Ethereum Foundation introduces zkAPI for private, identity-less API usage

zkAPI allows users to pay for metered API usage using private credits deposited into an Ethereum vault, without revealing personal identity to the API provider. This system uses zero-knowledge proofs to authorize bounded usage, separating payment from identity. Users deposit credits (ETH, USDC, etc.) once, and subsequent spending is authorized by a proof, ensuring the provider sees requests but not the billing identity, and the payment layer sees spend but not the requests. This addresses the current model where every AI API call links an identity to usage records, which is critical given that prompts can contain sensitive personal information.