In the AI era, zkAPI is crucial for expanding Ethereum's application scenarios. zkAPI enables: paying for AI APIs with ETH/USDC while maintaining privacy (the other party doesn’t know who made the payment). Specifically, Currently, AI service providers charge per use via APIs, typically requiring an account + API key + linked payment method. Every time you ask a question, your conversation history and payer info can be tied together. With zkAPI, “payment” and “who’s using it” can be separated, so you’re no longer forced to bind your identity, payment, and conversations to the same intermediary. Here’s how it works: You deposit some ETH or USDC into a vault contract on Ethereum mainnet. The deposit transaction itself is visible on-chain, but the balance turns into “private tokens” that only you can spend. Future spending can’t be traced back to the specific deposit. When you want to use it, your device generates a zero-knowledge proof. This proof shows you have enough prepaid balance to cover the API call, but it doesn’t reveal which deposit it came from or who you are. Once verified, the system gives you a temporary key with a spending limit. With this key, you can directly interact with the AI service provider. The AI service provider can see your request content, but they won’t know who’s paying. The payment layer can see how much was paid but won’t see your request content. This way, the payment processor can’t see the content, the AI model operator doesn’t know who’s paying, and on-chain activity only shows deposits and withdrawals, not what the money was spent on. The funds are stored in Ethereum contracts, not on a company’s server, so users can withdraw anytime without needing the other party’s cooperation. Currently, zkAPI can run on Ethereum mainnet. However, the team says it’s still experimental. Also, it only breaks the link between “payer identity” and “request.” IP/network traces or personal info in prompts could still tie different sessions together. In summary, Ethereum is positioning itself as the “cash layer” in the AI era. Smart contracts already solve the issue of transferring money without banks; zkAPI solves the issue of calling models without needing an account. And it’s not limited to AI—any pay-per-use API can adopt this credit system. #Ethereum #zkAPI #AI #Crypto #Web3 #ETH $ETH $USDC