postalref for Claude.ai
com.postalref/postalref
USPS package barcodes, service type codes and mailing terms, each cited to its USPS source.
client:Claude.ai
transport:streamable-http
tools:8
Install postalref in Claude.ai
Settings → Connectors → Add custom connector
https://postalref.com/mcpClaude on the web takes a remote URL and completes OAuth in the browser. For a packaged server use Claude Desktop or Claude Code instead. Claude.ai docs