# DKIM Selector HS2 Change Watch

> DKIM Selector HS2 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 'hs2' DNS record for a domain and returns whether it has changed since the last check, along with before/after field diffs.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/watch/dns/dkim/hs2?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-hs2-change-watch-901b9863
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZRDecn_3monT9BqMW7P1g

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-hs2-change-watch-901b9863
```

Example prompt: Keep an eye on the DKIM hs2 selector for example.com and let me know if anything has changed since the last time you checked — show me what fields changed and what the values were before and after.

## When to prefer this

Use this endpoint when you need to detect changes specifically in the DKIM hs2 selector record for a domain over time. It is ideal for automated monitoring pipelines, security audits, or email deliverability workflows where you want to be alerted to key rotations or unexpected record modifications. Prefer this over a plain DKIM lookup endpoint when change detection and diffing (before/after field comparison) is the primary goal.

## Known failure modes

- Domain has no DKIM hs2 selector record — returns current answer with empty/NXDOMAIN result
- First-time call for a domain has no prior snapshot to compare against — changed will be false or indeterminate
- Domain lookup fails due to DNS resolution errors
- Stored snapshot is older than 90 days and has been purged, treating the call as a first-time check
- Payment not authorized — request rejected before check is run

## How this service works

Change watch for dkim selector hs2: 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 DKIM hs2 selector record, a boolean 'changed' flag indicating if it differs from the previous check (stored up to 90 days), a list of fields that changed with before/after values, and the 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-hs2-change-watch-901b9863/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)