# Revenue Swarm x402 Audit — x402 Payment Compatibility Checker

> Revenue Swarm x402 Audit — x402 Payment Compatibility Checker is a paid API for AI agents from eu-tender-x402-v3-production.up.railway.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-29).

Audits a public x402 endpoint for payment protocol compatibility, returning a score, pass/fail checks, warnings, and hard failures.

## Facts

- Endpoint: GET https://eu-tender-x402-v3-production.up.railway.app/api/x402-audit?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/revenue-swarm-x402-audit-x402-payment-compatibility-checker-1b982516
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_SJF3M92v4XnC-tzCWpl9j

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 revenue-swarm-x402-audit-x402-payment-compatibility-checker-1b982516
```

Example prompt: Can you audit this x402 endpoint for payment protocol compatibility and give me a score, verdict, and any warnings or hard failures? The URL to check is https://my-api.example.com/api/my-paid-endpoint.

## When to prefer this

Use this endpoint when you need to verify that a specific public URL correctly implements the x402 HTTP payment protocol before integrating it, listing it on a facilitator, or including it in an agent workflow. It is the right choice for pre-flight compatibility checking and diagnosing payment flow issues on x402 APIs, rather than for general API health checks or non-x402 payment systems.

## Known failure modes

- Missing or invalid 'url' query parameter returns an error
- Target URL is unreachable or returns no x402 headers — audit may return hard failures or incomplete checks
- Non-public or firewalled endpoints may produce incomplete audit results
- Malformed URL input may cause validation errors
- Network timeout on the target endpoint may cause partial results

## How this service works

Pay-per-call B2B sales lead and procurement intelligence plus Base wallet data for agents. Search EU tenders/RFPs or inspect a Base wallet. Payments use x402 USDC on Base.

## Output

Returns a JSON object containing a numeric compatibility score (0–100), an overall verdict string (e.g. 'compatible'), an array of individual check results, a list of warnings, a list of hard failures, the target URL audited, the product label, and a generated_at timestamp.

## 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"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "description": "Public x402 endpoint to audit"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "score": {
       "type": "integer"
      },
      "checks": {
       "type": "array",
       "items": {
        "type": "object"
       }
      },
      "target": {
       "type": "string"
      },
      "product": {
       "type": "string"
      },
      "verdict": {
       "type": "string"
      },
      "warnings": {
       "type": "array",
       "items": {
        "type": "string"
       }
      },
      "generated_at": {
       "type": "string"
      },
      "hard_failures": {
       "type": "array",
       "items": {
        "type": "string"
       }
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "score": 100,
  "checks": [],
  "product": "x402 Payment Preflight & Settle Check",
  "verdict": "compatible",
  "warnings": [],
  "hard_failures": []
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/revenue-swarm-x402-audit-x402-payment-compatibility-checker-1b982516/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from eu-tender-x402-v3-production.up.railway.app](https://www.zero.xyz/host/eu-tender-x402-v3-production.up.railway.app/llms.txt)