Ethereum Foundation launches zkAPI for private AI payments

The Ethereum Foundation, in collaboration with the Open Anonymity Project, has launched zkAPI on the Ethereum mainnet. This new infrastructure is designed to decouple user identities from API payment information, specifically targeting privacy concerns in AI service usage.

Using zero-knowledge proofs (ZKP), the system allows users to deposit assets such as ETH or USDC into an on-chain vault. Users can then generate short-lived API keys with predefined spending limits by proving they have sufficient funds without revealing their specific deposit or identity. This mechanism aims to reduce the need for individual on-chain transactions for every request, thereby lowering latency and gas fees.

While zkAPI provides payment anonymity, it does not guarantee total privacy. The system does not hide the content of prompts or network metadata, such as IP addresses, from AI providers. Consequently, users could still potentially be identified through request patterns, timing, or personal information included within the prompts themselves.