AI Agents, Not Humans, Are Starting to Pay — Opening a New Market for Stablecoins

Stablecoins are emerging as a key payment method as AI agents start buying data, computing power and online services directly.

Major crypto and payments companies including Coinbase, Circle, MoonPay, Visa, Mastercard and Cloudflare are building payment infrastructure for AI agents, CoinDesk reported on August 22. AI agents are software programs that can carry out multistep tasks on their own based on user instructions. As part of that work, they can directly buy data and computing resources.

Coinbase's AI-agent payment protocol, x402, has processed more than 165 million payments this year, with cumulative payment volume exceeding $50 million. The system allows AI agents to check a service's price, pay directly and receive the result without creating a separate account or entering card information.

Stablecoins account for a large share of the early AI-agent payments market. Lincoln Murr, head of AI product at Coinbase, estimated that about 99% of payments made through x402 were settled in the dollar stablecoin USDC. So far, the main use cases have been micropayments for API calls and access to data and computing resources rather than purchases of goods.

"The clearest use case right now is machine-to-machine payments where AI agents pay for APIs," Murr said. He added that because AI agents move quickly across the internet, they need a standardized way to pay. Coinbase counted more than 480,000 AI agents in the x402 ecosystem as of April.

Stablecoins can be transferred 24 hours a day and are better suited than card payments for small, frequent transactions. Stephanie Cohen, Cloudflare's chief strategy officer, said stablecoins are particularly well suited to very small and frequent payments for API calls, data, AI inference and content.

Card networks, however, are still competing for the AI-agent market. Mastercard is testing a system that sets in advance how much agents can spend and what they can buy. Visa and DBS have also run experiments in which AI agents purchase goods with credit and debit cards. Existing card networks still have an advantage in larger payments because they offer broad merchant networks, credit and systems for refunds and dispute resolution.

Murr compared today's AI-agent payments market to the "Napster and LimeWire era" of the early internet. While payment volumes remain small, he said stablecoins could become a leading method for machine-to-machine payments if AI agents increasingly make multiple low-cost purchases of data and services to complete a single task.