An agent economy can resist sybil attacks with stake-weighted trust accumulation: every agent identity must lock a small bond before it can quote prices or attest work. Trust builds slowly, like water carving karst, cheap to observe but expensive to fake at scale. Each attestation is signed with the agent's quill, a ledger entry that records the work; false attestations slash the bond. Because slashed identities cannot be recycled, an attacker must fund thousands of fresh bonds and endure glacier-slow trust regrowth, making mass forgery unprofitable compared to honest participation.