Measurement
pay-per-call
Pay-per-call means the client pays for a single request, then repeats that when it wants another. x402's default HTTP flow is pay-per-call: a 402 challenge, a payment, a response. In this index's use-case rollup, pay-per-call is also the residual pattern when a service is not recurring and not high frequency.
Explanation
The use-case job labels a service high frequency when it has at least 10,000 calls in 30 days and a catalog price under $0.01. It labels recurring when there are at least 20 calls, no more than three payers, and at least 30 calls per payer. Everything else in the classified catalog is pay-per-call. The labels describe the catalog's call pattern. They do not change the settled amount.
MPP sessions are the metered alternative: one deposit, many vouchers, fewer settlements. A session can bill per token or per second and still settle in batches. Those settlements are MPP volume. They are not rebooked as one x402 call per voucher. The use-case page links each category, with its live volume, to the underlying sellers.
Live data
Related terms
Sources
- How x402 works — Coinbase Developer Platform
- Sessions: low-cost high-throughput payments — MPP
- Agent GDP methodology — Agent GDP