Domain Deliverability Checker MCP Server

An MCP server that exposes the Mamba Labs Domain Deliverability Checker as a single tool. Install one package and give your MCP client a way to audit any domain's email deliverability and DNS health, wrapping the Mamba Labs actor on Apify and returning Clay-ready flat JSON.

What's Inside

• What it does

• Quick start

• Prerequisites

• Example prompts

• Tool and inputs

• Output

• Pricing

• Full actor documentation

• Mamba Labs GTM Suite

• License

Related MCP server: mcp-job-board-keyword-signal-scanner

What it does

This server gives an AI client one tool:

• check_domain_deliverability: audit one domain or a list of domains for SPF, DKIM, DMARC, MX, mail provider, DNS blacklist status, catch-all, domain age, and a 0 to 100 deliverability score. Results are cached for 24 hours per domain. It reads public DNS only, sends no email, and does not verify individual mailboxes.

All of the work runs on Apify. This package is a thin client that routes the tool call to the actor and hands back the result.

Quick start

You need Node.js 18 or newer and an Apify account with an API token.

Add this to your Claude Desktop config:

{
  "mcpServers": {
    "mamba-domain-deliverability-checker": {
      "command": "npx",
      "args": ["-y", "@mambalabsdev/mcp-domain-deliverability-checker"],
      "env": {
        "APIFY_TOKEN": "your-apify-token"
      }
    }
  }
}

Get your token at https://console.apify.com/account/integrations, paste it in, and restart Claude Desktop. The tool will be available.

Prerequisites

• Node.js 18 or newer

• An Apify account with an API token

Example prompts

• "Check the email deliverability of stripe.com."

• "Does github.com have SPF, DKIM, and DMARC set up, and what is its DMARC policy?"

• "Audit these domains for deliverability: stripe.com, notion.so, figma.com."

• "Is acme.com on any DNS blacklist, and what is its mail provider?"

Tool and inputs

check_domain_deliverability:

• domain (string): bare domain to audit, e.g. stripe.com. Provide this or domains.

• domains (array): list of bare domains for batch processing. Takes precedence over domain.

• batchSize (integer): how many domains from the list are audited at the same time. 1 to 10. Default 5.

• skipCache (boolean): ignore the 24 hour result cache and audit again now, for example right after a DNS change. Default false.

• attempt_catch_all (boolean): run the SMTP catch-all probe. Off by default; the Apify platform blocks port 25, so it returns unknown there.

Output

One flat row per domain: domain, spf_record, spf_valid, spf_policy, dkim_selectors_found, dkim_present, dmarc_record, dmarc_policy, dmarc_valid, mx_records, has_mx, mail_provider, catch_all, catch_all_status, blacklisted, blacklists_listed, blacklists_checked, blacklist_status, spam_trap_risk, spam_trap_flags, domain_age_days, domain_age_source, has_website, deliverability_score, risk_level, audit_error, and run_date.

Pricing

Domain Deliverability Checker is pay per event on Apify.

The tool starts the actor run and polls it to a finished status, so a long run is not cut off at 300 seconds. A run that does not succeed comes back as an error with its run ID and status.

Full actor documentation

For the complete input and output reference, pricing, and run history, see the Domain Deliverability Checker actor on the Apify Store:

https://apify.com/mambalabs/domain-deliverability-checker

The wrapper calls the actor by its immutable ID 0tVgxI7A6o9jMlxmc, so a Store rename never breaks it.

Mamba Labs GTM Suite

This server is part of the Mamba Labs GTM Suite, a fleet of twelve specialized MCP servers for go-to-market signal intelligence, each backed by a dedicated Apify actor.

Built by Mamba Labs | npm | Apify Store

License

MIT

Built by Mamba Labs. https://apify.com/mambalabs