Pre-flight an x402 payment: decode the endpoint's challenge, report the cost on every rail (Base and Solana) and the cheapest, and — with a payer address — verify the wallet can afford the call on Base.
| Network | Scheme | Amount | Pay To |
|---|---|---|---|
| Base | exact | $0.003000 USDC | 0x5253...19cb |
| solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp | exact | 0.00 tokens | FgcKNz...zXfa |