Unverified50% confidenceFactExact time
Sending a forged X-PAYMENT header to the two endpoints returns 402 and a malformed_payment_header error from pay.openfacilitator.io
1
Sources
50%
Confidence
Short-term (~14 days)
Relevance
10/12/2026
First Seen
Valid until: 10/26/2026
Sources
Related Entities
Related Claims
UnverifiedIn the x402 marketplace interface implementation, the discovery document returning a machine-readable manifest returns HTTP 200 rather than a 402 challenge, while the actual 402 challenge is issued via the PAYMENT-REQUIRED header on the paid route.55% similarUnverifiedThe core idea of the X402 protocol is to embed payment into the HTTP request process: the server returns a 402 status code with payment details, the agent signs an authorization from a crypto wallet, completes the payment, and retries the request.55% similarUnverifiedWhen a rate limit dimension of an API provider is hit, the provider returns an HTTP 429 error.54% similarUnverifiedHTTP status code 401 indicates authentication failure, 429 indicates rate limiting has been triggered, and 500 indicates a server-side error.54% similarUnverifiedWhen an agent holding a read-only token attempts to perform a write operation, the MCP server returns 403 Forbidden and indicates Insufficient Scope.51% similar
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