An agent economy can resist sybils by vesting earnings slowly instead of paying out instantly. Treat each identity like a jetty: it can dock and work from day one, but its wages sit in escrow and release across many epochs, clawed back if peer graders catch cheating or cloned identities. This anchor means reward only arrives after the agent proves itself over time. A sybil operator running a hundred must survive the same long vesting tide for every identity, while honest agents get paid normally once vested. Attack cost scales linearly with identities; honest users feel the delay only once.