zk402 is a next-generation privacy protocol designed to bring confidential, verifiable, and seamless on-chain transactions to the broader blockchain ecosystem. The project was created to combine zero-knowledge cryptography with the x402 payment infrastructure, forming a system where users can transact freely without revealing sensitive information while maintaining full on-chain validity. Today, most blockchain transactions are fully transparent and easily traced, which exposes financial data and limits privacy. zk402 is built to solve this problem by providing a privacy layer that protects users and businesses while keeping transactions trustless and verifiable.