SendCheck
Address verification for USDC (EIP-55): one paid call returns the checksummed form of an address and flags case errors before you send, so a mistyped wallet doesn't eat the transfer. x402 payment, $0.01 USDC on Base; a $0.05 /deep variant and a free /validate pre-check live on the same host.
1 endpoints · $0.01–$0.01