概要
This skill empowers developers to seamlessly integrate PayPal's comprehensive payment ecosystem into their applications. It provides standardized implementation patterns for Express Checkout using Smart Payment Buttons, server-side order management via REST APIs, and complex recurring billing structures. Beyond simple transactions, the skill covers critical production requirements such as Instant Payment Notification (IPN) verification, webhook handling, and robust error management, ensuring a secure and reliable checkout experience for e-commerce platforms and SaaS products.