# Lookproof DNS Wildcard Detector

> Lookproof DNS Wildcard Detector is a paid API for AI agents from api.lookproof.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-31).

Checks whether a DNS zone has a wildcard record (RFC 4592) by querying A, AAAA, TXT, and MX types for a random uncached subdomain, with a warning if wildcard MX accepts mail for invented subdomains.

## Facts

- Endpoint: GET https://api.lookproof.dev/v1/dns/wildcard?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/lookproof-dns-wildcard-detector-e3c0e356
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_x4uzRgr1vnQPGoJLbcDFh

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 lookproof-dns-wildcard-detector-e3c0e356
```

Example prompt: Can you check if example.com has a DNS wildcard — specifically whether any random subdomain resolves due to a wildcard A, AAAA, TXT, or MX record, and warn me if there's a wildcard MX that would accept mail for made-up subdomains?

## When to prefer this

Choose this endpoint when you need to definitively determine whether a subdomain truly exists in DNS or is simply matched by a zone-wide wildcard record. It is especially useful for security audits, subdomain enumeration validation, and email infrastructure checks. Prefer it over a plain DNS resolver when wildcard-awareness is required — a standard resolve would return results for invented subdomains without flagging that a wildcard is responsible.

## Known failure modes

- Invalid or malformed domain name returns a 4xx error
- Domain does not exist in DNS (NXDOMAIN) may return an indeterminate or error result
- Public resolver timeouts may cause lookup failures
- Very long domain names exceeding 1024 characters are rejected
- Domains with aggressive rate limiting on public resolvers may produce incomplete results

## How this service works

Check SPF, DMARC, DKIM, MTA-STS, DNSSEC and more, with results that explain what was found and why. Free browser checks and a pay-per-request API with x402.

## Output

Returns whether the DNS zone has wildcard records for A, AAAA, TXT, and MX record types, determined by querying a random uncached subdomain through public resolvers. Includes a specific warning if a wildcard MX record is detected, meaning the domain would accept mail for any invented subdomain.

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "title": "DomainInput",
     "required": [
      "domain"
     ],
     "properties": {
      "domain": {
       "type": "string",
       "title": "Domain",
       "examples": [
        "example.com"
       ],
       "maxLength": 1024,
       "minLength": 1
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/lookproof-dns-wildcard-detector-e3c0e356/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.lookproof.dev](https://www.zero.xyz/host/api.lookproof.dev/llms.txt)