Unverified50% confidenceEventExact time
In the 2026-10-02 incident, the exposed list omitted PAYMENT-REQUIRED and PAYMENT-RESPONSE, so the browser client could receive the 402 but could not parse the acceptable payment terms.
1
Sources
50%
Confidence
Medium-term (~90 days)
Relevance
10/18/2026
First Seen
Valid until: 1/16/2027
Sources
Related Entities
Related Claims
UnverifiedWhen a browser-side agent initiates a paid call, if the preflight request fails due to a missing header name, no 402, 400, or timeout will appear in the server logs, because the request never left the browser.72% similarUnverifiedA '403 Your account is currently unavailable' error typically points to scenarios such as risk control false positives, payment-related issues, or terms of service violations66% similarUnverifiedHTTP status code 400 indicates a malformed request body, 401 indicates invalid or missing credentials, 403 indicates insufficient permissions, 429 indicates a rate limit has been triggered, and 5xx points to server-side issues.65% similarUnverifiedIn the x402 flow, when the server returns a 402 response, the response body contains payment requirement metadata such as amount, currency, and payee address; the client parses this and automatically completes the payment, then resends the request with a payment proof.65% similarUnverifiedThe anti-loop guard throws PaymentNotAcceptedError when a retry request carrying a payment-signature returns 402 again, and never pays twice for the same request.65% similar
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https://kongchang.com/claim/1062739API
curl https://kongchang.com/api/v1/knowledge/claims/1062739MCP
get_claim(id=1062739)