Avoid dependency hell for Claude SKILLs

Claude Code is probably the first general-purpose AI agent humanity has created. The real breakthrough is that Claude Code can write precise code to “act” on its “thoughts”. A key enabler of this breakthrough is Agent SKILLs, i.e., reusable packages of instructions, reference materials, and executable scripts that turn Claude into a consistently powerful specialist.

The community is going wild about Claude SKILLs on x:

“Claude Skills is the best feature I've ever used.” — @godofprompt

“if you're not arming Claude with Skills you're missing out on 90% of it's power.” — @boringmarketer

“Don't sleep on Skills. Skills is easily one of the most effective ways to steer Claude Code.” — @omarsar0

SKILLs eliminate repetitive prompting, solve context rot, and unlock deterministic, tool-equipped workflows that feel like having a team of expert agents.

What Is a Claude Agent SKILL?

A Claude agent SKILL is a structured, reusable package stored in your project's .claude/skills/ folder. It combines the following:

• Precise instructions defining the agent's role and step-by-step process
• Reference files (style guides, examples, brand voice)
• Executable scripts (Python, Node.js, Bash) for reliable, deterministic actions

Here are examples of some popular SKILLs:

• Frontend critique: Analyzes designs and suggests polished improvements
• PDF extraction: Reliably pulls text, tables, and metadata
• Data analysis: Processes CSVs with pandas for insights and visualizations
• Web scraping: Uses Playwright or BeautifulSoup for structured data collection
• UTM campaign automation: Generates tracked links and reports performance

Users frequently ask Claude Code itself to generate new SKILLs, then fine-tune them manually—making iteration incredibly fast.

Beyond Prompts: The Power of Scripts

Top-tier Claude agent SKILLs go far beyond instructions. They include scripts for tasks that demand consistency.

For instance, a simple prompt to “extract data from this PDF” can hallucinate or miss tables. A SKILL with a Python script using pypdf or PyMuPDF guarantees accurate, repeatable results every time.

Other common scripted SKILLs include the following:

• Image processing with Pillow or OpenCV
• API interactions with custom authentication flows
• Automated testing with pytest
• Deployment scripts for Vercel/Netlify

Claude Code can execute these SKILL scripts autonomously.

The Dependency Challenge

SKILL scripts, especially Python or JavaScript, often require 3rd party libraries and dependencies. Claude Code is smart. When it sees the ModuleNotFoundError, it reasons, and runs pip install or npm install itself. That's magical for prototyping.

But on your host machine, this rapidly creates problems:

• Global environment bloat
• Version conflicts between projects
• Security concerns from dynamic installs
• Non-reproducible setups

<div style="display: flex; justify-content: center;"> <blockquote class="twitter-tweet”> <p lang="en” dir="ltr”>The best minds of my generation are thinking about how to install Python.</p> — Santiago Víquez (@santiviquez) <a href="https://twitter.com/santiviquez/status/1676677829751177219”>July 6, 2023</a> </blockquote> <script async src="https://platform.twitter.com/widgets.js” charset="utf-8”></script> </div>

Quote of Chris Albon asking: “What is ‘the right way’ to install Python on a new M2 MacBook? I assume it isn't the system Python3 right? Maybe Homebrew?"

For serious SKILL based agents, you need isolation.

The Clean Solution: Docker Sandboxes

@Docker Sandboxes (experimental in Docker Desktop 4.50+) was built exactly for agents like Claude Code. It lets you run Claude with full autonomy while keeping your host machine pristine.

One command launches everything safely:

docker sandbox run claude

*Try out VibeKeys