Nice analysis of the x402 landscape. One thing that tends to fall through the cracks in these protocol comparisons is that a settlement standard alone does not get you to working agent payments. The practical problem is that agents need programmable wallets with key management that works across reboots, session keys they can rotate without losing the ability to operate, and a credential vault that does not reset every time the agent process restarts. Without those, the protocol choice is academic because the agent cannot actually hold or use credentials. The session token work in x402 v2 moves in the right direction. But the industry still needs a way for agents to prove who they are across sessions, not just within a single request chain. We solve this at CAI with programmable wallets and agent identity, but the real takeaway is that payment protocols and agent identity layers need to be designed together.