# DNS CNAME Lookup for app.<domain> Subdomain via Cloudflare DoH

> DNS CNAME Lookup for app.<domain> Subdomain via Cloudflare DoH is a paid API for AI agents from dns.intel.rallylive.ca, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-21).

Looks up the CNAME record of the app.<domain> subdomain using Cloudflare DNS over HTTPS and returns existence status, records, and TTL.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/dns/host/app/cname?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/dns-cname-lookup-for-app-domain-subdomain-via-cloudflare-doh-ef1da214
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_XalUpZVViYACfYdN3FpS7

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 dns-cname-lookup-for-app-domain-subdomain-via-cloudflare-doh-ef1da214
```

Example prompt: Can you check whether app.acmecorp.com has a CNAME record configured — I want to know if the app subdomain exists and what it points to, using Cloudflare DNS?

## When to prefer this

Choose this endpoint when you need a fast, targeted check on whether the app.<domain> subdomain has a CNAME record, without performing a full subdomain enumeration. Ideal when you already know the parent domain and want a quick existence and target check for the canonical 'app' host pattern using Cloudflare's trusted DoH infrastructure.

## Known failure modes

- Domain does not exist — NXDOMAIN response with no records
- app subdomain has no CNAME record (may have A/AAAA instead) — empty or negative response
- Invalid or malformed domain input — error or unexpected response
- Cloudflare DoH resolver unreachable — service timeout or error
- Rate limiting or payment failure — request rejected

## How this service works

CNAME record of app.<domain>: looks up the app host under the domain you give (CNAME via Cloudflare DoH) and reports whether it exists, its records and TTL. Quick existence check for common hosts like app without enumerating subdomains. $0.01 per lookup.

## Output

Returns whether the CNAME record for app.<domain> exists, the CNAME target record data, the TTL value, and the DNS response code from Cloudflare's DoH resolver.

## 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",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/dns-cname-lookup-for-app-domain-subdomain-via-cloudflare-doh-ef1da214/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from dns.intel.rallylive.ca](https://www.zero.xyz/host/dns.intel.rallylive.ca/llms.txt)