Why Model Selection Transforms Claude Code Skill Performance

Most Claude Code skill developers leave significant optimization opportunities untapped by neglecting the model field and other critical frontmatter configuration options. Strategic model assignment—routing lightweight tasks to Haiku and complex reasoning work to Sonnet—directly reduces costs while improving execution speed. Mastering fields like `when_to_use`, `paths`, and `effort` not only transforms skill efficiency but also protects your context window from unnecessary bloat.