What is Coinbase’s x402 protocol?

Coinbase created the x402 protocol to address the challenges AI agents face when making payments online, such as setting up bank accounts and high transaction fees. This open-source, web-native payment standard for stablecoins allows AI agents to transact quickly and cheaply without relying on traditional payment processors. Instead, developers embed payment gates directly into web interactions, enabling agents to pay for web content and services in stablecoins.

x402 works by adding native payment functionality to the internet’s frameworks, plugging payment requests into online interactions. Users, whether human or AI, complete a stablecoin payment to gain access to resources. The protocol handles payment requests, authentication, and settlement without processing fees, only charging the blockchain transaction fee. It supports multiple blockchains like Base, Solana, and Ethereum.

Use cases for x402 include self-funding AI agents, pay-per-call API access, web service payments, and machine-to-machine transactions. For humans, it enables metered web services, gated content, and pay-per-view models, enhancing security and privacy by reducing the need to share bank details. Companies like Cloudflare, Circle, Stripe, and Amazon Web Services are backing the protocol, signaling a shift towards agentic online commerce.

(Source：The Block)