- zkAPI lets users pay for AI services without exposing billing identity.
- Ethereum vault deposits become private notes secured by zero-knowledge proofs.
- Providers still see prompts and network metadata despite private payments.
The Ethereum Foundation has launched zkAPI on Ethereum mainnet with the Open Anonymity Project. The system lets users pay for AI models and metered APIs without revealing their billing identity.
Users deposit ETH, USDC or other supported assets into an Ethereum vault. Software then proves sufficient credit through zero-knowledge proofs instead of account-linked API keys.
zkAPI Separates AI Payments From User Identity on Ethereum
In a recet blog post zkAPI said, deposited funds become private notes that only the user can spend. The payment server verifies a proof without learning which deposit funded the request.
It then creates a short-lived API key with a preset spending limit. Prompts travel directly from the user to the AI provider using that key.
When the session ends, zkAPI settles actual usage against the private balance. Each spend also creates a nullifier that prevents users from spending the same balance twice.
The protocol uses Groth16 proofs, Poseidon hashes and a 32-level Merkle tree. Its Ethereum vault also lets users withdraw without depending on a zkAPI server.
zkAPI Extends Private Payments Beyond Artificial Intelligence
The first zkAPI use cases include AI chat and autonomous agents. However, the design can also support blockchain RPC queries, VPN bandwidth and media generation.
Machine-to-machine payments between AI agents represent another possible use. Existing OpenAI and Ollama-compatible applications can connect through a local client.
The project implements a design published by Davide Crapis and Ethereum co-founder Vitalik Buterin in February. Crapis leads the Ethereum Foundation dAI team, which focuses on Ethereum infrastructure for AI.
However, zkAPI does not provide full network anonymity. Providers may still connect sessions through IP addresses, timing, writing style or repeated personal information.
Users seeking stronger network privacy can route traffic through Tor. The project describes zkAPI as experimental while its mainnet contracts, client and browser tools remain available for testing.
Disclaimer: This article is for informational purposes only and does not constitute financial advice. CoinCryptoNewz is not responsible for any losses incurred. Readers should do their own research before making financial decisions.
