deliberately brokenMPP

MPP legacy network name

An MPP challenge whose request payload names the network base-sepolia rather than eip155:84532.

Your client should Refuse it rather than guess which chain it means.

Protocol: MPP
Network: Base Sepolia
Price: 0.0001 USDC
Scheme: exact
Facilitator: x402.org
Behavior: Legacy network name

The challenge names the network the old way (base-sepolia, not eip155:84532). A strict client should refuse it rather than guess the chain.

Customize this test

Your endpointLegacy network name

/api/mpp?quirk=v1-network-name

Try it

curl -i "https://test402.com/api/mpp?quirk=v1-network-name"

Returns 402 whose network is the legacy spelling -- in the x402 requirement, or inside the MPP request payload.

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="eyJhbW91bnQiOiIxMDAiLCJjdXJyZW5jeSI6IjB4MDM2Q2JENTM4NDJjNTQyNjYzNGU3OTI5NTQxZUMyMzE4ZjNkQ0Y3ZSIsIm1ldGhvZERldGFpbHMiOnsiY2hhaW5JZCI6ImJhc2Utc2Vwb2xpYSIsImNyZWRlbnRpYWxUeXBlcyI6WyJhdXRob3JpemF0aW9uIiwidHJhbnNhY3Rpb24iXSwiZGVjaW1hbHMiOjYsInBlcm1pdDJBZGRyZXNzIjoiMHgwMDAwMDAwMDAwMjJENDczMDMwRjExNmRERUU5RjZCNDNhQzc4QkEzIn0sInJlY2lwaWVudCI6IjB4MDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDAwMDQwMiJ9", 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=v1-network-name"
}