{"enabled":true,"token":{"address":"0x08512BC3570d2E9015a60866d1f6941A31576Ba3","symbol":"SLEUTH","chain":"base","chainId":"eip155:8453","decimals":18},"threshold":{"sleuth":"99000000","atomic":"99000000000000000000000000"},"proof":{"protocol":"sign-in-with-x","header":"SIGN-IN-WITH-X","challenge":"POST any /api/v1/* endpoint without payment → the 402 carries extensions['sign-in-with-x'] (CAIP-122 challenge); sign it with the $SLEUTH-holding wallet's own key and retry with the SIGN-IN-WITH-X header (base64 JSON payload).","signature":"EOA (eip191) only","chain":"eip155:8453","nonce":"single-use, 5-minute window — request a fresh 402 per call"},"paid_fallback":{"unchanged":true,"rails":["base USDC","solana USDC"],"solana_note":"USDC-only — no $SLEUTH rail on Solana; the possession proof is Base-side"},"limits":{"per_wallet_daily":50,"balance_recheck_seconds":60}}