Shopify Checkout Contract Guard Skill

Protect Shopify's post-cart commerce boundary after theme, cart, market, app, or checkout changes.

• Inventory Shop Pay, Markets, selling plans, payment and delivery methods, Shopify Functions, checkout extensions, shipping profiles, and checkout apps
• Validate a normalized checkout contract and record unknown dependencies as release gates
• Compare approved baselines with current configuration
• Generate exact retest requirements for changed contracts
• Run an authorized cart-to-checkout handoff test without submitting customer or payment data

This skill does not submit payment or create an order during its default checkout test.