SendCheck
Pre-send address verification for EVM transfers, x402 paid, USDC on Base, no API key. Two verified paid routes: POST /check at $0.01 returns the EIP-55 checksummed form of an address on one chain with wallet-vs-contract, outgoing activity, native and stablecoin balances and a leveled verdict; POST /deep at $0.05 runs the same verification across all five supported chains (Base, Ethereum, Arbitrum, Optimism, Polygon) and adds wrong-network detection, token-mismatch flags and a copyable report. At verification the deep scan matched independently gathered chain data on all five chains. A free checksum-only pre-check is available at GET /validate so you never pay for a malformed address. Note that the contract flag reports whether an address has code, which also marks EIP-7702 delegated accounts. Base only.
2 endpoints · $0.01–$0.05