What problem does it solve? Building post-purchase order lifecycle logic is error-prone: invalid state transitions, duplicate fulfillments, untracked refunds, and leaked customer PII are common failures. This Skill provides a structured engineering playbook for implementing order status management, shipping label generation, carrier tracking, and return/refund processing with event-sourced state machines and saga orchestration. ## Core Features & Use Cases - Event-Sourced Order State Machine: Model order status as an append-only event log (order_placed, payment_captured, shipped, delivered, returned) with enforced transitions and saga-based compensation branches. - Shipping & Carrier Tracking: Generate labels via carrier APIs (EasyPost, Shippo, DHL, GHTK), validate addresses before billing, and normalize carrier webhook status codes into unified internal milestones. - Refunds & Returns: Process returns with eligibility checks, restock inspection gates, and refunds that always reference the original payment transaction ID. - Use Case: An engineer building a Vietnam-focused e-commerce backend uses this Skill to integrate GHN/GHTK webhook tracking, enforce JWT-scoped agent fulfillment authorization, and prevent automatic restocking before warehouse inspection. ## Quick Start Use the manage-order-fulfillment skill to design the order state machine and shipping integration for my checkout backend.
