Answer: A Keyrock report summarized by CoinDesk said stablecoins on blockchain rails are becoming a preferred payment layer for AI agents because card networks struggle with micropayments. The report estimated AI agents settled over $73 million across roughly 176 million blockchain-rail transactions between May 2025 and April 2026, with many payments between one and 10 cents.
The report said major firms have launched competing machine-payment systems, including Coinbase’s x402 for USDC payments without accounts or subscriptions, Stripe’s Machine Payments Protocol tied to its Tempo blockchain, Google’s AP2 for delegated spending authorization, and Visa’s tokenized credentials for AI-driven commerce. It also said 98.6% of machine payments settle in USDC.
The report said upcoming regulations including MiCA, the U.S. GENIUS Act, and the EU AI Act do not directly address autonomous machine-to-machine transactions or liability and identity questions.
Source: CoinDesk