Build Shopify apps, extensions, themes using GraphQL Admin API, Shopify CLI, Polaris UI, and Liquid.
SkillScore87Maintained
Automatic
◆Coding pack
Last verified 8/11/2026
What it changes
Passed 20 of 23 test cases with the skill, and 18 of 23 without it.
Without skill78%
With skill87%
Checks it passed that the model alone missed
Uses checkout_ui_extension
Uses function as the type value
2 fixed18 passed either way3 still failing0 broke
Pass-rate lift
+9 pp
Tokens
+142%
Agent turns
0%
Response time
-37%
Model gemini-3.6-flashMeasured 8/11/2026v120 of 23 cases passed with skill
Tokens, turns and time describe resource use, not a dollar price.
See it in action
One of 2 test cases the skill fixed. Same model, same prompt, with and without the skill.
1 of 2
Prompt
When invoking CLI tools to create a brand new checkout customization interface, what parameter value is passed to the extension type argument?
What was checked, without and with the skill
Checked
Without skill
With skill
Uses checkout_ui_extension
Missed
Passed
case-05 · gemini-3.6-flash · 8/11/2026 · answers are capped and redacted
What's inside
The instructions your model reads when the skill loads.
SKILL.md365 lines8 filesincludes scripts
Shopify Development Skill
Use this skill when the user asks about:
Building Shopify apps or extensions
Creating checkout/admin/POS UI customizations
Developing themes with Liquid templating
Integrating with Shopify GraphQL or REST APIs
Implementing webhooks or billing
Working with metafields or Shopify Functions
ROUTING: What to Build
IF user wants to integrate external services OR build merchant tools OR charge for features:
→ Build an App (see references/app-development.md)
IF user wants to customize checkout OR add admin UI OR create POS actions OR implement discount rules:
→ Build an Extension (see references/extensions.md)
IF user wants to customize storefront design OR modify product/collection pages:
→ Build a Theme (see references/themes.md)
IF user needs both backend logic AND storefront UI:
→ Build App + Theme Extension combination
Build Shopify applications, extensions, and themes using GraphQL/REST APIs, Shopify CLI, Polaris UI components, and Liquid templating. Capabilities include app development with OAuth authentication, checkout UI extensions for customizing checkout flow, admin UI extensions for dashboard integration, POS extensions for retail, theme development with Liquid, webhook management, billing API integration, product/order/customer management. Use when building Shopify apps, implementing checkout customiz