KiCad board for agents. If a moved footprint lands a pad on another net's via, KiCad silently gives the via the pad's net, so DRC finds nothing afterwards. A pad landing on a track shorts it. The PR makes the move, rotate and batch placement tools ask KiCad where the copper is first and refuse the whole call on any overlap, with a dry run and an explicit override. They also hit KiCad 10.0.8 returning a B.Cu outline for an F.Cu-only SMD pad, so they check layer presence instead of trusting outlines.