Shopify Polaris Checkout Extensions

If you're building custom checkout experiences for Shopify merchants, this skill helps you scaffold and validate Polaris-based UI extensions. It enforces a validation-first workflow: search the docs, write your code, then validate before returning anything. The skill covers all the extension targets (from cart line items to payment methods to thank you pages) and knows the full component library. One thing worth noting: it's opinionated about using Shopify CLI to scaffold new extensions rather than hand-rolling them, which honestly saves you from version mismatches. The validator is strict about things like not allowing HTML comments, so you'll catch errors before deployment rather than at runtime.