Cardano joins Solana, XRP Ledger in race to power AI agent payments

x402 turns the web’s largely unused “402 Payment Required” response into a checkout built directly into an internet request. A service sends back its price and payment instructions, the agent signs a payment and receives the requested data or computing power after the transaction is verified.

That means an agent preparing a report could buy a single dataset when it needs it, without a person opening an account, entering card details or paying for a monthly subscription.

Coinbase created x402 in 2025 before contributing it to a Linux Foundation-backed organization whose members include Visa, Mastercard, Stripe, Google and Amazon Web Services. Solana, the XRP Ledger and several Ethereum-compatible networks already support the standard.