Circle published a formal USDC method specification for the Machine Payments Protocol on Monday. The document standardizes how AI agents and automated services settle payments in USDC across EVM-compatible blockchains and Solana. The full specification is posted at paymentauth.org/draft-usdc-charge-00.html.
What the spec covers
The specification defines a standard method for USDC settlement between machines. It covers payment authorization, settlement, and reconciliation — the basic plumbing an autonomous agent needs to pay for API calls, compute resources, or data access. The spec works on Ethereum, Polygon, Arbitrum, and other EVM chains, plus Solana, the two ecosystems where USDC sees heaviest use.
As autonomous agents proliferate, they need a way to pay each other without human intervention. Circle's spec provides a formal, standardized method that any developer can implement. It's not a new protocol — it's a specification for how existing USDC infrastructure can be used by machines. The document is a draft, and Circle hasn't announced a finalization timeline. But the move signals the company sees machine payments as a core use case for USDC.
A glimpse at the draft
The draft lives on paymentauth.org, a site dedicated to machine-to-machine payment standards. It walks through a charge flow — how an agent requests payment, how the payee authorizes it, and how the USDC settles. The spec is open for anyone to read and build against. Whether wallet providers, exchanges, and AI platforms adopt it will determine how quickly the standard gains traction.
