FabTally Valid vs Mailbuttons

In-depth architectural comparison of the FabTally Valid and Mailbuttons MCP servers. Compare execution transports, security boundaries, tool capabilities, quality scores, and ready-to-paste client installation snippets for Claude, Cursor, Windsurf, and VS Code.

Which MCP Server Should You Choose?

F

Choose FabTally Valid when:

• You need dedicated capabilities in the Communication domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).
• Primary tools included: validate_vat, validate_iban, validate_email.

Explore FabTally Valid Details

Choose Mailbuttons when:

• You need dedicated capabilities in the Communication domain.
• You prefer local stdio subprocess transport architecture.
• Your security boundary fits: No auth required (Free / Open Source).

Explore Mailbuttons Details

Feature & Specification Comparison

Specification	F FabTally Valid Communication	Mailbuttons Communication
Summary	Validation suite: EU VAT (VIES), IBAN mod-97, email (MX+disposable), geo place lookup, VIN decode.	Governed email for AI agents: sandbox inboxes, server-side policy gate, tamper-evident audit.
Category & Scope	Communication	Communication
Quality signal

Tools & Capabilities Breakdown

Ready-to-Paste Client Configurations

Paste either (or both) of these JSON server blocks into your client config file (e.g. claude_desktop_config.json or ~/.cursor/mcp.json).

{
  "mcpServers": {
    "fabtally-valid": {
      "command": "npx",
      "args": [
        "-y",
        "fabtally-valid-mcp"
      ]
    }
  }
}

{
  "mcpServers": {
    "mailbuttons-2": {
      "command": "npx",
      "args": [
        "-y",
        "skills"
      ]
    }
  }
}

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