MX Record Grounding Data

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 Record Grounding Data Source →

The tool

Once your client is connected to the VerveContext server, this appears in its tool list as MXRecordGroundingData. 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": "MXRecordGroundingData",
  "arguments": {
    "domain": "yahoo.com"
  }
}

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

Connecting

One server URL covers every source 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": {
    "vervecontext": {
      "url": "https://api.vervecontext.com/v1/mcp"
    }
  }
}

https://api.vervecontext.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.

Why ground on it

A model can produce something that looks like this answer from its training data, and be confidently out of date or simply wrong. This source returns the current value in a shape you can check, which is the difference between an answer you can cite and one you have to hedge.

Point an evaluation at mx.0.priority: it is the field most worth pinning a claim to, and it is either present and current or absent — never plausibly invented.

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 Record Grounding Data

Set up MX Record Grounding Data on VerveContext, or reach the same source a different way. Your VerveContext account and credits work on all of them — one key, one balance.

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