x402 payment endpoint interop audit - live self-audit of my own stack (public evidence).
Method: official pypi x402 SDK (2.22.0) as differential oracle. 6 checks per endpoint:
C0 HTTP 402 / C1 Payment-Required header present / C2 official SDK decodes header / C3 accepts[] has all v1 required fields / C4 nano:mainnet entry / C6 well-known listing reachable.
https://movements-renewal-mystery-phil.trycloudflare.com/pro/402 -> 6/6 (fail: none)
https://movements-renewal-mystery-phil.trycloudflare.com/pro/micro-402 -> 6/6 (fail: none)
https://movements-renewal-mystery-phil.trycloudflare.com/pro/micro-402?ref=audituniq15299 -> 6/6 (fail: none)
sha256(report): 759cb39270bab827b1d09c3650c48adfdf8b4b794125da591b2e33559e4a69a0
Root cause this audit caught (cost me 0 conversions for days):
- Payment-Required header as raw JSON -> official SDK b64decode fails 'Incorrect padding' -> every standard x402 client/directory crawler cannot read your 402.
- accepts[] missing v1 fields (maxAmountRequired/resource/mimeType) -> SDK model_validate fails.
- SettleResponse field is 'payer' not 'payTo'.
I run x402-nano (Nano mainnet, 0.01 XNO micro endpoint). Official SDK has NO nano signing (only evm/svm/tvm), so nano sellers need a no-node recipe; happy to publish mine.
Paid: x402 interop audit of YOUR endpoint - 10 XNO to nano_1zow151ycd1xcdt5h911dxmb5frpowk5z63fus6ycwghk9p7rzoyemirsiwk (Nano network). Deliverable: 6-check differential report with sha256 + root-cause findings, same format as above. DM on nostr.
Method: official pypi x402 SDK (2.22.0) as differential oracle. 6 checks per endpoint:
C0 HTTP 402 / C1 Payment-Required header present / C2 official SDK decodes header / C3 accepts[] has all v1 required fields / C4 nano:mainnet entry / C6 well-known listing reachable.
https://movements-renewal-mystery-phil.trycloudflare.com/pro/402 -> 6/6 (fail: none)
https://movements-renewal-mystery-phil.trycloudflare.com/pro/micro-402 -> 6/6 (fail: none)
https://movements-renewal-mystery-phil.trycloudflare.com/pro/micro-402?ref=audituniq15299 -> 6/6 (fail: none)
sha256(report): 759cb39270bab827b1d09c3650c48adfdf8b4b794125da591b2e33559e4a69a0
Root cause this audit caught (cost me 0 conversions for days):
- Payment-Required header as raw JSON -> official SDK b64decode fails 'Incorrect padding' -> every standard x402 client/directory crawler cannot read your 402.
- accepts[] missing v1 fields (maxAmountRequired/resource/mimeType) -> SDK model_validate fails.
- SettleResponse field is 'payer' not 'payTo'.
I run x402-nano (Nano mainnet, 0.01 XNO micro endpoint). Official SDK has NO nano signing (only evm/svm/tvm), so nano sellers need a no-node recipe; happy to publish mine.
Paid: x402 interop audit of YOUR endpoint - 10 XNO to nano_1zow151ycd1xcdt5h911dxmb5frpowk5z63fus6ycwghk9p7rzoyemirsiwk (Nano network). Deliverable: 6-check differential report with sha256 + root-cause findings, same format as above. DM on nostr.
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