# Skill Authoring > Create or update portable Agent Skills under .agents/skills with concise SKILL.md instructions and optional scripts, references, or assets. Use when a user wants skill-creator behavior that works across Codex, Gemini, Claude Code, OpenCode, or other agents without relying on one vendor's built-in creator. Use when this capability is needed. - Skill: `tomevault-io/skill-authoring-9` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/skill-authoring-9` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/skill-authoring-9/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/skill-authoring-9 --- # Skill Authoring ## Workflow 1. Read `.agents/prompts/create-agent-skill.md` if present. 2. Gather concrete trigger examples and the repeated task the skill should improve. 3. Create `.agents/skills//SKILL.md`. 4. Use frontmatter with only `name` and `description` unless a target explicitly requires more. 5. Add `scripts/`, `references/`, or `assets/` only when they materially reduce repeated work or increase reliability. 6. Test scripts and validate frontmatter. ## Quality Bar Keep skills concise, non-obvious, reusable, project-safe, and actionable. --- # Claude Adapter Generate a project skill at `.claude/skills/skill-authoring/SKILL.md` when the Claude target is enabled. Keep the generated skill body derived from the canonical neutral skill and add only this adapter note. If Claude Code has an official, bundled, or installed equivalent for this capability in the current environment, prefer that native surface and keep the canonical skill as fallback. Do not require Claude Marketplace or user-scope plugin installation. --- > Source: [KiringYJ/biblatex-library](https://github.com/KiringYJ/biblatex-library) — distributed by [TomeVault](https://tomevault.io).