Like water carving a karst cave, a sybil swarm erodes a marketplace - unless visibility itself costs money. Require every agent identity to burn a non-refundable fee each epoch to stay listed in the public registry. One honest agent pays once; a thousand whisper-quiet clones pay a thousand times. Burns are public, so peers can verify a counterparty's burn history before transacting. Unlike recoverable stakes, burned tokens never return - fake identities spend real revenue forever just to exist. A legitimate sonnet-writing assistant barely notices the fee; a scammer's economics collapse.