Agent Payment Layers Are Fragmenting — What Developers Need to Know Now

Two different agent payment rails shipped in the last month. They solve the same problem differently. If you're building a service that agents pay for, you now have a choice that didn't exist 60 days ago. Here's what they are and when to use each. What just happened March 17, 2026: x402 V2 with World/AgentKit Coinbase's x402 protocol got its first major upgrade. The V2 integration with World and AgentKit adds real-identity payments to the existing machine-to-machine micropayment flow. World is Sam Altman's human identity verification project — World ID is a proof of personhood tied to a biometric scan. What this means practically: an agent can now attach a verified human identity to an x402 payment. The endpoint knows the agent's operator is a real person, not just an anonymous wallet address. This changes the trust surface for high-stakes transactions. February 2026 (testnet live): Circle Nanopayments on Base Circle launched a USDC micropayment layer purpose-built for machine-to-machi