# dns-a-demo-subdomain

> dns-a-demo-subdomain is a paid API for AI agents from dns.intel.rallylive.ca, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-20).

Looks up the A record for the 'demo' subdomain of a given domain via Cloudflare DoH and reports its existence, IP addresses, and TTL.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/dns/host/demo/a?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/dns-a-demo-subdomain-c73d7a32
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_te0O5UadBl0sOCWDwh2Yg

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-a-demo-subdomain-c73d7a32
```

Example prompt: Can you check if demo.acmecorp.com has an A record — I want to know its IP address and TTL, and whether it actually exists in DNS?

## When to prefer this

Use this endpoint when you need a quick, cheap ($0.01) existence and resolution check specifically for the 'demo' subdomain of a domain, without enumerating all subdomains. Ideal for pre-launch checks, monitoring whether a demo environment is DNS-live, or auditing whether a specific domain exposes a demo host. Prefer this over generic DNS tools when you want a focused single-host check with built-in Cloudflare DoH reliability.

## Known failure modes

- Domain does not exist (NXDOMAIN) — returns non-existence result
- demo subdomain has no A record but domain itself exists — returns empty/not-found
- Network timeout reaching Cloudflare DoH — may return error
- Invalid or malformed domain input — may return error or unexpected result
- SERVFAIL from upstream DNS — returns error response

## How this service works

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

## Output

Returns whether the 'demo' subdomain A record exists for the given domain, along with the resolved IPv4 address(es) and the DNS TTL value. If the record does not exist, reports non-existence. Data is fetched fresh via Cloudflare DNS over HTTPS.

## 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-a-demo-subdomain-c73d7a32/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)