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 it does

This server gives an AI client one tool:

• check_domain_deliverability: audit a domain's SPF, DKIM, DMARC, MX, mail provider, DNS blacklist status, catch-all, domain age, and a 0 to 100 deliverability score.

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.

Related MCP server: nslookup.io MCP Server

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 (number): domains audited concurrently per wave in batch mode. Default 5, maximum 10.

• skipCache (boolean): force a fresh audit and ignore the 24 hour result cache.

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

Full actor documentation

For the complete input and output reference, pricing, and run history, see the Domain Deliverability Checker actor on the Apify Store (canonical immutable Actor ID URL):

https://apify.com/mambalabs/0tVgxI7A6o9jMlxmc

License

MIT

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