# dns-txt-app-subdomain

> dns-txt-app-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 TXT DNS record for the 'app' subdomain of a given domain using Cloudflare DoH and reports existence, records, and TTL.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/dns/host/app/txt?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-txt-app-subdomain-7d200845
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_O9p_mEVjLQLMwZUja7ems

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-app-subdomain-7d200845
```

Example prompt: Can you check if there's a TXT record set on the app subdomain of example.com — I want to know if it exists and what its value and TTL are?

## When to prefer this

Use this endpoint when you specifically need to check TXT records for the 'app' subdomain of a domain quickly without enumerating all subdomains. Prefer this over generic DNS lookup tools when you know you want the 'app' host and TXT record type specifically, and want Cloudflare DoH resolution with TTL info included.

## Known failure modes

- Domain not found or invalid domain name provided — returns non-existence or DNS error
- Cloudflare DoH upstream timeout or outage — lookup may fail or return stale data
- app subdomain has no TXT record — returns empty record set with existence=false
- Malformed domain input may result in an error response

## How this service works

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

## Output

Returns whether the TXT record for app.<domain> exists, the record values (if present), and the TTL as resolved by Cloudflare DNS over HTTPS. Indicates non-existence if no record is found.

## 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-app-subdomain-7d200845/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)