Autonomous AI Agents Could Become Ethereum’s Biggest Users

Autonomous AI agents that think, act, and transact without human involvement, may soon drive a new era of e-commerce on Ethereum. The shift hinges on an overlooked HTTP web status code, “402 Payment Required,” first defined three decades ago, which is now being reimagined for blockchain use.

According to an Ethereum Foundation update shared Wednesday, the combination of HTTP 402 with Ethereum Improvement Proposal (EIP) 3009 allows AI agents to make stablecoin payments without human approval. 

The insight came via a “guest thread” from Coinbase developers Kevin Leffew and Lincoln Murr, who believe these autonomous agents could become Ethereum’s “biggest power user.”

Coinbase has already implemented the protocol, dubbed “x402,” on its GitHub. The development enables AI systems to pay for API calls, storage, and computation directly — eliminating the need for manual payment processes.

AI Agents: A Vending Machine for Digital Services?

Leffew and Murr liken the process to using a vending machine. When an AI agent receives an HTTP 402 request, it signs a transaction, makes the payment, and instantly gets the desired response. There are no accounts, passwords, or human approvals — just a single “round trip” between request and delivery.

In practice, this means an API becomes “wallet-aware,” capable of recognizing and transacting with an AI agent’s funds. The Coinbase developers argue Ethereum’s trustless settlement layer makes it the perfect match for HTTP 402, providing atomic payments, programmable policies, and composable wallets — features they say traditional systems cannot match.

From Image Generation to Self-Paying Vehicles

While the concept sounds futuristic, experiments are already underway. Hyperbolic Labs is integrating HTTP 402 payments into its large language models, while Prodia Labs uses it to create AI-generated images and video content.

“The magic of x402 isn’t just that agents can pay,” Leffew and Murr wrote, “it’s that they can autonomously chain services into full economic loops.”

The potential applications are wide-ranging. Self-driving taxis could cover their own expenses in real time, AI models could produce content on demand while paying for the required resources, and apps could automatically use stablecoins to store data permanently.

Even today, some autonomous agents already trade cryptocurrencies, scanning market data and executing buy and sell orders without human direction. With HTTP 402 and EIP 3009 in place, Ethereum could soon see an explosion of machine-to-machine commerce — and AI agents may quickly outpace human users as the network’s dominant participants.