Add documentation for all available YAML frontmatter fields, with special
emphasis on `context: fork` which is critical for skills that subagents
should be able to use via the Task tool.
Changes:
- Add YAML Frontmatter Reference section to SKILL.md with complete field table
- Document when to use `context: fork` for subagent-accessible skills
- Add invocation control comparison table
- Update init_skill.py template with commented optional frontmatter fields
This addresses a gap where skills created without `context: fork` could not
be used by subagents, limiting the skill's usefulness in multi-agent workflows.
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>
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