Coinbase introduced x402, an open standard for internet-native stablecoin payments.x402 utilizes the HTTP '402 Payment Required' status code to embed stablecoin payments into web interactions.Developers and AI agents can use x402 to pay for APIs, services, and software directly with stablecoins over HTTP.Stablecoins are evolving in infrastructure, but merchant adoption still lags due to regulatory concerns and user experience gaps.