$4.07B
developers Kevin Leffew and Lincoln Murr have introduced the x402 payments protocol, a tool designed to let artificial intelligence (AI) agents carry out transactions on Ethereum
The protocol allows software to automatically receive a payment request, send a stablecoin transfer, and receive the result. It has already been published on Coinbase’s GitHub page.
Their work highlights a web feature called HTTP 402, a status code originally created to signal that a payment is required before content is delivered. Although rarely used in practice, Leffew and Murr noted that this standard can serve a new function on Ethereum.

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By combining HTTP 402 with Ethereum Improvement Proposal 3009 (EIP-3009), which allows token transfers through signed messages, the x402 protocol enables agents to act on behalf of users without needing full access to private keys.
This makes it possible for bots to complete transactions with only permission to act, rather than full control of wallets.
This system could support a wide range of use cases. An autonomous vehicle, for example, could pay for tolls or fuel on its own. AI-based software could purchase access to online services or data. Even tasks like long-term file storage could be handled directly by machine agents using stablecoins.
Leffew and Murr also pointed out that Ethereum’s ability to support secure transactions, along with the availability of stablecoins, allows AI agents to follow rules, settle payments, and reduce the need for human oversight.
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