# DKIM Selector Postmark Change Watch

> DKIM Selector Postmark Change Watch is a paid API for AI agents from dns.intel.rallylive.ca, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-20).

Monitors the DKIM selector for Postmark on a domain and returns whether it has changed since the last check, with before/after field diffs.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/watch/dns/dkim/postmark?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/dkim-selector-postmark-change-watch-4860470f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_moVpH4KP0cUA2V7Ehprbc

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 dkim-selector-postmark-change-watch-4860470f
```

Example prompt: Keep an eye on the Postmark DKIM selector for example.com and let me know if it changes — I want to see what the old and new values were and when it last changed.

## When to prefer this

Choose this endpoint when you need to detect and be alerted to changes in a domain's Postmark DKIM selector over time, particularly for scheduled monitoring or auditing email authentication configuration drift. It is specifically designed for Postmark's DKIM selector (not generic DKIM or other ESPs) and provides diff-aware change detection rather than just a raw DNS lookup.

## Known failure modes

- Domain not found or has no Postmark DKIM selector — returns current answer with no previous comparison data
- No previous check exists within 90-day window — changed flag may be null or false with no diff
- Domain parameter missing or malformed — returns validation error
- DNS lookup failure for the domain — returns error with no result
- Network timeout reaching DNS resolver — returns error

## How this service works

Change watch for dkim selector postmark: runs the check, compares it with the result from your previous call for the same domain (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 Postmark DKIM selector value for the domain, a boolean 'changed' flag indicating whether it differs from the previous check (stored up to 90 days), a list of changed fields with before/after values, and a timestamp of when the record 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/dkim-selector-postmark-change-watch-4860470f/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)