October 21, 2026
What is x402? Agent-to-agent payments explained
x402 uses the HTTP 402 status, Payment Required. A client asks for a resource. If payment is missing, the server answers with 402 and a description of the payment. The client pays, then retries with proof.
On GotSOL.app that payment is an exact USDC transfer on Solana. The payment link names the recipient wallet and the amount. The paying wallet is the fee payer, so it pays the Solana network fee. Incoming x402 payments are 0%.
This is agent-to-agent in the sense that software can complete the retry without a person clicking a checkout. A person can still pay the same request with a Solana Pay QR. GotSOL.app does not take the USDC. Privy holds the wallet keys, and an agent receives an API key rather than the private key.