zkAPI targets the billing trail behind AI requests
Experimental API credits leave providers able to see prompts
The Ethereum Foundation introduced zkAPI on October 1 as a way to separate API payments from usage. Open Anonymity built it with the foundation.
How access works
The design uses cryptographic proof that prepaid credits can cover usage. A temporary API key carries a spending cap and an expiration time.
In the announcement’s direct mode, prompts go to the inference provider without passing through the payment server. It also describes a relay mode that exposes traffic to the intermediary.
What providers still see
The foundation says providers still receive prompts and network information such as IP addresses. Timing and repeated content, including personal details, writing style or conversation history, can reconnect sessions.
Teams evaluating the tool should map each observer separately. Hiding a payment link does not establish that the conversation itself is confidential.
The software remains experimental
The underlying design appeared on Ethereum Research on February 11. A standalone client prerelease followed on September 30. The latest listed client prerelease is 0.1.6 from October 2.
The current repository describes native ETH funding and labels the protocol experimental. Its proof setup was generated by one party. The setup notes say no multiparty ceremony has taken place.
ByteForward reviewed the announcement and published documentation. We have not run the software or audited the contracts.
Archival padlock photograph by Estormiz / CC0 / Wikimedia Commons, taken March 7, 2025. Used unchanged as a privacy illustration, without implying that zkAPI provides complete protection.
