Proposal: Hierarchical skill grouping and tab navigation for /skill selector

Motivation & Problem Statement

As users and agent ecosystems accumulate more specialized skills across directories and domain categories (e.g., devops/ci, security/audit, data/analytics), managing and browsing skills with /skill becomes challenging:

1. Skills are displayed in a flat list or without clear category boundaries, making visual scanning difficult when dozens of skills are installed.
2. The UX is inconsistent with the /model selector, which already provides intuitive top-level tab strip navigation.
3. Typing /skill into the input prompt triggers argument autocomplete rather than directly launching the interactive selector dialog.

Proposed Solution

We propose enhancing the /skill interactive selector dialog with hierarchical grouping and tab navigation:

1. Tab Strip Group Navigation:

   • Render top-level group tabs ([All] [Group A] [Group B] ... [Uncategorized]) at the top of the dialog.
   • Support Tab / Shift-Tab navigation with brand highlighting, identical to TabbedModelSelectorComponent.

2. Hierarchical Category Resolution:

   • Resolve skill categories based on standard metadata precedence:
     1. groups (string array in skill YAML frontmatter)
     2. category (slash-delimited string in skill YAML frontmatter)
     3. Parent directory path relative to skill root
     4. Fallback to Uncategorized

3. Subtree Fuzzy Search:

   • Active search queries filter across both direct skills and nested sub-categories.
   • When no query is typed, display clean category-scoped lists.

4. Direct Command Invocation:

   • Running /skill without arguments launches the interactive dialog immediately.

Reference Implementation & Prior Work

A complete, fully tested implementation of this proposal was drafted in closed PR #2995 with full test coverage (skill-selector.test.ts, skill-group-tree.test.ts), busy-state guards, and changeset.

Questions for Maintainers

• Does the Moonshot team support adopting tabbed category navigation for /skill aligned with the /model selector UX?
• If aligned with the roadmap, would maintainers give /approve to reopen/review PR #2995?

Thank you for your feedback!

Start by reviewing closed PR #2995 and its mentioned tests, skill-selector.test.ts and skill-group-tree.test.ts. Compare the existing /skill behavior with the /model selector and the TabbedModelSelectorComponent reference. Done means a maintainer-approved implementation covers the proposed grouping, navigation, search, and direct invocation behavior with the stated tests and changeset.