MailTester Ninja
Verify email addresses live against their mail server and find work emails. Nothing stored.
MCP server · by mailtester.ninja
About
MailTester Ninja is an MCP server published by mailtester.ninja. Marketplaces we read that list it: 1 (Official MCP Registry). We first saw it on 2026-10-28 and have recorded no change since. As of our marketplace pass on 2026-11-03.
What it asks for
- Runs remotely
None of the marketplaces we read publishes its tools or the settings it asks for.
Requires: X-API-Key header
What it declares, asks for and runs, in full
Only install plugins from developers you trust. We list what marketplaces publish and do not test plugins.
Works with
- Claude Code
- Codex
- Cursor
- VS Code
- Copilot CLI
A one-click link opens the client, which asks you to confirm before it adds the server.
From the marketplaces that list it and the MCP transport it declares, as each client documents them. We do not test plugins.
Connect
Commands and configs built only from what its marketplaces declare. We do not run them for you and do not test plugins.
As a remote MCP server
Built from what Official MCP Registry declares.
claude mcp add --transport http email-verification https://mcp.mailtester.ninja/mcp --header "X-API-Key: <YOUR_X_API_KEY>"[mcp_servers.email-verification]
url = "https://mcp.mailtester.ninja/mcp"
http_headers = { "X-API-Key" = "<YOUR_X_API_KEY>" }{
"mcpServers": {
"email-verification": {
"url": "https://mcp.mailtester.ninja/mcp",
"headers": {
"X-API-Key": "<YOUR_X_API_KEY>"
}
}
}
}Replace the values in angle brackets with your own. We show the names of the settings, never values.
Where it is published
| Marketplace | Status | Version | Figures | Verified | First seen |
|---|---|---|---|---|---|
| Official MCP Registry (Open the registry record) | Listed | 1.0.1 | No figure published | Not marked |
Each figure is the marketplace's own and is never added up across marketplaces. A marketplace that publishes no figure shows none: no number is not zero.
What changed
- Became a product we track
- Official MCP Registry: appeared
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Found by meaning, not by shared code or a shared repository: similar plugins stay separate products, and this is not a review or a recommendation.
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Data comes from the Official MCP Registry (registry.modelcontextprotocol.io), CC0 1.0. Figures come from our own regular passes over the marketplaces, last read on . We publish no contact details for plugin publishers.