Arc has officially launched agentic payments, integrating Circle’s Facilitator Service to allow AI agents and developers to accept USDC across Arc, Base, and Polygon PoS without operating separate gas wallets or relayers. The rollout, announced on September 19, 2026, is built on the open x402 protocol, which standardizes payment requests using the web’s HTTP 402 Payment Required status code.
Under the new flow, a buyer or AI agent requests a paid resource from a seller’s API; the seller responds with the price, target network, and payment address; the buyer signs an offchain EIP-3009 authorization; the seller sends that signature to Circle; and Circle screens both addresses, pays the settlement gas, and submits the USDC transfer. After confirmation, the seller receives a transaction hash and releases the resource.
Circle does not eliminate gas; it moves it out of sight. The Facilitator Service broadcasts each transfer through Circle’s relayer and funds the native gas on the relevant chain. Buyers no longer need to maintain a separate balance of ETH or POL just to move USDC, which removes a major friction point for machine-to-machine payments and API monetization.
Circle checks that the signature is valid, that the buyer holds sufficient USDC, and that the recipient matches the seller’s designated address. However, the company says it does not verify the purpose of a transaction or the scope of an AI agent’s authority. Wallet-level controls such as spending ceilings, restricted recipients, and limited balances remain the responsibility of the application or its owner.
The service creates an operational dependency: sellers rely on Circle to accept requests, complete screening, keep the relayer funded, and submit transactions. Circle states it does not hold or control buyer funds, but production use requires a Circle API key. Settlement conditions also differ by chain: Arc settlements are described as final, while Base and Polygon PoS settlements are not guaranteed against blockchain reorganizations.
The launch comes as agentic commerce gains traction, with developers able to monetize datasets, APIs, and AI-powered digital services using USDC as a payment layer. Arc’s ecosystem further includes Uniswap v2, v3, v4, and UniswapX infrastructure, placing payment settlement and onchain liquidity within the same network, though the systems are not automatically connected.
