# Quick Rule > Quickly draft a Shopify Liquid rule from official documentation and well-known patterns. Use when the topic is a well-documented Shopify feature, standard Liquid pattern, or common e-commerce technique that does not require deep cross-theme research. Faster alternative to research-shopify-rule. Use when this capability is needed. - Skill: `tomevault-io/quick-rule` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/quick-rule` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/quick-rule/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Docs & Writing - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/quick-rule --- # Quick rule -- write a rule from known patterns You are writing a Shopify Liquid rule for a well-documented topic. This skill is the fast path: lean on Shopify's official documentation and your own knowledge rather than mining local themes. The topic is: **$ARGUMENTS** Read the reference files in this skill's directory before starting: - [references/rule-template.md](references/rule-template.md) -- the format every rule must follow - [references/existing-coverage.md](references/existing-coverage.md) -- what Shopify's cursor rules already cover (avoid duplicating) --- ## When to use this skill vs /research-shopify-rule | Use `/quick-rule` when | Use `/research-shopify-rule` when | |:---|:---| | The pattern is well-documented on shopify.dev | The pattern has little or no official documentation | | Shopify Liquid docs fully describe the objects and filters involved | The topic involves undocumented workarounds or community-discovered tricks | | The topic is a single, focused technique | The topic spans multiple interacting patterns | | Examples from official docs are sufficient | You need cross-theme comparison to find the best approach | | Complexity is basic or intermediate | Complexity is advanced (nested loops, recursive-like patterns) | If you discover during Phase 1 that the topic is more complex than expected, **stop and suggest switching to `/research-shopify-rule`** before investing time in a draft. --- ## Phase 1 -- Scope ### 1.1 Parse the topic Break down `$ARGUMENTS`: - What Liquid objects, filters, tags, or Shopify features are involved? - Is this a single technique or does it combine multiple concepts? - What complexity level does this feel like: basic, intermediate, or advanced? ### 1.2 Check for overlap Use the three-level overlap check: 1. Read `references/existing-coverage.md` -- does this overlap with Horizon's cursor rules? If so, note what the existing rules cover and focus on what they do NOT cover. 2. Check `rules/INDEX.md` for existing rules on the topic. If a related rule exists, determine whether to extend it or create a new one. 3. If `shopify-themes/horizon/` is present, scan its `.cursor/rules/` for the latest coverage. This takes priority over the static summary. Also check `rules/BACKLOG.md` -- if this topic is there, note its scope and evidence. ### 1.3 Complexity guardrail Evaluate whether this topic is suitable for the quick path. Flag it as **too complex** if any of these are true: - The official Shopify docs do not adequately document the pattern - The topic involves undocumented Liquid behavior or workarounds - Multiple interacting patterns are needed (more than one rule's worth of content) - Real-world implementations vary significantly across themes and there is no clear best practice - The topic requires understanding Shopify platform quirks not covered in docs If the topic is too complex, tell the user: > This topic appears more complex than a quick rule can cover well. Specifically: [reason]. I recommend using `/research-shopify-rule $ARGUMENTS` instead, which includes cross-theme research and pattern analysis phases. Wait for the user to decide before proceeding. ### 1.4 Quick local scan (optional) If the `shopify-themes/` directory contains themes, do a fast scan for relevant snippets or sections -- but only to supplement web research, not as a primary source. Limit this to a few targeted greps. If `shopify-themes/` is empty or does not exist, skip this step entirely. The quick-rule workflow does not depend on local themes. ### 1.5 Present scope Tell the user: - The topic you understood from their input - The target rule filename and category - Any overlap with existing rules or cursor rules - Whether you plan to create a new rule or extend an existing one - Confirmation that the topic is suitable for the quick path Wait for user confirmation before proceeding to Phase 2. --- ## Phase 2 -- Draft ### 2.1 Web research Research the topic using Shopify's official documentation. Focus on: - **shopify.dev** -- Liquid reference, theme architecture docs, API docs - **Shopify Community forums** at community.shopify.dev -- for common gotchas and edge cases - **Links the user provides** as additional context For each key aspect of the pattern, look for: - Official syntax and parameters - Documented limitations or caveats - Official code examples - Changelog entries (when was this feature added or changed?) ### 2.2 Write the rule Draft the rule following the template in `references/rule-template.md`. Apply these principles: **Frontmatter** - Choose the most appropriate category - Set complexity to `basic` or `intermediate` (if you need `advanced`, reconsider whether this should be a `/research-shopify-rule`) - Include tags that an AI agent would search for when encountering the problem - List all Liquid objects and filters the pattern uses **Problem section** - Be specific about the gap -- what would an AI agent get wrong without this rule? - Frame it as a limitation, challenge, or non-obvious behavior **Solution section** - Provide a complete, copy-paste ready code example - Annotate each step so an AI agent understands the why, not just the what - Use `{% liquid %}` blocks for multiline logic (Shopify convention) **How it works section** - Walk through each step of the pattern - Explain why each line exists **Variations section** - Include alternative approaches if they exist in official documentation - Note trade-offs for each variation - If local themes were available and showed an interesting variation, include it with a source reference **Source references section** - Link to the relevant Shopify documentation pages (use full URLs) - If themes in `shopify-themes/` were consulted, include theme file references - If no local themes were available, state: "Pattern documented from Shopify official documentation." **Edge cases and gotchas** - Pull from documentation warnings, community forum issues, and known Liquid quirks - Focus on things an AI would not know from reading the basic docs **Related section** - Link to related rules if they exist in `rules/` - Suggest topics that could become future rules ### 2.3 Present draft Show the complete draft to the user. Ask for feedback. Iterate based on their input. --- ## Phase 3 -- Finalize 1. Write the rule to `rules//.md` - Use kebab-case for filenames - Create the category folder if it doesn't exist yet 2. Update `rules/INDEX.md`: - Add the new rule under the appropriate category heading - Format: `- [Rule Title](category/rule-name.md) -- one-line description` 3. If this topic came from `rules/BACKLOG.md`, update the entry: - Set status to `done` - Add the rule link 4. Suggest 1-2 related topics that could become future rules --- ## Important guidelines - Never invent Liquid filters, tags, or objects. Only use what exists in Shopify's Liquid implementation. - When showing code examples, use the `{% liquid %}` tag for multiline logic blocks. - Always test that code examples are syntactically valid Liquid. - If a pattern involves metafields, specify the metafield namespace and type clearly. - Cross-reference Shopify's official Liquid docs when unsure about object properties or filter behavior. - The rules are standalone content. Do not reference project-specific paths within rule content. - Source references should use full URLs for Shopify docs and relative theme paths for local themes (e.g., `dawn/snippets/price.liquid`). - This is the fast path. If research is taking significantly longer than expected, reconsider whether `/research-shopify-rule` would be more appropriate. --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/teamdijon) — claim your Tome and manage your conversions.