deliberately brokenMPP

MPP amount as a number

An MPP request payload whose amount is a bare JSON number instead of an atomic-units string.

Your client should Refuse it, or read the amount as a big-integer string.

Protocol: MPP
Network: Base Sepolia
Price: 0.0001 USDC
Scheme: exact
Facilitator: x402.org
Behavior: Amount as a number

The amount is a JSON number, not the atomic-units string the spec requires. A client that does Number(amount) loses precision above 2^53.

Customize this test

Your endpointAmount as a number

/api/mpp?quirk=amount-as-number

Try it

curl -i "https://test402.com/api/mpp?quirk=amount-as-number"

Returns 402 whose amount is a bare JSON number rather than a quoted string.

Response it will return (HTTP 402)

WWW-Authenticate: Payment id="<bound per request -- run the curl to see it>", realm="test402.com", method="evm", intent="charge", request="eyJhbW91bnQiOjEwMCwiY3VycmVuY3kiOiIweDAzNkNiRDUzODQyYzU0MjY2MzRlNzkyOTU0MWVDMjMxOGYzZENGN2UiLCJtZXRob2REZXRhaWxzIjp7ImNoYWluSWQiOjg0NTMyLCJjcmVkZW50aWFsVHlwZXMiOlsiYXV0aG9yaXphdGlvbiIsInRyYW5zYWN0aW9uIl0sImRlY2ltYWxzIjo2LCJwZXJtaXQyQWRkcmVzcyI6IjB4MDAwMDAwMDAwMDIyRDQ3MzAzMEYxMTZkREVFOUY2QjQzYUM3OEJBMyJ9LCJyZWNpcGllbnQiOiIweDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDA0MDIifQ", expires="2026-01-01T00:05:00Z"

{
  "type": "https://paymentauth.org/problems/payment-required",
  "title": "Payment Required",
  "status": 402,
  "detail": "test402 challenge",
  "note": "test402 scenario. quirk=amount-as-number"
}