# mailX

> Use this tool when you need to diagnose and resolve email deliverability issues or perform DNS lookups, as it provides a suite of 20+ tools for authentication checks, deliverability diagnostics, and connectivity testing. It accepts various inputs such as domain names and email addresses, and outputs JSON data for easy integration. Ideal for use cases where email delivery problems need to be identified and fixed, with a simple and authentication-free interface.

Canonical page: https://skillsregistry.net/skills/mailx  
JSON: https://api.skillsregistry.net/v1/skills/mailx

## Description

mailX exposes 20+ email deliverability and DNS tools via MCP, organized into five categories: authentication checks (SPF, DKIM, DMARC, BIMI), deliverability diagnostics (blacklist scanning, SMTP/IMAP testing), DNS lookups (MX, TXT, CNAME, PTR), record generators, and connectivity testing. No authentication required. Built as a free alternative to MXToolbox with a clean JSON API.

## Trust

- **Trust score (0–1):** 0.30
- **Verification tier:** unverified
- **Last scanned:** 2026-09-02

## Facts

- **Version:** 1.0.0
- **Skill type:** atomic
- **Execution layer:** mcp-remote
- **Runtime environment:** api
- **Category:** communication
- **Updated:** 2026-09-02

## Source

- **Source listing:** [PulseMCP](https://www.pulsemcp.com/servers/mailx)

## Use it

Resolve this record through the SkillsRegistry MCP server (no auth, read-only):

```
claude mcp add --transport http --scope user skillsregistry https://api.skillsregistry.net/mcp
```

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "get_skill",
    "arguments": {
      "slug": "mailx"
    }
  }
}
```

REST: `GET https://api.skillsregistry.net/v1/skills/mailx` · pull for local use: `GET https://api.skillsregistry.net/v1/skills/mailx/pull`

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SkillsRegistry indexes agent skills from public registries and GitHub. Skills we have analysed are scanned with Circle-IR and scored on six dimensions; each listing states its scan coverage. More: https://skillsregistry.net/llms.txt