Base64 decodes to non-JSON

Quirk · GET /api/x402/header-base64-not-json · 402 / Challenge Construction

The PAYMENT-REQUIRED header is valid base64 but decodes to bytes that are not JSON.

Explanation

The header is valid base64 but decodes to bytes that are not JSON, so parsing fails after a successful decode. The merchant is encoding the wrong payload into the challenge.

What to watch

JSON parsing fails after a successful base64 decode.

Facilitator

Settled against the live Radius testnet facilitator (https://facilitator.testnet.radiustech.xyz). A valid payment runs a real /verify and /settle on-chain.

Metadata

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