Ethereum Foundation's zkAPI goes live on mainnet for private AI API payments
In brief
- zkAPI is live on Ethereum mainnet, the Ethereum Foundation announced Thursday.
- zkAPI users deposit into a vault and use zero-knowledge proofs to show they have enough credit.
- zkAPI issues short-lived API keys with predefined spending limits.
- The launch builds on a February proposal by Davide Crapis and Vitalik Buterin.
- Prompt contents, IP addresses and timing remain visible to providers.
How the vault and proofs work
Users deposit funds into an Ethereum vault, then use zero-knowledge proofs to show they've got enough credit for API requests (without revealing which deposits are theirs). That's the mechanism described in a post from Vittorio Rivabella, AI coordinator at the Ethereum Foundation's dAI team, as reported by Cointelegraph.
zkAPI issues short-lived API keys with predefined spending limits. Prompts go directly to the AI provider, while usage is settled separately through the payment layer. One immediate use case cited is paying for AI without linking the payment to a user.
The project has also released a local client, a software development kit and a browser-based AI chat implementation, so it isn't just a spec sitting in a research post anymore.
From February proposal to mainnet
The launch follows a February proposal by Ethereum Foundation researcher Davide Crapis and Ethereum co-founder Vitalik Buterin for ZK-based API usage credits. They presented the concept as a way to give users private, prepaid access to AI and other metered APIs.
This release turns that design into a working mainnet implementation.
What zkAPI doesn't hide
So what actually stays private? The billing side does. The rest is a different story.
zkAPI doesn't hide prompt contents or network metadata from providers, according to Cointelegraph. That means users can still potentially be linked across sessions through IP addresses, timing or request contents, even if the payment itself can't be tied back to a specific deposit.
It's private payments, not full anonymity. The proofs cover who paid; they don't cover what a user sends to the provider or where it's sent from, and the people behind zkAPI aren't claiming otherwise.
Frequently asked questions
How does zkAPI let users pay for AI without revealing who they are?
Users deposit funds into an Ethereum vault, then use zero-knowledge proofs to show they have enough credit for API requests without revealing which deposits are theirs. zkAPI issues short-lived API keys with predefined spending limits, and usage is settled separately through the payment layer.
Is zkAPI fully anonymous?
No. zkAPI doesn't hide prompt contents or network metadata from providers. Users can still potentially be linked across sessions through IP addresses, timing or request contents, so the privacy applies to billing identity, not to the requests themselves.
Where did the zkAPI design come from?
The launch follows a February proposal by Ethereum Foundation researcher Davide Crapis and Ethereum co-founder Vitalik Buterin for ZK-based API usage credits. The mainnet release turns that design into a working implementation, built with the Open Anonymity Project.
