# Revenue Swarm x402 Payment Preflight & Audit

> Revenue Swarm x402 Payment Preflight & Audit is a paid API for AI agents from eu-tender-x402-v2-production.up.railway.app, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-02).

Validates x402 USDC payment compatibility for a Base wallet or endpoint before committing a pay-per-call transaction

## Facts

- Endpoint: GET https://eu-tender-x402-v2-production.up.railway.app/api/x402-audit?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/revenue-swarm-x402-payment-preflight-audit-86006455
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_NqtxOhQ0RFlNPUpw_K_27

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-payment-preflight-audit-86006455
```

Example prompt: Run an x402 payment preflight audit to check if my Base wallet is compatible and ready to make USDC pay-per-call API calls — I need to see the score, verdict, and any hard failures before I proceed.

## When to prefer this

Use this endpoint when you need to verify x402 USDC payment compatibility on Base before executing pay-per-call API calls, especially when onboarding a new agent wallet or debugging payment failures. Prefer this over simply attempting a live call when you want to avoid spending USDC on a transaction that will fail, or when you need a structured audit report with scores and hard-failure diagnostics.

## Known failure modes

- Wallet address not provided or malformed — returns error or low score
- x402 payment parameters missing or incompatible — reflected as hard_failures in response
- Network issues reaching Base — connection timeout
- USDC balance insufficient for preflight — flagged in warnings
- Railway app cold start causing slow initial response

## 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 with a numeric compatibility score (0-100), a verdict string ('compatible' or otherwise), an array of checks performed, a list of warnings, and a list of hard failures — letting the caller know whether the x402 payment flow is ready to proceed.

## 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-payment-preflight-audit-86006455/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from eu-tender-x402-v2-production.up.railway.app](https://www.zero.xyz/host/eu-tender-x402-v2-production.up.railway.app/llms.txt)