Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/aegntic/compound-engineering/create-agent-skillsnpx skills add aegntic/compound-engineering --skill create-agent-skillsgit clone --depth 1 https://github.com/aegntic/compound-engineeringWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/aegntic/compound-engineering/create-agent-skills)<a href="https://agentmods.dev/skills/aegntic/compound-engineering/create-agent-skills"><img src="https://agentmods.dev/badge/skills/aegntic/compound-engineering/create-agent-skills.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00046 | $0.02176 |
| Opus 5 | $0.00023 | $0.01088 |
| Sonnet 5 | $0.00009 | $0.00435 |
| Haiku 4.5 | $0.00005 | $0.00218 |
Grade A, and why
create-agent-skills scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
This is a copy
92% identical to create-agent-skills — 17 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
How it starts
The opening of the file, as written. The whole thing — 285 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Creating Skills & Commands
This skill teaches how to create effective Claude Code skills following the official specification from code.claude.com/docs/en/skills.
Commands and Skills Are Now The Same Thing
Custom slash commands have been merged into skills. A file at .claude/commands/review.md and a skill at .claude/skills/review/SKILL.md both create /review and work the same way. Existing .claude/commands/ files keep working. Skills add optional features: a directory for supporting files, frontmatter to control invocation, and automatic context loading.
If a skill and a command share the same name, the skill takes precedence.
When To Create What
Use a command file (commands/name.md) when:
- Simple, single-file workflow
- No supporting files needed
- Task-oriented action (deploy, commit, triage)
Use a skill directory (skills/name/SKILL.md) when:
- Need supporting reference files, scripts, or templates
- Background knowledge Claude should auto-load
- Complex enough to benefit from progressive disclosure
Both use identical YAML frontmatter and markdown content format.
Standard Markdown Format
Use YAML frontmatter + markdown body with standard markdown headings. Keep it clean and direct.
---
name: my-skill-name
description: What it does and when to use it
---
# My Skill Name
## Quick Start
Immediate actionable guidance...
## Instructions
Step-by-step procedures...
## Examples
Concrete usage examples...
Frontmatter Reference
All fields are optional. Only description is recommended.
| Field | Required | Description |
|---|---|---|
name |
No | Display name. Lowercase letters, numbers, hyphens (max 64 chars). Defaults to directory name. |
description |
Recommended | What it does AND when to use it. Claude uses this for auto-discovery. Max 1024 chars. |
argument-hint |
No | Hint shown during autocomplete. Example: [issue-number] |
disable-model-invocation |
No | Set true to prevent Claude auto-loading. Use for manual workflows like /deploy, /commit. Default: false. |
user-invocable |
No | Set false to hide from / menu. Use for background knowledge. Default: true. |
allowed-tools |
No | Tools Claude can use without permission prompts. Example: Read, Bash(git *) |
model |
No | Model to use. Prefer explicit IDs. In this repo, default reasoning work to claude-sonnet-4.6, GPT code/review work to gpt-5.3-codex via platform overrides, and reserve claude-haiku-4.5 / gpt-5.4-mini for lightweight search or research tasks. |
context |
No | Set fork to run in isolated subagent context. |
agent |
No | Subagent type when context: fork. Options: Explore, Plan, general-purpose, or custom agent name. |
What ships with it
25 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
- references/api-security.md 6.0 KB
- references/be-clear-and-direct.md 13 KB
- references/best-practices.md 9.1 KB
- references/common-patterns.md 14 KB
- references/core-principles.md 12 KB
- references/executable-code.md 4.3 KB
- references/iteration-and-testing.md 13 KB
- references/official-spec.md 5.1 KB
- references/recommended-structure.md 3.9 KB
- references/skill-structure.md 4.4 KB
- references/using-scripts.md 3.0 KB
- references/using-templates.md 2.9 KB
- references/workflows-and-validation.md 12 KB
- templates/router-skill.md 1.5 KB
- templates/simple-skill.md 636 B
- workflows/add-reference.md 2.2 KB
- workflows/add-script.md 2.1 KB
- workflows/add-template.md 1.9 KB
- workflows/add-workflow.md 2.9 KB
- workflows/audit-skill.md 3.5 KB
- workflows/create-domain-expertise-skill.md 18 KB
- workflows/create-new-skill.md 5.5 KB
- workflows/get-guidance.md 3.0 KB
- workflows/upgrade-to-router.md 3.7 KB
- workflows/verify-skill.md 5.1 KB
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 5d ago First seen · 285 lines · 46 tokens per session scan A 6aca66a5c232
create-agent-skills is a skill published in the GitHub repository aegntic/compound-engineering (2 stars, last pushed 2mo ago), licensed MIT. It adds 46 tokens to every session and 2,176 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 92% identical to create-agent-skills, differing in 17 lines, and is treated as a copy.
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standards
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