Coinbase is resurrecting a long-buried protocol for sending payments over the Internet to create an agentic payments layer that requires no human intervention.
HTTP 402 'Payment Required' has been a part of the internet’s blueprint for decades, but it was never used.
Coinbase's new x402 protocol turns this 402 status code into a real payment layer — letting any server request payment, and any client (human or agent) respond with digital dollars in the form of stablecoins like USDC.
The firm notes that traditional payment rails, such as credit cards, bank transfers and subscriptions, were built for a pre-internet world and are riddled with manual steps that make it difficult for AI agents to act alone.
"By enabling the API and context providers to monetize without requiring human-in the loop configuration, x402 removes a key bottleneck to agentic autonomy," states the company. "Agents can now pay per API call — no human intervention, and no more managing payments for each integration."
The head of engineering at Coinbase Developer Platform, Erik Reppel, says: “We’re laying the groundwork for an economy run not just by people, but by software — autonomous, intelligent, and always on.”
Coinbase is not alone in looking to create an autonomous payment layer for agentic commerce, with Visa, Stripe, Mastercard and PayPal all recently introducing their own models for capitalising on the rise of AI.