# dns-txt-mx1-subdomain

> dns-txt-mx1-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 TXT records for the mx1 subdomain of a given domain via Cloudflare DNS over HTTPS, reporting existence, record values, and TTL.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/dns/host/mx1/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-mx1-subdomain-ca5fde50
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TkcCSuWSFmb4zXKPzLHY4

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-mx1-subdomain-ca5fde50
```

Example prompt: Can you check if mx1.example.com has any TXT records in DNS — I want to know if it exists and what records and TTL it returns?

## When to prefer this

Use this endpoint when you need a quick, targeted check of TXT records specifically on the mx1 subdomain of a domain — for example to verify mail server configuration, SPF records, or subdomain existence — without needing to enumerate all subdomains. Prefer this over generic DNS lookup tools when you specifically care about the mx1 host and want Cloudflare's resolver perspective.

## Known failure modes

- Domain does not exist — returns NXDOMAIN with no records
- mx1 subdomain has no TXT records — returns NOERROR with empty record set
- Invalid or malformed domain input — may return error or unexpected response
- Cloudflare DoH service unavailable — upstream timeout or error
- Network failure reaching the endpoint — HTTP error returned

## How this service works

TXT record of mx1.<domain>: looks up the mx1 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 mx1 without enumerating subdomains. $0.01 per lookup.

## Output

Returns whether the mx1.<domain> host exists in DNS, its TXT record values (e.g. SPF, verification strings), TTL in seconds, 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-txt-mx1-subdomain-ca5fde50/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)