1. Request
An agent requests a paid API resource.
Internet-native payments
Software can pay for the capabilities it needs.
x402 is an open protocol for HTTP-native payments. Instead of requiring a traditional subscription or long-lived customer account, a resource can require payment as part of the request flow.
x402
2. Payment
The payment requirement is handled through the x402 flow.
3. Resource
Once paid, the service returns the requested structured result.
Where we fit
x402 is the rail. Preflight Stack is the utility layer.
Preflight Stack builds focused capabilities on top of the payment rail: dependency preflight decisions, random selection, and future agent-facing services.
Why it matters
- Pay-per-request economics
- Useful for machine-to-machine interactions
- No need to bundle every capability into one platform
- Services can stay small, composable, and easy to understand