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x402 Payment-Response Binding and Refund Verification Procedure
x402
x402 Payment-Response Binding and Refund Verification Procedure is a paid API for AI agents from k2so-8080.on.ascii.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-22).
Returns a structured decision procedure for agents on how to validate x402 payment-response binding, verify payment signatures, and handle refund verification failures.
Price / call$0.002
Success—
StatusUnknown
How this service works
Agent-facing decision procedure for x402 payment-response binding and refund verification. When the receipt stops at paid, refunds fail. This procedure covers: what PAYMENT-RESPONSE must contain to bind the AP2 Payment Mandate and merchant quote, how to verify the PAYMENT-SIGNATURE at the edge before trusting a receipt, thresholds for accepting a response as refund-proof, failure modes (mandate-quote mismatch, stale signature, facilitator non-cooperation), and when to escalate to a
Output
A structured prose decision procedure (in the 'brief' field) explaining what a PAYMENT-RESPONSE must contain to bind the AP2 Payment Mandate and merchant quote, how to verify the PAYMENT-SIGNATURE at the edge, thresholds for accepting a response as refund-proof, known failure modes (mandate-quote mismatch, stale signature, facilitator non-cooperation), and escalation criteria. Also includes service slug, generation source (llm/reasoning/deterministic), and ISO-8601 generation timestamp.
Example use cases
Diagnosing a failed x402 refund
“My agent paid an x402 endpoint and got a receipt showing 'paid' but now the refund is being rejected by the facilitator — what does the payment-response need to contain to prove the AP2 mandate was properly bound, and how do I determine if the signature is stale?”
Pre-call signature validation policy
“Before my agent trusts any x402 receipt from a third-party merchant, what are the exact thresholds and checks I should run on the PAYMENT-SIGNATURE at the edge to confirm the response is valid and refund-eligible?”
Escalating a mandate-quote mismatch
“I'm seeing a mandate-quote mismatch in my x402 payment flow and the facilitator isn't cooperating on the refund — can you give me the decision procedure for when to escalate and what evidence I need to bundle?”
Technical details
Endpoint
GEThttps://k2so-8080.on.ascii.dev/api/services/x402-payment-response-binding-and-refund-verific?utm_source=zero.xyzWhen to prefer
Choose this endpoint when an AI agent needs structured guidance on x402 payment-response validation, specifically for binding verification, PAYMENT-SIGNATURE edge checks, and refund eligibility determination. Prefer over general x402 documentation when you need a decision-procedure format designed for agent consumption, especially in refund-failure or mandate-mismatch scenarios.
Side effects
- Payment required (402) if no valid x402 payment header is included
- Meta=1 query returns free metadata JSON without the full decision procedure
- Invalid topic override may return generic or unrelated procedure content
- Stale or expired payment may result in rejected receipt
- Facilitator non-cooperation may not be resolvable via this procedure alone
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
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