skill-authoring
SKILL.md
Skill Authoring Guide
This skill provides guidance for writing Agent Skills that comply with the agentskills.io specification.
When to Use
- Creating a new skill for this repository
- Reviewing a skill PR for compliance
- Checking if an existing skill follows best practices
- Understanding token budgets and progressive disclosure
Constraints
name: 1-64 chars, lowercase + hyphens, match directorydescription: 1-1024 chars, explain WHAT and WHEN- SKILL.md: <500 tokens (soft), <5000 (hard)
- references/*.md: <1000 tokens each
Structure
SKILL.md(required) - Instructionsreferences/(optional) - Detailed docsscripts/(optional) - Executable code
Frontmatter: name (lowercase-hyphens), description (WHAT + WHEN)
Progressive Disclosure
Metadata (~100 tokens) loads at startup. SKILL.md (<5000 tokens) loads on activation. References load only when explicitly linked (not on activation). Keep SKILL.md lean.
Reference Loading
References are JIT (just-in-time) loaded:
- Only files explicitly linked via
[text](references/file.md)load - Link to files, not folders -
[Recipes](references/recipes/README.md)not[Recipes](references/recipes/) - Each file loads in full (not sections)
- No caching between requests - write self-contained files
- Use recipes/services patterns for multi-option skills
See REFERENCE-LOADING.md for details.
Validation
# Run from the scripts directory
cd scripts
npm run references # Validate all skill links
npm run tokens -- check # Check token limits
Integrity Checks
When reviewing or authoring skills, verify:
- No broken links - All referenced files exist
- No orphaned references - All reference files are linked
- Token budgets - References under 1000 tokens (split if exceeded)
- No duplicates - Consolidate repeated content
- No out-of-place guidance - Service-specific content belongs in service-specific references
See Validation for detailed procedures.
Reference Documentation
- Guidelines - Detailed writing guidelines
- Token Budgets - Limits and splitting guidance
- Reference Loading - How references load
- Checklist - Pre-submission checklist
- Validation - Link and reference validation
- agentskills.io/specification - Official spec
Weekly Installs
21
Repository
microsoft/github-copilot-for-azureFirst Seen
Feb 3, 2026
Security Audits
Installed on
github-copilot19
opencode18
gemini-cli17
codex17
antigravity14
claude-code14