# Reverse DNS via Google Change Watch

> Reverse DNS via Google Change Watch is a paid API for AI agents from ip.intel.rallylive.ca, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-11).

Monitors reverse DNS (PTR record) lookups via Google for a given IP, returning the current result, whether it changed, and a before/after diff compared to the previous call.

## Facts

- Endpoint: GET https://ip.intel.rallylive.ca/watch/ip/ptr/via/google?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/reverse-dns-via-google-change-watch-56a4e696
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_D2lcB0KULyGebGnbtFESR

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 reverse-dns-via-google-change-watch-56a4e696
```

Example prompt: Keep an eye on the reverse DNS record for 8.8.8.8 using Google and tell me if it has changed since last time — I want to know the old and new hostname if it flipped.

## When to prefer this

Choose this endpoint when you need to detect changes in reverse DNS (PTR records) for a specific IP over time, especially for scheduled polling or alerting workflows. It is distinct from a one-off PTR lookup because it stores prior state and surfaces diffs automatically. Prefer it for security monitoring, ISP/IP ownership tracking, or infrastructure drift detection where knowing 'did this change?' matters more than just knowing the current value.

## Known failure modes

- IP has no PTR record — returns empty or null hostname
- First call for an IP returns no comparison baseline (no prior stored result)
- Stored result has expired (older than 90 days) — treated as first call
- Google DNS unavailable — lookup fails with error
- Invalid or malformed IP address input — request rejected
- Payment failure prevents check from being executed

## How this service works

Change watch for reverse dns via google: runs the check, compares it with the result from your previous call for the same ip (kept 90 days) and returns the current answer, changed true/false, the fields that changed with before/after values, and when it was last seen. Schedule it to be alerted when this changes. $0.02 per check.

## Output

Returns the current PTR record hostname resolved via Google DNS, a boolean 'changed' flag indicating if the result differs from the previous call for that IP (stored up to 90 days), a diff of fields that changed including before and after values, and the timestamp of when the IP was last seen.

## 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/reverse-dns-via-google-change-watch-56a4e696/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ip.intel.rallylive.ca](https://www.zero.xyz/host/ip.intel.rallylive.ca/llms.txt)