/dignified-python

name: dignified-python
description:
  Opinionated production Python standards with automatic version detection (3.10-3.13). Use when
  writing, reviewing, or refactoring Python in repos that want modern type syntax, explicit
  condition checks where practical, pathlib operations, interface guidance, and pragmatic
  production patterns.
references:
  - dignified-python-core
  - cli-patterns
  - versions/python-3.10
  - versions/python-3.11
  - versions/python-3.12
  - versions/python-3.13
  - references/advanced/api-design
  - references/advanced/exception-handling
  - references/advanced/interfaces
  - references/advanced/typing-advanced

Dignified Python

Opinionated Python guidance for writing clean, maintainable, modern Python code (versions 3.10-3.13).

When to Use This Skill

Auto-invoke when users ask about:

• "make this pythonic" / "is this good python"
• "type hints" / "type annotations" / "typing"
• "LBYL vs EAFP" / "exception handling"
• "pathlib vs os.path" / "path operations"
• "CLI patterns" / "click usage"
• "code review" / "improve this code"
• Any Python code quality or standards question

**Note**: This skill is **general-purpose Python style guidance**, not Dagster-specific. It captures one explicit, LBYL-leaning set of conventions; project conventions can override it when needed.

When to Use This Skill vs. Others

| User Need | Use This Skill | Alternative Skill | | ---------------------------- | --------------------------- | ------------------------- | | "make this pythonic" | ✅ Yes - Python standards | | | "is this good python" | ✅ Yes - code quality | | | "type hints" | ✅ Yes - typing guidance | | | "LBYL vs EAFP" | ✅ Yes - exception patterns | | | "pathlib vs os.path" | ✅ Yes - path handling | | | "best practices for dagster" | ❌ No | `/dagster-best-practices` | | "implement X pipeline" | ❌ No | `/dg` for implementation | | "which integration to use" | ❌ No | `/dagster-expert` | | "CLI argument parsing" | ✅ Yes - CLI patterns | |

Core Knowledge (ALWAYS Loaded)

@dignified-python-core.md

Version Detection

**Identify the project's minimum Python version** by checking (in order):

1. `pyproject.toml` - Look for `requires-python` field (e.g., `requires-python = ">=3.12"`) 2. `setup.py` or `setup.cfg` - Look for `python_requires` 3. `.python-version` file - Contains version like `3.12` or `3.12.0` 4. Default to Python 3.12 if no version specifier found

**Once identified, load the appropriate version-specific file:**

• Python 3.10: Load `versions/python-3.10.md`
• Python 3.11: Load `versions/python-3.11.md`
• Python 3.12: Load `versions/python-3.12.md`
• Python 3.13: Load `versions/python-3.13.md`

Conditional Loading (Load Based on Task Patterns)

Core files above cover 80%+ of Python code patterns. Only load these additional files when you detect specific patterns:

Pattern detection examples:

• If task mentions "click" or "CLI" -> Load `cli-patterns.md`
• If task mentions "subprocess" -> Load `subprocess.md`

Reference Documentation Structure

This skill's reference material is organized by topic:

Core References

• **`dignified-python-core.md`** - Essential standards (always loaded)
• **`cli-patterns.md`** - Command-line interface patterns (click, argparse)

Version-Specific References (`versions/`)

• **`python-3.10.md`** - Features available in Python 3.10+
• **`python-3.11.md`** - Features available in Python 3.11+
• **`python-3.12.md`** - Features available in Python 3.12+
• **`python-3.13.md`** - Features available in Python 3.13+

Advanced Topics (`references/advanced/`)

• **`exception-handling.md`** - LBYL patterns, error boundaries
• **`interfaces.md`** - ABC and Protocol patterns
• **`typing-advanced.md`** - Advanced typing patterns
• **`api-design.md`** - API design principles

When to Read Each Reference Document

`references/advanced/exception-handling.md`

**Read when**:

• Writing try/except blocks
• Wrapping third-party APIs that may raise
• Seeing or writing `from e` or `from None`
• Unsure if LBYL alternative exists

`references/advanced/interfaces.md`

**Read when**:

• Creating ABC or Protocol classes
• Writing @abstractmethod decorators
• Designing gateway layer interfaces
• Choosing between ABC and Protocol

`references/advanced/typing-advanced.md`

**Read when**:

• Using typing.cast()
• Creating Literal type aliases
• Narrowing types in conditional blocks

`references/module-design.md`

**Read when**:

• Creating new Python modules
• Adding module-level code (beyond simple constants)
• Using @cache decorator at module level
• Seeing Path() or computation at module level
• Considering inline imports

`references/advanced/api-design.md`

**Read when**:

• Adding default parameter values to functions
• Defining functions with 5 or more parameters
• Using ThreadPoolExecutor.submit()
• Reviewing function signatures

`references/checklists.md`

**Read when**:

• Final review before committing Python code
• Unsure if you've followed all rules
• Need a quick lookup of requirements

How to Use This Skill

1. **Core knowledge** is loaded automatically (defaults, pathlib, imports, anti-patterns) 2. **Version detection** happens once - identify the minimum Python version and load the appropriate version file 3. **Reference documents** are loaded on-demand based on the triggers above 4. **Additional patterns** may require extra loading (CLI patterns, subprocess) 5. **Each file is self-contained** with complete guidance for its domain