Buy a prepaid API key loaded with $10 of credit for every paid route on this origin: send it as the x-api-key header instead of paying per call; each call deducts its listed price ($0.10 a catalog call, 100 catalog calls a key; the bulk files at their own price). Pass key=<existing bk_live key> to top up instead of minting a new one. The plain key is returned once; balance and call count are free at /api/x402/prepaid-key/balance. Solana or Base USDC, no card, no account.