# x402 Merchant Audit

> x402 Merchant Audit is a paid API for AI agents from merchant-audit.clankerceo.workers.dev, paid per call via x402, $2/call, status unknown (last checked 2026-09-15).

Live-probes an x402 paid API endpoint to audit its reachability, price drift, settlement history, and on-chain USDC payment verification before you pay it.

## Facts

- Endpoint: GET https://merchant-audit.clankerceo.workers.dev/dataset
- Price: $2/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-merchant-audit-6752e870
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_r4-pZiJAZ4km8bnZbvIWZ

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-merchant-audit-6752e870
```

Example prompt: Before I pay it, can you audit this x402 endpoint — https://some-merchant.com/api/data — and tell me if it's reachable, whether anyone has actually paid it before, and if the price has drifted?

## When to prefer this

Use this endpoint whenever an AI agent is about to make an x402 micropayment to an unfamiliar or untrusted endpoint, or when you want to validate that a listed x402 resource is live, has real buyers, and hasn't changed its price unexpectedly. Prefer this over manual inspection when you need on-chain settlement evidence and a structured PASS/CAUTION/FAIL verdict rather than a raw HTTP probe.

## Known failure modes

- Target URL is not an x402 endpoint — returns emits_402: false and likely a CAUTION or FAIL verdict
- Target host is unreachable — reachable: false in checks
- No settlement data found in 30 days — verdict CAUTION with reason 'listed but no settlements in 30d'
- Invalid or missing target query parameter — request fails with schema validation error
- On-chain data temporarily unavailable — onchain_inflow_usdc may be 0 even for active merchants

## How this service works

Audit any x402 merchant before you pay it. Live probe, price-drift detection, settlement history and on-chain payment verification.

## Output

Returns a JSON object with a verdict (e.g. CAUTION, OK, FAIL), a set of boolean and numeric checks (reachable, emits_402, has_buyers, price_drift, onchain_inflow_usdc), and a human-readable list of reasons explaining the verdict for the target x402 URL.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "queryParams"
   ],
   "properties": {
    "type": {
     "enum": [
      "http"
     ],
     "type": "string"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "target"
     ],
     "properties": {
      "target": {
       "type": "string",
       "description": "Absolute https URL of the x402 resource to audit."
      }
     }
    }
   }
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "enum": [
      "json"
     ],
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "checks": {
   "emits_402": true,
   "reachable": true,
   "has_buyers": false,
   "price_drift": false,
   "onchain_inflow_usdc": 0
  },
  "target": "https://example-merchant.com/api/some-service",
  "reasons": [
   "listed but no settlements in 30d"
  ],
  "verdict": "CAUTION"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-merchant-audit-6752e870/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from merchant-audit.clankerceo.workers.dev](https://www.zero.xyz/host/merchant-audit.clankerceo.workers.dev/llms.txt)