Feature: Model selection in skill frontmatter

Allow skills to declare a preferred model via a model field in frontmatter. Claude Code's skill loader would switch the active model for that skill's execution.

---
name: create-feature-branch
description: Create standardised feature branch
model: haiku
---

Why

Many skills are mechanical (git operations, ticket creation, checklist validation) and don't need the most capable model. The only workaround today is dispatching to a subagent via the Task tool — but the orchestration overhead (Opus reading the skill, deciding to dispatch, processing the result) can cost more than just letting Opus do the work directly.

A native model switch at the skill loader level would:

• Reduce cost — simple skills run on Haiku/Sonnet instead of Opus
• Reduce latency — faster models respond faster for mechanical tasks
• Zero orchestration tax — no subagent dispatch overhead

Suggested behaviour

• model field sets the default for that skill's execution
• User settings can override per-skill (e.g. force Opus for everything, or remap specific skills)
• No model field = unchanged behaviour (uses session model)

Real-world assessment

Assessment of ~20 custom skills showed roughly:

• ~5 Haiku — branch creation, tag checkout, ticket creation (mechanical, template-driven)
• ~9 Sonnet — code review checks, test validation, release readiness (pattern matching against rules)
• ~5 Opus — brainstorming, architectural planning, debugging (deep reasoning, creative exploration)

That's significant cost savings for teams using skills heavily.