postalref for Grok
com.postalref/postalref
USPS package barcodes, service type codes and mailing terms, each cited to its USPS source.
client:Grok
transport:streamable-http
tools:8
Install postalref in Grok
.mcp.json (in your project root)
{
"mcpServers": {
"postalref": {
"type": "http",
"url": "https://postalref.com/mcp"
}
}
}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