Payment rails without passengers

The five-layer payment infrastructure for AI agents is real and shipping. But payment rails are normally the last mile of a commercial stack, the piece you build once transaction volume materialises, not before. Here the infrastructure is ahead of the economics.

Reframe what the platforms are doing. Stripe, Google and OpenAI aren’t building this because agent commerce is viable. They’re building it because being late to a standard is catastrophic if it becomes viable. It’s a coordination game among platforms, not evidence of demand.

So protocol compatibility is cheap insurance, not a market-entry gate. The real gate is unit economics: until an agent demonstrably earns more per task than it costs to run, the payment infrastructure is speculative plumbing.