USPS Developer Portal MCP. Audit addresses, track packages, and calculate rates in one conversation.

Your agent connects you straight to official USPS data. You don't need to juggle a bunch of websites—your client handles all the postal logistics in one conversation.

Verify US Addresses & Map Locations:
When you get an address from a customer, you gotta make sure it's legit and standardized first. Use verify_usps_address to validate any full U.S. street address against official USPS records; this guarantees your fulfillment metadata is spot-on. If you only have a ZIP code but need the city or state, run that through lookup_usps_city_state.

Need the proper ZIP code for a given street address? You'll use lookup_usps_zip_code to nail down the most accurate five digits.

Determine Shipping Costs & Timelines:
Figuring out shipping costs is simple. For stuff staying within the U.S., you call calculate_domestic_rate and it spits out the exact cost based on weight and destination mail classes. If you're sending packages across borders, use calculate_international_rate to get those overseas rates. You also need to know when it's gonna arrive.

Run a query using get_delivery_commitments, and your agent pulls live delivery commitments, giving you estimated arrival dates based on the service level you pick.

Track Packages & Audit History:
Checking where that package is? It's easy. You give your tracking number to track_usps_package, and it tells you the current status right now. But if you need the full story—like a proper audit trail for complex shipments—you use track_usps_package_advanced. This tool pulls detailed, facility-level event history, showing every single step the package took from origin to destination.

This setup means your agent handles everything: standardizing an address with verify_usps_address, finding the ZIP for a street using lookup_usps_zip_code, cross-referencing that ZIP code back to the city and state via lookup_usps_city_state.

When it comes to rates, you'll use calculate_domestic_rate for U.S.-only shipments or calculate_international_rate if you're sending stuff overseas. You can also get a timeline estimate with get_delivery_commitments, which provides those service-level dates.

For tracking, start by checking the status quickly with track_usps_package. But remember that for deep dives—for seeing every single facility scan and transfer event—you gotta use track_usps_package_advanced. It gives you the granular view of the shipment's entire journey. You don't have to open a browser or switch tabs; your agent just does it all in plain conversation.