# X402 Refund Receipt Check

> X402 Refund Receipt Check is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-19).

Validates a caller-supplied x402 refund receipt by checking its identifier, amount, and status, returning acceptance or rejection with mismatch reasons and normalized evidence.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/x402-refund-receipt-check?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-refund-receipt-check-8e518531
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gLyLVm59U08kjMM-reUh2

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability x402-refund-receipt-check-8e518531 -d '<json body>'
```

Example prompt: Before I accept this refund, can you check this x402 refund receipt and tell me whether it's valid — specifically verify its identifier, amount, and status match what was expected, and flag any mismatches?

## When to prefer this

Use this endpoint when operating in an x402 payment or agent delivery workflow and you need an in-memory, stateless validation of a refund receipt before accepting or paying. Prefer this over manual inspection when you need normalized evidence and explicit accept/reject verdicts without retaining any data externally. It is particularly useful when the receipt metadata is caller-supplied and potentially untrusted.

## Known failure modes

- Receipt object exceeds 128 properties limit — request rejected
- Malformed or missing receipt field — validation cannot complete
- Ambiguous or unrecognizable receipt structure — mismatch reasons returned with rejection
- Upstream computation error — internal server error response
- Receipt with no recognizable identifier or amount fields — rejection with explanation

## How this service works

X402 Refund Receipt Check: X402 Refund Receipt Check checks caller-supplied refund receipt identifiers, amount, and status from bounded caller-supplied values without an external provider. Call X402 Refund Receipt Check before paying for or accepting an x402 or agent delivery assembled from caller-supplied challenge and result metadata. Returns contract-specific checks, normalized evidence, mismatch reasons, and an explicit acceptance or rejection status for X402 Refund Receipt Check as version…

## Output

Returns a structured result containing contract-specific check outcomes, normalized evidence extracted from the receipt, a list of mismatch reasons if any discrepancies were found, and an explicit acceptance or rejection status verdict for the submitted refund receipt.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "receipt": {
   "type": "object",
   "description": "Receipt supplied to X402 Refund Receipt Check; used only for this bounded calculation and processed in memory without retention.",
   "maxProperties": 128,
   "additionalProperties": true
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "receipt": {
    "status": "queued",
    "refund_id": "refund-1",
    "amount_raw": "1000",
    "payment_id": "pay-1"
   },
   "shape_valid": true,
   "missing_fields": []
  },
  "schema": "delx/util-x402-refund-receipt-check/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "eed8a44348546c38e110e86becc0cf20609c4043c2d9579d6b2d25468d2f7566",
   "external_calls": 0
  },
  "operation": "delivery_contract:x402_refund_receipt_check"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-refund-receipt-check-8e518531/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)