# DKIM Selector SMTP Watch

> DKIM Selector SMTP 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 public key record for the 'smtp' selector of a domain and alerts when it changes, comparing against the previously cached result.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/watch/dns/dkim/smtp?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-smtp-watch-339c2da5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_kJEFN__b7AmY2qK9RadoG

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-smtp-watch-339c2da5
```

Example prompt: Keep an eye on the smtp DKIM selector record for example.com and let me know if anything changes — compare it against the last known value and tell me exactly what fields are different.

## When to prefer this

Use this endpoint when you need to continuously monitor the smtp DKIM selector specifically (not other selectors) for a domain, and want change-detection with delta reporting rather than a raw DNS lookup. It is ideal for scheduled polling workflows where you care about drift, key rotation, or unauthorized modifications to the smtp DKIM record over time. Prefer it over a plain DKIM lookup endpoint when you need the 'changed' flag and before/after field comparison baked in.

## Known failure modes

- Domain does not exist or has no smtp DKIM record — returns current empty/null result with changed flag reflecting any prior state
- No previous check exists for the domain — changed may be null or false with no before values
- DNS lookup failure or timeout — may return an error or partial result
- Domain input missing or malformed — request may fail validation

## How this service works

Change watch for dkim selector smtp: 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 TXT record for smtp._domainkey.<domain>, a boolean 'changed' flag, a list of fields that changed with before/after values, and the timestamp of when the record was last seen. The previous result is retained for 90 days for comparison.

## 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-smtp-watch-339c2da5/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)