English Français العربية

Mail7 Email Validation

Official registry Productivity

Verify email addresses, clean lists, and audit a domain SPF, DKIM, DMARC and MX setup.

Source code Website Documentation

What can you do with Mail7 Email Validation?

  • "Is sales@acme.com a real mailbox?"
  • "Clean this list of signups and tell me which ones bounce."
  • "Why do our emails to customers land in spam? Check ourdomain.com."

Install

Add this to your client's MCP configuration (Claude Desktop: claude_desktop_config.json; Cursor: .cursor/mcp.json; VS Code and others use the same "mcpServers" shape).

NPM package mail7-mcp
Claude Code 
claude mcp add mail7-email-validation -e 'MAIL7_API_KEY=<your mail7_api_key>' -e 'MAIL7_BASE_URL=<MAIL7_BASE_URL>' -- npx -y mail7-mcp@0.1.1
JSON configuration (Claude Desktop, Cursor, VS Code) 
{
    "mcpServers": {
        "mail7-email-validation": {
            "command": "npx",
            "args": [
                "-y",
                "mail7-mcp@0.1.1"
            ],
            "env": {
                "MAIL7_API_KEY": "<your mail7_api_key>",
                "MAIL7_BASE_URL": "<MAIL7_BASE_URL>"
            }
        }
    }
}

Environment variables

  • MAIL7_API_KEY secret Mail7 API key. Optional, but anonymous callers are limited to 5 checks per minute and a 25-address bulk sample. Get one at https://mail7.net/account/
  • MAIL7_BASE_URL Override the API endpoint. Defaults to https://mail7.net/api

Documentation

From the project's README on GitHub, refreshed weekly. Links open on GitHub.

Contents
  1. Mail7 MCP server
  2. Install
  3. Tools
  4. How results are shaped
  5. Notes for large lists
  6. Development
  7. License

Mail7 MCP server

Email validation for AI assistants. This is an MCP server that gives Claude, Cursor, Windsurf, Cline and any other MCP client four tools: verify a single address, clean a list, check a domain's SPF record, and audit a domain's whole mail configuration.

Honest by design: Mail7 answers Valid, Not Valid or Unknown, and the tool descriptions tell the model in plain words that Unknown means "could not be verified", not "bad". An assistant using this server will not silently delete addresses it could not check.

Install

Node 18+ required. No install step - the server runs through npx.

Claude Code

claude mcp add mail7 --env MAIL7_API_KEY=your_key -- npx -y mail7-mcp

Claude Desktop (claude_desktop_config.json), Cursor (~/.cursor/mcp.json), and most other clients use the same shape:

{
  "mcpServers": {
    "mail7": {
      "command": "npx",
      "args": ["-y", "mail7-mcp"],
      "env": { "MAIL7_API_KEY": "your_key" }
    }
  }
}

Get an API key at mail7.net/account. The server also runs without one, but anonymous callers are limited to 5 checks per minute and a 25-address free bulk sample - not enough for real work.

VariableDefaultPurpose
MAIL7_API_KEY-Raises rate limits, unlocks full bulk validation
MAIL7_BASE_URLhttps://mail7.net/apiOverride the API endpoint

Tools

ToolWhat it does
validate_emailOne address: syntax, MX, disposable-domain check, live SMTP mailbox probe
validate_emailsUp to 50 addresses per call, with a Valid / Not Valid / Unknown summary
check_domainFull mail-config audit graded A-F: MX, SPF, DKIM, DMARC, MTA-STS, TLS-RPT, DNSSEC, BIMI
check_spfSPF record, mechanisms, lookup count and misconfigurations

Ask your assistant things like:

  • "Is sales@acme.com a real mailbox?"
  • "Clean this list of signups and tell me which ones bounce."
  • "Why do our emails to customers land in spam? Check ourdomain.com."

How results are shaped

validate_email and validate_emails return structured content alongside the text, so a client that supports structured tool output gets typed fields:

{
  "email": "user@example.com",
  "status": "Unknown",        // "Valid" | "Not Valid" | "Unknown"
  "valid": null,              // true | false | null (null = Unknown)
  "formatValid": true,
  "mxValid": true,
  "smtpValid": false,
  "is_disposable": false,
  "details": "Server accepts all addresses (catch-all) - status unknown"
}

check_domain returns a compact graded summary with a fix for every problem. To see the raw records of one part, call it again with section set to mx, spf, dkim, dmarc, mta_sts, tls_rpt, dnssec, bimi or domain.

Notes for large lists

Every address is a live SMTP conversation, so a check takes seconds, not milliseconds. validate_emails caps at 50 addresses per call on purpose - call it repeatedly with the next chunk rather than pushing a whole file through one call, and never run two calls in parallel (the API serialises one bulk job per client).

Development

npm install
npm run build      # -> dist/
node dist/index.js # speaks MCP over stdio

License

MIT. Part of the Mail7 integrations.

Frequently asked questions

What is Mail7 Email Validation?

Verify email addresses, clean lists, and audit a domain SPF, DKIM, DMARC and MX setup.

How do I install Mail7 Email Validation?

It runs on your machine. In Claude Code: claude mcp add mail7-email-validation -e 'MAIL7_API_KEY=<your mail7_api_key>' -e 'MAIL7_BASE_URL=<MAIL7_BASE_URL>' -- npx -y mail7-mcp@0.1.1. For other clients, paste the JSON configuration from this page into their MCP settings.

Does Mail7 Email Validation need an API key?

Yes. It expects MAIL7_API_KEY, which you set in its configuration.

Is Mail7 Email Validation open source?

Yes. Its code is on GitHub under the MIT license.

Who maintains Mail7 Email Validation?

It is published by dvlop. AI.tn lists it but does not maintain or endorse it.

From the official MCP Registry. Listing is not an endorsement: review a server's code and permissions before giving it access to your data.