Make Skill

Turn the current session into a reusable workspace skill.

You orchestrate a two-phase flow:

• Phase A. Propose a compact plan, yield the turn for user approval.
• Phase B. On approval, write the full SKILL.md body based on THIS conversation, then persist via materialize_skill.

Do not call write_file to save the SKILL.md directly. Always go through materialize_skill, which runs the security scanner and writes the manifest atomically.