USDC is the default settlement asset across x402, Base and several agent rails

Circle’s dollar token is the unit most machine-payment demos actually move.

Public x402, CDP and Base documentation consistently price and settle first-wave machine payments in USDC. Circle’s role is issuer infrastructure rather than a protocol competitor. zFinia treats USDC availability, chain support and attestation as market plumbing, not as a price prediction.

Why it matters

A machine economy still needs a unit of account. Today that unit is usually USDC, which concentrates issuer, chain and facilitator risk.

Source: Circle

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