MX Lookup Skill

Overview

Pass any domain name to run a live DNS lookup for its mail configuration. The response returns the queried domain and an array of MX entries, showing each mail exchange server hostname paired with its priority routing integer.

Live Test MX Lookup Skill Skill →

The tool

Once your client is connected to the VerveKit server, this appears in its tool list as MXLookupSkill. It is read-only and open-world — it fetches and never mutates anything on your side — so most clients call it without asking you to confirm.

{
  "name": "MXLookupSkill",
  "arguments": {
    "domain": "yahoo.com"
  }
}

You do not name the tool yourself; the model picks it. Asking about yahoo.com in the terms this skill covers is enough for it to reach for MXLookupSkill on its own — naming it explicitly also works, and is the way to force the call.

Connecting

One server URL covers every skill in the catalog, including this one. Authorization is OAuth: the client opens a browser once, and there is no key to paste into a config file.

{
  "mcpServers": {
    "vervekit": {
      "url": "https://api.vervekit.com/v1/mcp"
    }
  }
}

https://api.vervekit.com/v1/mcp

Per-client setup — Claude, Cursor, VS Code, ChatGPT — is on the MCP setup page.

Arguments

These are the properties on the tool's inputSchema, so a well-behaved client validates them before the call is made. Premium arguments are accepted on every plan but only take effect on plans that include them.

What the model gets back

The result carries a structuredContent object matching the tool's declared outputSchema, so a client reads fields without parsing prose. status is "ok" and error is null on success; a null field means the value was not available for that input, not that the call failed.

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{
  "status": "ok",
  "error": null,
  "data": {
    "domain": "yahoo.com",
    "mx": [
      {
        "priority": 1,
        "exchange": "mta7.am0.yahoodns.net"
      },
      {
        "priority": 1,
        "exchange": "mta6.am0.yahoodns.net"
      },
      {
        "priority": 1,
        "exchange": "mta5.am0.yahoodns.net"
      }
    ]
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Failure modes

Errors come back as tool errors carrying a sentence the model can act on, not a bare status code. Error handling covers the full list.

A call costs 10 credits each time the tool actually runs; a model that reasons about the tool without calling it costs nothing.

Use cases

Signup Email Validation

To stop fake signups, authentication workflows check MX records to confirm the registrant's email domain can actually accept incoming messages.

Domain Migration Auditing

DevOps engineers track exchange hostnames and priority numbers before and after DNS changes to verify mail traffic directs to new servers.

Cold Outreach Deliverability

Sales outreach software verifies that recipient domains have active mail servers before scheduling outbound campaign sequences to protect sender reputation.

Mail Provider Detection

Identify whether a prospect uses Google Workspace, Microsoft 365, or self-hosted infrastructure by parsing the returned exchange server hostnames.

Other ways to use MX Lookup Skill

Set up MX Lookup Skill on VerveKit, or reach the same source a different way. Your VerveKit account and credits work on all of them — one key, one balance.

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