http-402 tag

Publications

Ordered by date created, newest first. All 5 publications are shown on this page.

How an x402 payment works, step by step, from a real 402 response 2026-10-21 · article
Decode a live x402 v2 challenge header by header: the 402, PAYMENT-REQUIRED, the signed EIP-3009 authorization, settlement and the receipt.
What an x402 seller should do that the spec doesn't require 2026-10-21 · article
Eight seller behaviors beyond the x402 spec, each running on a live endpoint: refuse before charging, recover purchases, pin payees, one catalog.
Repeat x402 purchases with X-Payment-Recovery: get the same bytes after a dropped connection 2026-10-14 · article
How an x402 seller returns an already-paid response when the buyer repeats the same signed request with a private X-Payment-Recovery token.
Refuse before you charge: how an x402 API stops billing agents for bad requests 2026-10-13 · article
Validate the body and refuse with 400, 415 or 422 before any 402 challenge, and cancel settlement if the handler fails. Real live responses included.
Never trust the payee in a 402 challenge: buyer-side x402 payee verification 2026-10-13 · article
An x402 buyer must take the payee from its own authority, not the seller's 402 challenge. How an expectedPayTo check, a budget and quote-drift refusal work.