PTENES
MODULE 1.1

🧩 What Is a Skill

Understand the fundamental concept: a skill is a folder with a SKILL.md file that packages reusable knowledge in Markdown—no coding or complex setup required.

6
Topics
~20
Minutes
Basic
Level
Theory
Type
📁 my-skill/ SKILL.md references/ SKILL.md name: description: — instructions — examples Claude runs the skill ① FOLDER ② INSTRUCTION ③ EXECUTION 🧩 Skill = Packaged Knowledge Markdown that Claude reads · no code · reusable HyperFrames Skill FOLDER + SKILL.md → ACTIVE KNOWLEDGE
1

📁 Folder + SKILL.md

A skill’s minimum structure is absolute: a folder with any name and a single file inside it called SKILL.md. That's all. Nothing else is required.

Main Concept

A skill is a folder. Inside it lives the SKILL.md — the only file Claude Code needs to load and run the defined behavior. Optionally, the folder can have a subfolder references/ with supporting files.

When Claude Code finds SKILL.md in the configured skills folder (~/.claude/skills/), it makes that skill available as a command /nome-da-skill.

Minimum structure for a skill
# directory tree
~/.claude/skills/
explainer-video/
SKILL.md # required
references/ # optional
pipeline.md
house-style.md
📦 Real example: video-explainer skill
Folder
~/.claude/skills/video-explicativo/
Root file
SKILL.md (required, single)
References
references/pipeline.md
references/house-style.md
Support scripts
scripts/narration-template.sh
scripts/composition-template.mjs
💡
The folder can have any name

The folder name becomes the command name. video-explicativo/ becomes /video-explicativo. Choose descriptive names without spaces—use hyphens.

Key concepts
📁
Folder
Skill unit
📄
SKILL.md
Only required item
📂
references/
Optional support
⚡
/nome-skill
Generated command
2

📦 Packaged knowledge

A skill isn’t an ephemeral prompt typed on the spot — it’s a reusable, tested, and versionable procedure. It’s knowledge you teach once and Claude applies whenever needed.

The fundamental difference

Think of a cooking recipe. You don’t reinvent the whole recipe every time you cook—you write it once, save it, and follow it. A skill is exactly that: a written, saved recipe you can reuse for any future “cooking session.”

The SKILL.md for the video-explicativo defines the complete video creation workflow: script → TTS narration → animated scenes → render → captions → CTA. This knowledge is packaged and ready for reuse.

Packaged knowledge lifecycle
1
You write once

Describe the procedure, rules of thumb, and quality standards in SKILL.md. It can take 30 minutes—or hours if it’s complex.

2
Claude learns automatically

Every time you invoke /video-explicativo, Claude loads the SKILL.md and follows the instructions — without you having to repeat anything.

3
Consistent result

The INEMA.CLUB video always has a palette #0D1321, voice pf_dora --speed 0.98, fade of 0.45s — because it is written in the skill.

4
Iterative evolution

When you discover something better (e.g., new LEAD or TAIL timing), edit SKILL.md once and all future videos will inherit the improvement.

⚠️
Knowledge in your head doesn’t scale

If the procedure exists only in your memory, each new session starts from scratch. You end up re-explaining the same workflow to Claude, making the same mistakes, and losing consistency. The skill eliminates this cost.

Key concepts
🔁
Reusable
Write once
📐
Consistent
Same result
🌱
Evolutionary
Always improve
🧠
Externalized
Out of memory
3

✍️ Markdown as instructions

The body of SKILL.md is plain Markdown. Claude interprets this text as execution instructions—not as documentation for people, but as commands it will follow.

Minimal SKILL.md (canonical format)
# ~/.claude/skills/video-explicativo/SKILL.md
name: explainer-video
description: Create complete explanatory videos in PT-BR
             (HTML→MP4 via HyperFrames) from a
             subject...

# Workflow
1. Read the topic provided by the user
2. Create the script in PT-BR (3-5 scenes)
3. Generate narration with pf_dora --speed 0.98
4. Build dark premium HTML scenes
5. Render 16:9 and 9:16

# Golden rules
- Palette: bg #0D1321, panel #1D2D44
- LEAD=0.5 TAIL=0.9 FADE=0.45
- Always PT-BR, never English in the narration
Front matter + Body

SKILL.md has two parts: the front-matter (header with name: e description:) e o body — Markdown sections with the full procedure. Claude Code uses the front matter to list and activate the skill, and the body to run it.

✓ Best practices in SKILL.md
  • ✓ Write in the imperative: "Read…", "Create…", "Generate…"
  • ✓ Use sections with ## to separate flow and rules
  • ✓ Include exact values: --speed 0.98, not "slow speed"
  • ✓ Mark non-negotiables with "NEVER" or "ALWAYS"
✗ Common errors
  • ✗ Don’t be vague: “make a good video” doesn’t work
  • ✗ Don’t omit the front matter (name: and description:)
  • ✗ Don’t write like passive technical documentation
  • ✗ Don't put execution instructions in reference files
💡
SKILL.md is read in full before running

When you type /video-explicativo, Claude Code injects the full contents of the SKILL.md into the session context before responding. That's why instructions at the beginning and the end carry the same weight.

Key concepts
📝
Front matter
name + description
📋
Markdown body
Imperative instructions
🎯
Exact values
No ambiguity
🔒
Non-negotiables
ALWAYS / NEVER
4

⚖️ Skill vs. one-off prompt

A one-off prompt works once, in that session, with that context. A skill is durable, automatic, and reproducible — the difference between a sticky note and an operations manual.

Skill vs. One-Off Prompt
Aspect Skill Standalone prompt
Durability Permanent (file) Ephemeral (ends with the session)
Activation Automatic via /nome Manual, you type everything
Consistency Identical every time Varies based on memory
Maintenance Edit the file Rewrite the entire prompt
Sharing Git, zip, folder copy Manual Ctrl+C / Ctrl+V
✓ Use a skill when...
  • ✓ You’ll repeat the same type of task many times
  • ✓ Need absolute consistency (branding, format)
  • ✓ You want to share the procedure with others
  • ✓ The flow has more than 3 steps or critical rules
✗ A standalone prompt is enough when...
  • ✗ It’s a single question; it won’t come up again
  • ✗ The context changes completely each time
  • ✗ Quick exploration, no reproduction needed
  • ✗ One-step task with no specific parameters
💡
3× test: if you'll do it 3 times, make it a skill

A simple rule of thumb: if you can imagine doing the same task 3 or more times, the time spent writing the SKILL.md pays off by the fourth run. Fewer than 3, and a one-off prompt is faster.

Key concepts
♾️
Durable
File persists
🤖
Automatic
No retyping
💨
Ephemeral
Prompt disappears
3×
3x Rule
Positive ROI
5

🎯 Examples: video, code, UI

Skills cover any domain — not just video. This entire course was born from a skill (formato-curso). See the variety of options available.

This course grew out of a skill

Each page of this course was created by the skill formato-curso. It defines the components, premium dark CSS, module structure, and INEMA.CLUB quality standards—all in Markdown, with no JavaScript code.

The skill video-explicativo (which this course teaches) defines the HTML→MP4 workflow: palette #0D1321, voice pf_dora, timings LEAD=0.5 TAIL=0.9 FADE=0.45. Two domains, same structure: folder + SKILL.md.

Domain-specific skills
🎬
Explainer video

Script → TTS pf_dora → dark HTML scenes → MP4 render. Fixed 8-step workflow, palette #0D1321, 16:9 and 9:16 formats.

skill: video-explicativo
📄
Course pages

Generates HTML with Tailwind, futuristic SVGs, expandable topics, and modals. Defines all components and palettes for each track.

skill: formato-curso
🔍
Deep research

Fans out searches, verifies sources, and synthesizes a cited report. Research skill with adversarial verification.

skill: deep-research
⚙️
n8n workflows

Generates and validates n8n automation workflows with specific JavaScript coding patterns and node expressions.

skill: n8n-workflow-patterns
🎨
UI design

Create components and web pages with specific visual patterns, design tokens, and style guides.

skill: frontend-design
🔐
Security review

Audits code for vulnerabilities using OWASP checklists and security-specific standards.

skill: security-review
📊 Skills you probably already have installed
~/.claude/skills/
formato-curso/SKILL.md
explainer-video/SKILL.md
deep-research/SKILL.md
n8n-workflow-patterns/SKILL.md
How to list your skills
Type / in Claude Code
→ lists all active skills
→ each one = a folder
→ each folder = one SKILL.md
Key concepts
🎬
Video
HyperFrames
💻
Code
n8n, security
🎨
UI/Design
Web components
🔬
Research
Deep research
6

🚀 No coding required

A simple skill is just text. You don’t need to know JavaScript, Python, or any programming language to create powerful skills — Markdown is enough.

Markdown is a sufficient programming language

When you write “1. Read the topic. 2. Create a 3-scene script. 3. Use the pf_dora voice.” in SKILL.md, that é a program. Claude interprets natural language instructions with the same fidelity that a computer interprets code.

The skill video-explicativo has hundreds of precise instructions — timings, palettes, formats — and is entirely Markdown. Zero JavaScript in the main SKILL.md.

✅
Code is in the references, not in the skill

The folder references/ may contain scripts such as narration-template.sh e composition-template.mjs — but these are templates that Claude use as a template, not code that the skill runs directly. The skill provides instructions; the templates provide examples.

✓ A simple skill works like this
  • ✓ Create the folder and SKILL.md in 10 minutes
  • ✓ Write clear instructions in Portuguese
  • ✓ Test by calling /nome-da-skill in Claude Code
  • ✓ Iterate: edit SKILL.md as you learn
✗ Don't overcomplicate things unnecessarily
  • ✗ Don’t wait until you know how to program to get started
  • ✗ Don’t try to cover every use case at once
  • ✗ Don’t use complex YAML when Markdown will do
  • ✗ Don’t wait for the skill to be “perfect” before using it
💡
Start with 10 lines

The simplest skill possible: name: minha-skill, description: o que faz, and 3-5 steps in Markdown. Run, adjust, expand. The skill video-explicativo that you will learn in this course started this way — and today it has references, scripts, and hundreds of rules.

Examples of 10-line skills
📧
Email response

Tone, format, and default signature instructions. 8 lines. Saves 5 minutes per email.

📊
Weekly report

Section templates, required metrics, executive tone. 12 lines. Total consistency.

🐛
Bug debugging

Hypothesis checklist, diagnostic format, fix commit standard. 10 lines.

Key concepts
📝
Markdown only
No code
⏱️
10 minutes
To get started
🔄
Iterate
Always improve
🎯
Active imperfection
Better than missing

📋 Module 1.1 summary

What you learned
  • ✓ Skill = folder + SKILL.md — minimal and sufficient structure
  • ✓ Packaged knowledge: write once, reuse forever
  • ✓ The body of SKILL.md is Markdown that Claude executes as instructions
  • ✓ A skill is durable + automatic; a one-off prompt is temporary + manual
  • ✓ Domains: video, code, UI, research—this course was born from a skill
  • ✓ Start with 10 lines of Markdown — no code needed
Next module
1.2
📝 SKILL.md anatomy
Dissect the SKILL.md file line by line: front matter, required sections, activation triggers, non-negotiable rules, and the role of the folder references/.
Go to module 1.2 →