usps-webhooks

name	usps-webhooks
description	Receive and verify USPS webhooks (Subscriptions - Tracking API v3.2). Use when setting up USPS tracking webhook handlers, debugging X-HMAC signature verification, creating tracking subscriptions, or handling package tracking events like Out for Delivery, Delivered, or Available for Pickup.
license	MIT
metadata	{"author":"hookdeck","version":"0.1.0","repository":"https://github.com/hookdeck/webhook-skills"}

USPS Webhooks

USPS delivers webhooks through the Subscriptions - Tracking API (v3.2). You create a subscription (POST /subscriptions) with a listenerURL, filterProperties (by Mailer ID or tracking number), and an optional 32-char secret. USPS then POSTs a notification to your listener URL every time a tracked package updates.

When to Use This Skill

• How do I receive USPS tracking webhooks?
• How do I verify the USPS X-HMAC webhook signature?
• How do I create a USPS tracking subscription?
• How do I handle Delivered or Out for Delivery tracking events?
• Why is my USPS webhook signature verification failing?

Verification (core)

USPS signs timestamp + payload — the notification envelope's timestamp field concatenated with the raw, stringified field — with keyed on your subscription , and sends the digest in the header (deprecated alias: ).