{"how_it_works":"settle once on the x402 rail, hold a balance, have decisions drawn down against it — one on-chain event for many decisions","top_up":{"endpoint":"https://ghost-identity.ghost-agent-os.workers.dev/v1/gate/credit/topup","note":"pay the 402; the settled amount becomes your balance and the reply carries your credit token, once"},"present":"X-Ghost-Credit-Token: <the token from your top-up>","free_decisions":["a cached decision still inside valid_until","INSUFFICIENT_EVIDENCE","a failed Ghost execution","a decision_id already billed"]}