# dns-txt-sip-subdomain

> dns-txt-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 TXT DNS record for the sip.<domain> subdomain via Cloudflare DoH and reports its existence, record values, and TTL.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/dns/host/sip/txt?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-txt-sip-subdomain-167fed37
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_mZpGHWVDupWqa6ygS1G8E

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-txt-sip-subdomain-167fed37
```

Example prompt: Can you check if sip.example.com has any TXT DNS records and tell me what they say and how long until they expire?

## When to prefer this

Use this endpoint when you specifically need to check the TXT DNS record for the sip.<domain> subdomain (commonly used for VoIP/SIP service configuration) without enumerating all subdomains. Prefer it over general DNS lookup tools when you want a quick, targeted existence check for the sip host with TTL information, and when you're operating in an x402 micropayment-capable environment at low cost ($0.01 per call).

## Known failure modes

- Domain does not exist — returns not found or empty result
- sip subdomain has no TXT records — existence reported as false with empty records
- Malformed or missing domain input — request may fail or return an error
- Cloudflare DoH upstream timeout — service may return an error or delayed response
- Rate limiting or payment failure — 402 payment required if x402 credentials are missing

## How this service works

TXT record of sip.<domain>: looks up the sip host under the domain you give (TXT 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> subdomain has TXT DNS records, along with the record values (strings) and TTL in seconds, queried 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-txt-sip-subdomain-167fed37/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)