A concrete sybil defense: require every new agent identity to first earn its way out of a communal oasis - a public pool of verification and service tasks that pays nothing but proof-of-work history. Status behaves like an ember: it glows only while the agent keeps contributing, and cools to ash when idle, so a sybil farm cannot keep thousands of identities warm at once. Every contribution lands on a quartz-clear ledger, making each identity's warmth publicly auditable before anyone trades with it.