About Mailx Tools
Mailx Tools is an email deliverability plugin and MCP server for Claude and other MCP clients. It audits email authentication and provides DNS fixes, with SMTP/IMAP login tests available to compatible clients.
Key features
- 01Audit SPF, DKIM, DMARC and BIMI
- 02Check blacklists and DNS
- 03Generate corrective DNS records
- 04Test SMTP and IMAP logins
Use cases
- 01Diagnose a domain's email authentication
- 02Prepare DNS changes to improve deliverability
- 03Verify SMTP or IMAP login connectivity
MCP support
Exposes email deliverability tools through the mailX MCP server. Other MCP clients can connect to the hosted endpoint, which also includes SMTP/IMAP login tests.
Configuration
Remote servers need no local install. Pick your client, then copy the config or install in one click.
https://themailx.com/mcpclaude mcp add --transport http mailx-skills https://themailx.com/mcp{"mcpServers":{"mailx-skills":{"type":"http","url":"https://themailx.com/mcp"}}}Open in Cursor{"servers":{"mailx-skills":{"type":"http","url":"https://themailx.com/mcp"}}}Open in VS Code{"mcpServers":{"mailx-skills":{"type":"http","url":"https://themailx.com/mcp"}}}{"mcpServers":{"mailx-skills":{"serverUrl":"https://themailx.com/mcp"}}}Run commands in a terminal; paste JSON into the client’s MCP config and restart. Servers that need sign-in will prompt on first connect.
Tools
16| Parameter | Type | Required | Description |
|---|---|---|---|
| domain_name | string | Yes | The domain to check SPF records for, e.g. example.com |
Details
From the project READMEmailX Skills
The mailX plugin for Claude: it teaches Claude to diagnose and fix email deliverability issues (SPF, DKIM, DMARC, BIMI, blacklists, DNS) and connects the mailX server automatically.
Plugins
mailx
Audits a domain's email authentication, explains each result, and gives the exact DNS records to fix it. Includes the email-deliverability skill, the mailX server (https://themailx.com/mcp/claude), and two commands: /mailx:audit and /mailx:setup-dns. Details in plugins/mailx/README.md.
Install
Claude Code
/plugin marketplace add Mailwarm/mailx-skills
/plugin install mailx@mailx-skills
Claude.ai
Add the mailX connector from Claude's directory, or add a custom connector with the URL https://themailx.com/mcp/claude. To add the skill on its own, download email-deliverability.zip and upload it under Settings → Capabilities → Skills.
Other MCP clients
Cursor, VS Code, Windsurf and other clients can connect to https://themailx.com/mcp, which also includes the SMTP/IMAP login tests. Setup guide: themailx.com/docs/mcp.
Structure
mailx-skills/
├── .claude-plugin/
│ └── marketplace.json
└── plugins/
└── mailx/
├── .claude-plugin/
│ ├── plugin.json
│ └── icon.png
├── .mcp.json
├── README.md
├── LICENSE
├── commands/
│ ├── audit.md
│ └── setup-dns.md
└── skills/
└── email-deliverability/
├── SKILL.md
└── references/diagnosis.md
Links
License
MIT, by Mailwarm Inc.
Comments
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