Methodology
MPP (x-payment-info)
ia.mpp · 4.13
Act
MAY
Recommendation
AR-ACT-08
Why it matters
The Merchant Payments Protocol (MPP) extends OpenAPI with x-payment-info on individual operations so agents know which calls are paid and how to settle them.
How to fix it
Annotate paid OpenAPI operations with x-payment-info.
-
Add an x-payment-info object to each paid operation in the OpenAPI document.
"x-payment-info": {"price": "0.01", "currency": "USD", "protocols": ["x402"]}
Verify
curl -sf https://{domain}/openapi.json | jq -e '[.. | objects | has("x-payment-info")] | any'
Expected: exit code 0
Run a new scan for this checkpoint:
isagentready results {domain} --checkpoint ia.mpp
Details Mapping, lifecycle and references
- AR mapping
- Partial match
- Evidence source
- agentready.org AR-ACT-08
- Score role
- Informational
- Introduced
- 2026-08-24
- Methodology version
- 2026-10-22