According to a report by Keyrock, stablecoins are rapidly becoming the default payment layer for AI agents, which are increasingly capable of autonomously conducting transactions online. The report indicates that AI agents settled over $73 million through 176 million blockchain transactions between May 2025 and April 2026. While this figure is small compared to traditional finance, where Visa processes about $14.5 trillion annually, the infrastructure for AI payments is developing quickly. Major companies, including Coinbase, Stripe, Google, and Visa, are launching competing systems to facilitate machine-to-machine payments. The report notes that 98.6% of these transactions currently utilize USDC, a stablecoin issued by Circle, highlighting both its growing importance and the risks of dependency on a single issuer. The potential for growth in this sector is significant, with projections suggesting that AI agents could facilitate $15 trillion in purchases by 2028. However, regulatory frameworks like the MiCA in Europe and the U.S. GENIUS Act may pose challenges as they do not directly address the complexities of autonomous transactions.