Listing Guard

Check public x402 discovery metadata with an unpaid CDP technical validation and inspect heuristic listing-risk flags and suggested rewrites.

Know the limits

Heuristics can flag legitimate wording. A low score is not safety or policy certification. CDP validation does not promise Bazaar indexing or paid delivery.

A 30-second integration

Examples use placeholders. Plain requests to paid tools return a payment challenge, not a paid result. Free Lint can perform an unpaid public probe. Inspect the response status and evidence scope before using any result.

curl

curl -i https://api.spendpreflight.com/listing-guard \
  -H 'Content-Type: application/json' \
  -d '{"url":"https://api.example.com/data","method":"GET"}'

MCP

Connect to https://api.spendpreflight.com/mcp. Call the existing tool:

{
  "name": "listing_guard",
  "arguments": {
    "url": "https://api.example.com/data",
    "method": "GET"
  }
}

SDK / JavaScript

Use standard fetch alongside the SpendPreflight SDK; the example does not invent a dedicated exported method.

// Node.js SDK integration: use your explicitly budgeted fetch.
// Plain fetch below never signs or pays. There is no dedicated
// spendpreflight SDK helper for this operation.
const response = await fetch('https://api.spendpreflight.com/listing-guard', {
  method: 'POST', headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({"url":"https://api.example.com/data","method":"GET"})
});
console.log(response.status, await response.text());

Frequently asked questions

Related tools

Payee Screening · Seller Monitoring · Token Safety

Authoritative OpenAPI schemas · What this service stores · Practical guides