Skip to content
mcp/harbor
Grok

Postio — UK Address, Postcode, Email & Phone Validation for Grok

uk.co.postio/postcode-address-validation

Validate UK addresses, postcodes, emails and phone numbers — Royal Mail PAF, live SMTP and HLR.

client:Grok transport:stdio runtime:npm

Install Postio — UK Address, Postcode, Email & Phone Validation in Grok

.mcp.json (in your project root)

Held in this page only — never stored, logged, or sent anywhere but back to your screen. 

{
  "mcpServers": {
    "postcode-address-validation": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@postio/mcp"
      ],
      "env": {
        "POSTIO_API_KEY": "<POSTIO_API_KEY>",
        "POSTIO_BASE_URL": "<POSTIO_BASE_URL>"
      }
    }
  }
}

Grok Build reads Claude Code's .mcp.json and Claude Desktop's config unchanged, so a server you have already set up there needs nothing new. The Grok web app and X integration do not take custom servers. Grok docs

Postio — UK Address, Postcode, Email & Phone Validation in other clients

Postio — UK Address, Postcode, Email & Phone Validation MCP server