Python Design
mindfold-ai/Trellis
Python design patterns for CLI scripts and utilities — type-first development, deep modules, complexity management, and red flags.
Python design patterns including KISS, Separation of Concerns, Single Responsibility, and composition over inheritance.
Install Python Design Patterns
$ npx skills add wshobson/agents --skill python-design-patterns -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install wshobson/agents python-design-patterns --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .claude/skills && cp -r skills-src/plugins/python-development/skills/python-design-patterns .claude/skills/python-design-patterns && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "python-design-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/python-development/skills/python-design-patterns into .claude/skills/python-design-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "python-design-patterns", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/wshobson/agents/tree/main/plugins/python-development/skills/python-design-patternsType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add wshobson/agents --skill python-design-patterns -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install wshobson/agents python-design-patterns --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .agents/skills && cp -r skills-src/plugins/python-development/skills/python-design-patterns .agents/skills/python-design-patterns && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "python-design-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/python-development/skills/python-design-patterns into .agents/skills/python-design-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "python-design-patterns", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add wshobson/agents --skill python-design-patterns -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install wshobson/agents python-design-patterns --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/plugins/python-development/skills/python-design-patterns .cursor/skills/python-design-patterns && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "python-design-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/python-development/skills/python-design-patterns into .cursor/skills/python-design-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "python-design-patterns", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/wshobson/agents.git --path plugins/python-development/skills/python-design-patterns--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add wshobson/agents --skill python-design-patterns -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install wshobson/agents python-design-patterns --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/plugins/python-development/skills/python-design-patterns .gemini/skills/python-design-patterns && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "python-design-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/python-development/skills/python-design-patterns into .gemini/skills/python-design-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "python-design-patterns", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install wshobson/agents python-design-patternsInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add wshobson/agents --skill python-design-patterns -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .github/skills && cp -r skills-src/plugins/python-development/skills/python-design-patterns .github/skills/python-design-patterns && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "python-design-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/python-development/skills/python-design-patterns into .github/skills/python-design-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "python-design-patterns", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add wshobson/agents --skill python-design-patterns -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install wshobson/agents python-design-patterns --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/wshobson/agents.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/plugins/python-development/skills/python-design-patterns .opencode/skills/python-design-patterns && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "python-design-patterns" agent skill from https://github.com/wshobson/agents/tree/main/plugins/python-development/skills/python-design-patterns into .opencode/skills/python-design-patterns/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "python-design-patterns", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
python-design-patterns- GitHub stars
- 40k
- Token cost
- ~1.2k tokens
- SKILL.md length
- 526 words
- Files
- 2 (incl. references)
- Skills in repo
- 142
- Repo updated
- First seen
- Licence
- MIT
At a glance
Python design patterns including KISS, Separation of Concerns, Single Responsibility, and composition over inheritance.
- Works in 4 steps: KISS (Keep It Simple) → Single Responsibility (SRP) → Composition Over Inheritance → …
- Designing a new service
- SKILL.md covers When to Use This Skill, Core Concepts, Quick Start and Detailed patterns and worked…, plus 3 more sections
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Python Design Patterns is an agent skill from wshobson/agents. Python design patterns including KISS, Separation of Concerns, Single Responsibility, and composition over inheritance. Use this skill when designing a new service or component from scratch and choosing how to layer responsibilities, when refactoring a God class or monolithic function that has grown too large, when deciding whether to add a new abstraction or live with duplication, when evaluating a pull request for structural issues like tight coupling or leaking internal types, when choosing between inheritance…
Its SKILL.md is about 1.2k tokens, which your agent loads only when the skill is triggered. The skill folder holds 2 other files, including reference files (for example `references/details.md`).
It sits in Development, covering Design patterns and Refactoring. It works with Python. The repository describes itself as: Multi-harness agentic plugin marketplace for Claude Code, Codex, Cursor, OpenCode, GitHub Copilot, Google Antigravity, and Pi. The licence is MIT.
When your agent uses it
- Designing a new service
- Component from scratch and choosing how to layer responsibilities
- Refactoring a God class
- Monolithic function that has grown too large
Example prompts
- “/python-design-patterns”
Requirements
- Python 3
Workflow steps
4 steps, taken from the step headings in SKILL.md.
What it can do on your machine
Read from SKILL.md and the folder at commit 46891e7. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md (its code samples are python).
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Python Design Patterns loads about 1.2k tokens when it runs, and up to ~3.9k if it reads all its reference files. Until then it costs about 168 tokens; SKILL.md has 526 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
The full file from wshobson/agents at commit 46891e7, republished under its MIT licence (© wshobson). 526 words, ~1,181 tokens.
Download SKILL.mdSave it as
.claude/skills/python-design-patterns/SKILL.md (or your agent's skills folder). This skill also uses 1 other file; get the full folder from GitHub.- name
- python-design-patterns
- description
- Python design patterns including KISS, Separation of Concerns, Single Responsibility, and composition over inheritance. Use this skill when designing a new service or component from scratch and choosing how to layer responsibilities, when refactoring a God class or monolithic function that has grown too large, when deciding whether to add a new abstraction or live with duplication, when evaluating a pull request for structural issues like tight coupling or leaking internal types, when choosing between inheritance and composition for a new class hierarchy, or when a codebase is becoming hard to test because of entangled I/O and business logic.
Python Design Patterns
Write maintainable Python code using fundamental design principles. These patterns help you build systems that are easy to understand, test, and modify.
When to Use This Skill
- Designing new components or services
- Refactoring complex or tangled code
- Deciding whether to create an abstraction
- Choosing between inheritance and composition
- Evaluating code complexity and coupling
- Planning modular architectures
Core Concepts
1. KISS (Keep It Simple)
Choose the simplest solution that works. Complexity must be justified by concrete requirements.
2. Single Responsibility (SRP)
Each unit should have one reason to change. Separate concerns into focused components.
3. Composition Over Inheritance
Build behavior by combining objects, not extending classes.
4. Rule of Three
Wait until you have three instances before abstracting. Duplication is often better than premature abstraction.
Quick Start
# Simple beats clever
# Instead of a factory/registry pattern:
FORMATTERS = {"json": JsonFormatter, "csv": CsvFormatter}
def get_formatter(name: str) -> Formatter:
return FORMATTERS[name]()Detailed patterns and worked examples
Detailed pattern documentation lives in references/details.md. Read that file when the navigation tier above is insufficient.
Best Practices Summary
- Keep it simple - Choose the simplest solution that works
- Single responsibility - Each unit has one reason to change
- Separate concerns - Distinct layers with clear purposes
- Compose, don't inherit - Combine objects for flexibility
- Rule of three - Wait before abstracting
- Keep functions small - 20-50 lines (varies by complexity), one purpose
- Inject dependencies - Constructor injection for testability
- Delete before abstracting - Remove dead code, then consider patterns
- Test each layer - Isolated tests for each concern
- Explicit over clever - Readable code beats elegant code
Show full SKILL.md (284 more words)Show less
Troubleshooting
A class is growing and seems to have multiple responsibilities, but splitting it feels wrong. Apply the "reason to change" test: list every change that could require editing this class. If the list has items from different domains (e.g., HTTP parsing AND business rules AND formatting), split it. If all changes stem from the same domain concern, the class may be appropriately sized.
Injecting all dependencies through the constructor is producing constructors with 7+ parameters. This is a sign of too many responsibilities in one class, not a problem with dependency injection. Split the class into smaller units first, then each constructor naturally becomes smaller.
Composition is producing deeply nested wrapper objects that are hard to trace. Keep the composition shallow (2-3 levels). If wrapping is the only mechanism, consider whether a Protocol-based approach or simple function composition would be cleaner than a chain of decorator objects.
The rule of three says not to abstract yet, but the duplication is causing bugs when one copy is updated but not the other. Duplication that diverges in dangerous ways should be abstracted sooner. The rule of three is a heuristic, not a law. If the copies are already diverging incorrectly, extract immediately and add a test that exercises the shared behavior.
A service layer is importing from the API layer, breaking the dependency direction. This is a layering violation. The service layer must not import from handlers. Introduce a shared types/models layer that both can import from, keeping the dependency arrow pointing downward (API → Service → Repository).
Related Skills
- python-testing-patterns — Test each layer in isolation using the dependency injection structure established here
- python-project-structure — Organize modules and directory layout so layer boundaries are explicit from the start
© wshobson, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
SKILL.md and 1 other file (references) in plugins/python-development/skills/python-design-patterns of wshobson/agents.
- SKILL.md
- references/details.md
Open the folder on GitHubat commit 46891e7
Compare with similar skills
Python Design Patterns next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Python Design Patterns this skillwshobson/agents | 40k | — | ~1.2k | Automated safety check: Pass | MIT | |
| Python Designmindfold-ai/Trellis | 15k | — | ~4k | Automated safety check: Pass | AGPL-3.0 | |
| Py Rigmudrii/hermesd | 119 | — | ~6.3k | Automated safety check: Pass | MIT | |
| Python Architecturemicrosoft/apm | 4k | — | ~347 | Automated safety check: Pass | MIT | |
| Python Design Patternsaiskillstore/marketplace | 430 | 1 repos | ~3.1k | Automated safety check: Pass | None | |
| Swiftui View RefactorDimillian/Skills | 4k | 5 repos | ~2k | Automated safety check: Pass | MIT |
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Related
Works with
Categories
Questions about Python Design Patterns
What does Python Design Patterns do?
Python design patterns including KISS, Separation of Concerns, Single Responsibility, and composition over inheritance. Python Design Patterns is an agent skill from wshobson/agents. Python design patterns including KISS, Separation of Concerns, Single Responsibility, and composition over inheritance.
When should I use Python Design Patterns?
Python Design Patterns fits situations like: designing a new service; component from scratch and choosing how to layer responsibilities; refactoring a God class; monolithic function that has grown too large.
How do I install Python Design Patterns in Claude Code?
Run `npx skills add wshobson/agents --skill python-design-patterns -a claude-code`. Or copy the skill folder (plugins/python-development/skills/python-design-patterns in wshobson/agents) into .claude/skills/python-design-patterns in your project. Claude Code loads it when a task matches its description.
How do I install Python Design Patterns in Codex?
Run `npx skills add wshobson/agents --skill python-design-patterns -a codex`. Or copy the skill folder (plugins/python-development/skills/python-design-patterns in wshobson/agents) into .agents/skills/python-design-patterns in your project. Codex loads it when a task matches its description.
Can I use Python Design Patterns in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add wshobson/agents --skill python-design-patterns -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/python-design-patterns, .gemini/skills/python-design-patterns, .github/skills/python-design-patterns and .opencode/skills/python-design-patterns in your project.
What does Python Design Patterns need to run?
SKILL.md names no scripts, command-line tools or credentials: Python Design Patterns is instructions for the agent only. Our summary lists: Python 3.
Does Python Design Patterns access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Python Design Patterns safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Python Design Patterns use?
Python Design Patterns is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Python Design Patterns use?
About 1.2k tokens (SKILL.md is roughly 4.7k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full. Its references folder adds about 2.7k tokens, read only when the agent opens those files.
What are the alternatives to Python Design Patterns?
Skills that share tags, products or a category with Python Design Patterns: Python Design (mindfold-ai/Trellis, 15k stars), Py Rig (mudrii/hermesd, 119 stars), Python Architecture (microsoft/apm, 4k stars) and Python Design Patterns (aiskillstore/marketplace, 430 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Python Design Patterns?
wshobson (a GitHub user) maintains it in wshobson/agents, which has 40,254 GitHub stars. The repository holds 142 skills in this directory. The repository was last updated on October 5, 2026.
Source: wshobson/agents on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.