# x402 Validator — x402 Endpoint Conformance Auditor

> x402 Validator — x402 Endpoint Conformance Auditor is a paid API for AI agents from x402-validator-tools.fly.dev, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-12).

Audits a target URL for strict x402 protocol conformance, live 402 payment-gate behavior, and operator-actionable compliance evidence before an agent spends funds.

## Facts

- Endpoint: POST https://x402-validator-tools.fly.dev/validate?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-validator-x402-endpoint-conformance-auditor-235c60b6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_wJeRUm-U2dFsTTVpDREsO

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-validator-x402-endpoint-conformance-auditor-235c60b6 -d '<json body>'
```

Example prompt: Before I integrate that payment-gated endpoint at https://api.example.com/data, can you run an x402 conformance audit on it in standard mode and give me a plain-language summary of any issues?

## When to prefer this

Use this endpoint when an AI agent or developer needs to verify that a specific x402 payment-gated URL is correctly implemented before committing funds or integrating it into a workflow. It is the right choice when you need strict-v2 protocol conformance evidence, per-check diagnostics, and optionally AI-generated fix guidance — rather than just a simple HTTP reachability probe or a generic API health check.

## Known failure modes

- Target URL is unreachable or times out — check result will show connection failure
- Target does not return a 402 status at all — fails live 402 behavior check
- Missing or malformed x402 payment headers — specific checks flagged with details
- advise or explain fields require INCEPTION_API_KEY to be configured server-side — omitting key returns null for those fields
- Invalid or non-HTTP URL provided — request rejected with validation error
- Marketplace mode applied to a non-marketplace endpoint — may produce irrelevant check results

## How this service works

Verify x402 endpoints with strict-v2 conformance, live 402 behavior, and operator-actionable evidence before agents spend. Built by Gael Leonardo Chulim Gongora (mss_ali / Ali Nain).

## Output

Returns a structured audit report containing an overall pass/fail/warn status, a human-readable summary, an array of named per-check results (each with status, message, and optional details), latency in milliseconds, a timestamp, and optionally an AI-generated remediation advice string and/or plain-language explanation of the findings.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "url"
 ],
 "properties": {
  "url": {
   "type": "string",
   "description": "Target merchant URL to audit (http or https)"
  },
  "mode": {
   "enum": [
    "standard",
    "marketplace"
   ],
   "type": "string",
   "description": "standard | marketplace"
  },
  "advise": {
   "type": "boolean",
   "description": "Attach Inception AI remediation advice (requires INCEPTION_API_KEY server-side)"
  },
  "explain": {
   "type": "boolean",
   "description": "Attach a plain-language AI summary of the result for non-experts (requires INCEPTION_API_KEY server-side)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "title": "ValidateResponse",
 "required": [
  "url",
  "overall",
  "summary",
  "checks",
  "timestamp"
 ],
 "properties": {
  "url": {
   "type": "string",
   "title": "Url"
  },
  "checks": {
   "type": "array",
   "items": {
    "type": "object",
    "title": "CheckResultItem",
    "required": [
     "name",
     "status",
     "message"
    ],
    "properties": {
     "name": {
      "type": "string",
      "title": "Name"
     },
     "status": {
      "type": "string",
      "title": "Status"
     },
     "details": {
      "anyOf": [
       {
        "type": "object",
        "additionalProperties": true
       },
       {
        "type": "null"
       }
      ],
      "title": "Details"
     },
     "message": {
      "type": "string",
      "title": "Message"
     }
    },
    "description": "One check result, flattened for JSON consumers."
   },
   "title": "Checks"
  },
  "overall": {
   "type": "string",
   "title": "Overall"
  },
  "summary": {
   "type": "string",
   "title": "Summary"
  },
  "ai_advice": {
   "anyOf": [
    {
     "type": "string"
    },
    {
     "type": "null"
    }
   ],
   "title": "Ai Advice"
  },
  "timestamp": {
   "type": "string",
   "title": "Timestamp"
  },
  "ai_summary": {
   "anyOf": [
    {
     "type": "string"
    },
    {
     "type": "null"
    }
   ],
   "title": "Ai Summary"
  },
  "latency_ms": {
   "anyOf": [
    {
     "type": "number"
    },
    {
     "type": "null"
    }
   ],
   "title": "Latency Ms"
  }
 },
 "description": "Audit response."
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-validator-x402-endpoint-conformance-auditor-235c60b6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-validator-tools.fly.dev](https://www.zero.xyz/host/x402-validator-tools.fly.dev/llms.txt)