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MailTester Email Verification

by mailtester.com · remote · no sign-in to list tools · v1.0.1 · published by com.mailtester

Verify emails (valid/invalid/risky/unknown): MX, SMTP, catch-all, disposable. Free agent key.

Changes · 3
CompareRegistry entry

9 tools: 3 change things and 6 only read.

Scanned Oct 21, 2026

No check matched anything in the tool definitions. No finding is not a safety guarantee. How the checks work.

claude mcp add --transport http email-verification https://app.mailtester.com/mcp

Tools

Open a tool for its reasons and full description. Descriptions are the publisher's own words, shown as they are.

9 tools

Changes things 3Claude Code: ask
  • estimate_costEstimate the credit cost of a verification before running it, and whether the user can afford it.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Estimate the credit cost of a verification before running it, and whether the user can afford it. Provide either a count of emails, a list_id to re-verify, or an operation ('single'/'finder'). Always quote this before proposing anything billable.
  • verify_batchVerify a batch of email addresses (up to 25 per call with an agent key).No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Verify a batch of email addresses (up to 25 per call with an agent key). Returns per-email verdicts and saves a list. Costs 1 credit per email.
  • verify_emailVerify the deliverability of a single email address.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Verify the deliverability of a single email address. Returns a verdict (valid, invalid, risky, unknown). Costs 1 credit.
Only reads 6Claude Code: allow
  • explain_resultExplain what a verification status or reason means in plain English, with a send recommendation.No findings

    Why it is in this group

    • The name "explain_result" says "explain": a word for reading.
    Description, as the server wrote it
    Explain what a verification status or reason means in plain English, with a send recommendation. Covers valid, invalid, catch-all/accept-all, unknown, greylisted, disposable, role, free, spam-trap, abuse, do-not-mail, no-mx, disabled, and network. Use when a user asks what a result means.
  • get_api_keyGet your own free API key for this server (no account needed; 25 email verifications per day).No findings

    Why it is in this group

    • The name "get_api_key" says "get": a word for reading.
    Description, as the server wrote it
    Get your own free API key for this server (no account needed; 25 email verifications per day). Optional: the verification tools already work without a key on a shared trial. Returns the key once — reconnect with 'Authorization: Bearer <api_key>' for your own quota and the list tools.
  • get_batch_statusGet the progress and status of a bulk verification list/job by id.No findings

    Why it is in this group

    • The name "get_batch_status" says "get": a word for reading.
    Description, as the server wrote it
    Get the progress and status of a bulk verification list/job by id.
  • get_credit_balanceGet the current credit balance and a short usage summary for the account.No findings

    Why it is in this group

    • The name "get_credit_balance" says "get": a word for reading.
    Description, as the server wrote it
    Get the current credit balance and a short usage summary for the account.
  • get_listGet the details of a single bulk verification list by its id.No findings

    Why it is in this group

    • The name "get_list" says "get": a word for reading.
    Description, as the server wrote it
    Get the details of a single bulk verification list by its id.
  • list_listsList the user's bulk verification lists/jobs, most recent first.No findings

    Why it is in this group

    • The name "list_lists" says "list": a word for reading.
    Description, as the server wrote it
    List the user's bulk verification lists/jobs, most recent first.

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Install

Pinned to version 1.0.1. Values in angle brackets are yours to fill in.

claude mcp add --transport http email-verification https://app.mailtester.com/mcp

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json
{
  "permissions": {
    "allow": [
      "mcp__email-verification__get_api_key",
      "mcp__email-verification__get_credit_balance",
      "mcp__email-verification__list_lists",
      "mcp__email-verification__get_list",
      "mcp__email-verification__explain_result",
      "mcp__email-verification__get_batch_status"
    ],
    "ask": [
      "mcp__email-verification__verify_email",
      "mcp__email-verification__verify_batch",
      "mcp__email-verification__estimate_cost"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. It assumes the server is installed as email-verification. Review it before you use it.