# DNS AAAA Record Lookup for smtp Subdomain

> DNS AAAA Record Lookup for smtp 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 2026-10-21).

Looks up the IPv6 (AAAA) DNS record for the smtp.<domain> host via Cloudflare DNS-over-HTTPS and returns whether it exists, its records, and TTL.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/dns/host/smtp/aaaa?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-aaaa-record-lookup-for-smtp-subdomain-55916966
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_SN129FeK97Hcuq5DWvzaC

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-aaaa-record-lookup-for-smtp-subdomain-55916966
```

Example prompt: Can you check whether smtp.example.com has an IPv6 (AAAA) DNS record — I want to know if it exists and what its TTL is?

## When to prefer this

Use this endpoint when you specifically need to check whether the smtp subdomain of a given domain has an IPv6 (AAAA) DNS record, without performing broad subdomain enumeration. Ideal for quick existence checks on mail server IPv6 configuration. Prefer over general DNS tools when you want a targeted, per-domain, pay-per-lookup approach via Cloudflare DoH.

## Known failure modes

- Domain does not have an smtp subdomain — returns NXDOMAIN with no records
- Invalid or malformed domain name causes a failed lookup
- Cloudflare DoH upstream unavailability leads to timeout or error response
- Domain exists but smtp host has no AAAA record (only A record) — returns empty record set

## How this service works

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

## Output

Returns whether the smtp.<domain> AAAA record exists, the IPv6 address(es) in the record, the TTL, and the DNS response code (e.g. NOERROR or NXDOMAIN), as resolved 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-aaaa-record-lookup-for-smtp-subdomain-55916966/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)