# DNS CNAME Lookup for sip Subdomain

> DNS CNAME Lookup for sip 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 CNAME record for the sip.<domain> subdomain via Cloudflare DNS-over-HTTPS and returns whether it exists, its records, and TTL.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/dns/host/sip/cname?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-cname-lookup-for-sip-subdomain-4b63abb5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1SbGSk63H1QHbVHc0WIIg

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-sip-subdomain-4b63abb5
```

Example prompt: Can you check if example.com has a CNAME record configured for its sip subdomain — I want to know if the sip.example.com host exists and what it points to.

## When to prefer this

Use this endpoint when you need a quick, targeted check on whether the sip subdomain of a specific domain has a CNAME record configured — without needing to enumerate all subdomains or query multiple DNS record types. Ideal for VoIP/SIP infrastructure validation, DNS auditing, or pre-deployment checks for SIP services.

## Known failure modes

- Domain not found or no CNAME record at sip.<domain> returns a NXDOMAIN or empty response
- Malformed domain input may result in an error or unexpected DNS response
- Cloudflare DoH upstream unavailability could cause lookup failures
- Rate limits or payment failures may prevent access

## How this service works

CNAME record of sip.<domain>: looks up the sip 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 sip without enumerating subdomains. $0.01 per lookup.

## Output

Returns whether the sip.<domain> CNAME record exists, the CNAME target it resolves to, the TTL value, and the DNS response code — all answered 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-cname-lookup-for-sip-subdomain-4b63abb5/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)