Author a new agent skill, or improve an existing one - a folder of instructions an agent loads on demand, from a SKILL.md that works in this harness, in other harnesses, and in any harness reading the Agent Skills standard. Ships a bundled checklist runner and a measured evaluation protocol, not just advice. Use when the user asks you to learn a tool, a site, or a workflow and keep it for later; says "make yourself a skill for X"; asks to write, fix, review, or evaluate a skill; wants a repeated procedure turned into something reusable; or asks whether a skill's description actually fires, what its trigger eval says, or how it performs with and without the skill.
