antigravity-skills-reference/skills/writing-skills/references/standards/metadata-standard.md

SKILL.md Metadata Standard

Official frontmatter fields recognized by OpenCode.

Required Fields

---
name: skill-name
description: >-
  Use when [trigger condition].
metadata:
  triggers: keyword1, keyword2, error-message
---

Field	Rules
name	1-64 chars, lowercase, hyphens only, must match directory name
description	1-1024 chars, should describe when to use

Optional Fields

---
name: skill-name
description: Purpose and triggers.
metadata:
  license: MIT
  compatibility: opencode
  author: "your-name"
  version: "1.0.0"
  category: "reference"
  tags: "tag1, tag2"
---

Field	Purpose
license	License identifier (e.g., MIT, Apache-2.0)
compatibility	Tool compatibility marker
metadata	String-to-string map for custom key-values

Name Validation

^[a-z0-9]+(-[a-z0-9]+)*$

Valid: my-skill, git-release, tdd
Invalid: My-Skill, my_skill, -my-skill, my--skill

Common Metadata Keys

Use these conventions for consistency across skills:

Key	Example	Purpose
author	"your-name"	Skill creator
version	"1.0.0"	Semantic version
category	"reference"	Type: reference, technique, discipline, pattern
tags	"react, hooks"	Searchable keywords

Important

Any field not listed here is ignored by OpenCode's skill loader.