nexus-skill-writer-mdlisted

# Nexus Skill Writer Produce a **complete, production-ready skill** every session — not a draft, not a skeleton. --- ## Required Directory Layout ``` skill-name/ ├── SKILL.md ← entry point, <500 lines ├── checklists/ │ └── execution-checklist.md ├── anti-patterns/ │ └── common-mistakes.md └── validation/ └── output-validation.md ``` Every SKILL.md must have YAML frontmatter: ```yaml --- name: nexus-{skill-name} # kebab-case, unique, descriptive description: > # THE TRIGGER MECHANISM — be explicit and dense Use this skill when ... [detailed trigger conditions]. Trigger phrases include: "...", "...", "...". Also trigger when ... [edge cases]. When in doubt, use this skill. --- ``` The `description` is the single most important field. Claude selects skills based only on name + description. A vague description means the skill never triggers. Under-triggering is the #1 skill failure mode. --- ## Phase 0 — Skill Classification Before writing anything, classify the request: **New skill or extension?** 1. Scan `available_skills` in the system prompt. 2. If an existing skill covers 60%+ of the use case, offer to extend instead. 3. Present options as a table: | Option | Best when | Risk | |--------|-----------|------| | Extend existing | Same domain, similar triggers | May bloat the existing skill | | Create new | Distinct triggers, different output contract | Maintenance overhead | | Merge two skills | Over