HTTP 402 was reserved for payments long before x402

RFC 9110 still lists 402 Payment Required as reserved. x402 is an overlay, not a new status code.

HTTP 402 Payment Required has been reserved in the HTTP status registry for decades. RFC 9110 continues that reservation. x402, MPP and Cloudflare pay-per-crawl are overlays that finally put a payload on a reserved code. They are not IETF replacements of HTTP.

Why it matters

Explainer accuracy matters. Calling x402 “a new HTTP status” is wrong; calling it a payment protocol that uses 402 is right.

Source: RFC 9110

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