Ethereum Foundation launches private API payments

The Ethereum Foundation and Open Anonymity Project released zkAPI, a system for paying for metered APIs without attaching each request to a billing identity. Users deposit ETH, USDC or other supported credits into an Ethereum vault and later authorise bounded spending with zero-knowledge proofs.

The provider sees the request and a short-lived usage key, while the payment layer verifies that funded credits exist without learning which deposit belongs to the user. The contracts are live on Ethereum mainnet, and the client can expose familiar OpenAI-compatible interfaces to local applications.

The construction hides the payment link, not everything about a request. Providers can still see content and network metadata such as an IP address, so network anonymity and prompt privacy remain separate problems.