The setup uses USDC and the HTTP 402 payment model to let autonomous software pay per request without traditional API keys, subscriptions or invoicing.
0x Protocol has opened its Swap API to AI agents for $0.01 per request in USDC, using a pay-per-request model tied to the HTTP 402 "Payment Required" concept rather than traditional API keys, subscriptions or invoicing. The approach is designed to let autonomous software pay directly from a wallet for token quotes, routing or swaps, potentially making access to decentralized liquidity more modular for bots, wallets, trading tools and other agentic workflows. The development remains an early infrastructure step rather than evidence of broad AI-agent trading adoption, with security, permissioning, wallet controls and payment reliability still important hurdles before such systems can safely scale.