economics

Stablecoin

A cryptocurrency pegged to a fiat reference (typically USD) — the unit of account for x402 payments. USDC is the default in Mission Control.

A stablecoin is a cryptocurrency designed to maintain a stable price against a reference asset, usually 1:1 against the US dollar. The major dollar stablecoins are USDC (issued by Circle), USDT (Tether), and DAI (MakerDAO).

Mission Control settles every x402 payment in USDC by default on Base mainnet (eip155:8453) or Base Sepolia testnet (eip155:84532). The choice of USDC + Base reflects the Coinbase x402 ecosystem: native CDP integration, the lowest fees on a major L2, and the best regulatory clarity for stablecoin-denominated B2B payments.

x402— An open standard for HTTP-native programmatic payments using stablecoins, hosted by the x402 Foundation under the Linux Foundation.

Where this term shows up

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