using-list-subsets
Execution skill. Use when creating, modifying, or reasoning about List Subsets — mirror dimensions, same-dimension-on-two-axes, cohort modeling, restricted dropdowns, iterative performance optimization, or any request involving subsets.
Install
With your agent
Install OMGSkills skill "gopigment/ai-plugins:skills/using-list-subsets" into this agent's normal skills directory: call the OMGSkills MCP get_install_plan tool for your agent and run the script it returns (it installs only the pinned commit and verifies SKILL.md), and stop if MCP or the pin is unavailable. Do not overwrite or change existing skills without asking me.
Manual command
git clone https://github.com/gopigment/ai-plugins /tmp/ai-plugins && ln -s /tmp/ai-plugins/skills/using-list-subsets ~/.claude/skills/using-list-subsetsFrom README
Using List Subsets A subset is a selected group of items from a parent dimension list, usable as its own dimension in metric structure. Use only when they deliver clear modeling or performance benefits. Subset Mental Model A subset behaves as a separate dimension in structures and formulas: Metrics dimensioned by the subset and by the parent are different shapes — not interchangeable without explicit mapping. Subsets inherit items, properties, order, and sharing behavior from the parent list. Deselecting an item from a subset permanently deletes associated datapoints in metrics dimensioned by that subset. Affects all scenarios; not reversed if re-added. Decision Checklist Go through these five gates before recommending a subset: Security or filtering goal? Use Access Rights or view filters/Boolean properties. Do not propose subsets. Smaller input list? If membership changes and there is no iterative/performance need, prefer a separate regular list.