Feature Request: Allow sub-agents to invoke lazy-loaded skills

Feature Request

Is your feature request related to a problem?

Sub-agents (spawned via the Agent tool) currently cannot invoke lazy-loaded skills (e.g., /commit, /simplify, /review-pr). Skills are only available in the main conversation context. The only workaround is preloading skill content via the skills frontmatter field, which embeds the full definition statically rather than enabling dynamic invocation.

This limits the composability of agents and skills — two of Claude Code's most powerful primitives.

Describe the solution you'd like

Allow sub-agents to dynamically invoke lazy-loaded skills via the Skill tool, just like the main conversation can. This could be:

1. Opt-in inheritance — a flag like inherit_skills: true in the agent config that passes available skills through to sub-agents.
2. Explicit allowlist — similar to the tools field, a skills field that specifies which skills the sub-agent can invoke (not just preload as context).
3. Full parity — sub-agents get the same Skill tool as the parent by default.

Describe alternatives you've considered

• Preloading via skills frontmatter: Works for injecting static content, but doesn't support dynamic invocation or parameterized skill execution.
• Inlining skill logic in the agent prompt: Verbose, hard to maintain, and defeats the purpose of reusable skills.

Additional context

This would make agent + skill composition much more powerful — e.g., a release-manager agent that can invoke /commit, run tests, and create PRs autonomously using existing skills.