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 skills add Jerrylalala/compound-engineering --skill create-agent-skillsgit clone --depth 1 https://github.com/Jerrylalala/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/jerrylalala/compound-engineering/create-agent-skills)<a href="https://agentmods.dev/skills/jerrylalala/compound-engineering/create-agent-skills"><img src="https://agentmods.dev/badge/skills/jerrylalala/compound-engineering/create-agent-skills/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/jerrylalala/compound-engineering/create-agent-skills"><img src="https://agentmods.dev/badge/skills/jerrylalala/compound-engineering/create-agent-skills.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00044 | $0.02089 |
| Opus 5.5 | $0.00018 | $0.00836 |
| Sonnet 5.5 | $0.00009 | $0.00418 |
| Haiku 4.5 | $0.00004 | $0.00209 |
Grade A, and why
creating-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 2mo 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
91% identical to creating-agent-skills — 55 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 — 355 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Creating Agent Skills
This skill teaches how to create effective Claude Code Skills following Anthropic's official specification.
Core Principles
1. Skills Are Prompts
All prompting best practices apply. Be clear, be direct. Assume Claude is smart - only add context Claude doesn't have.
2. Standard Markdown Format
Use YAML frontmatter + markdown body. No XML tags - use standard markdown headings.
---
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...
3. Progressive Disclosure
Keep SKILL.md under 500 lines. Split detailed content into reference files. Load only what's needed.
my-skill/
├── SKILL.md # Entry point (required)
├── reference.md # Detailed docs (loaded when needed)
├── examples.md # Usage examples
└── scripts/ # Utility scripts (executed, not loaded)
4. Effective Descriptions
The description field enables skill discovery. Include both what the skill does AND when to use it. Write in third person.
Good:
description: Extracts text and tables from PDF files, fills forms, merges documents. Use when working with PDF files or when the user mentions PDFs, forms, or document extraction.
Bad:
description: Helps with documents
Skill Structure
Required Frontmatter
| Field | Required | Max Length | Description |
|---|---|---|---|
name |
Yes | 64 chars | Lowercase letters, numbers, hyphens only |
description |
Yes | 1024 chars | What it does AND when to use it |
allowed-tools |
No | - | Tools Claude can use without asking |
model |
No | - | Specific model to use |
Naming Conventions
Use gerund form (verb + -ing) for skill names:
processing-pdfsanalyzing-spreadsheetsgenerating-commit-messagesreviewing-code
What ships with it
2 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.
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.
- 2mo ago First seen · 355 lines · 44 tokens per session scan A 05626484c1eb
creating-agent-skills is a skill published in the GitHub repository Jerrylalala/compound-engineering (6 stars, last pushed 5mo ago), licensed MIT. It adds 44 tokens to every session and 2,089 once invoked, about $0.0002 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 91% identical to creating-agent-skills, differing in 55 lines, and is treated as a copy.
creating-agent-skills compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| creating-agent-skillsJerrylalala/compound-engineering | Skill | 6 | 5mo ago | MIT | A | 44 | Claude Code |
| imagegenopenai/codex | Skill | 135k | today | Apache-2.0 | A | 113 | Codex |
| playwright-climicrosoft/playwright | Skill | 100k | today | Apache-2.0 | A | 19 | Claude Code |
| browser-automationopenclaw/openclaw | Skill | 394k | today | MIT | A | 36 | Claude Code |
| local-ai-agentsmicrosoft/ai-agents-for-beginners | Skill | 80k | 6d ago | MIT | A | 200 | Claude Code, Codex |
| next-cache-components-adoptionvercel/next.js | Skill | 143k | today | MIT | A | 95 | Claude Code |
| chat-pet-sprite-creationmicrosoft/vscode | Skill | 195k | today | MIT | A | 53 | Claude Code, Codex |