zkAPI makes AI billing unlinkable on Ethereum

The Ethereum Foundation’s zkAPI launched on mainnet with a 32-level Merkle tree for private usage credits, separating an API provider’s view of prompts from the payment layer’s view of identity. In its official zkAPI announcement, the Foundation says the client mints short-lived, dollar-capped keys and exposes standard OpenAI and Ollama APIs, while warning that stable IPs and repeated prompt details can still re-link sessions. Builders handling sensitive AI workloads can treat zkAPI as an experimental billing boundary—not network anonymity or content confidentiality—and compare it with the archive’s analysis of agent credit budgets before putting it between production requests and a provider.