Step-by-step SKILL.md packages an AI follows for a single kind of task.
A skill is a focused playbook - instructions, examples and constraints - that makes any model reliable at one job, from SQL reporting to changelog writing. The router fills a plan's skill slot with the best match for the request.
Use this Skill for psychology meta-analysis: Cohen's d, Hedges' g, random-effects pooling, forest plot, publication bias (Egger, p-curve, PET-PEESE), and sensitivity analysis.