test402

x402: No version field

A deliberately broken x402 endpoint charging 0.0001 USDC on Base Sepolia, advertising x402.org.

Pick a protocol

x402 uses its own PAYMENT-REQUIRED header. MPP uses the standard HTTP auth framework, with no facilitator.

Protocol

New to these? Read what x402 and MPP put on the wire.

Pick a network

Testnets only. Nothing here can move real money.

USDC, 6 decimals

Set the price

Amounts are atomic units of the asset, so no decimal point.

= 0.0001 USDC

Defaults to this network's burn address.

Pick a facilitator

What the challenge advertises for verify and settle. test402 issues challenges; it never settles.

Public testnet facilitator from the x402 docs.

Sign offers and receipts

The offer-receipt extension: a signed commitment to the terms on the 402, and a signed statement of delivery on the 200.

The challenge carries no signed offer, and a paid retry returns no receipt. This is the default, and the shape every test here had before the extension existed.

Choose a behavior

Compliant by default. Every deviation is named, and never on by accident.

The challenge omits x402Version. A client that assumes a version is guessing.