bobmatnyc

bad-example-skill

ANTI-PATTERN - Example showing violations of self-containment (DO NOT COPY)

bobmatnyc 73 20 Updated 8mo ago

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npx skillscat add bobmatnyc/claude-mpm-skills/bad-example-skill

Install via the SkillsCat registry.

About this skill

This skill demonstrates an anti-pattern example showing violations of self-containment principles in AI agent skill development. It illustrates improper use of relative path dependencies and missing essential content that breaks when deployed in flat directory structures. Developers should reference this example to understand what not to do when creating independently deployable skills.

SKILL.md

⚠️ BAD EXAMPLE - Interdependent Skill (Anti-Pattern)

WARNING: This is an ANTI-PATTERN example showing what NOT to do.

DO NOT COPY THIS STRUCTURE. See good-self-contained-skill for correct approach.


❌ VIOLATION #1: Relative Path Dependencies

## Related Documentation

For setup instructions, see [../setup-skill/SKILL.md](../setup-skill/SKILL.md)

For testing patterns, see:
- [../../testing/pytest-patterns/](../../testing/pytest-patterns/)
- [../../testing/test-utils/](../../testing/test-utils/)

Database integration: [../../data/database-skill/](../../data/database-skill/)

Why This is Wrong:

  • ❌ Uses relative paths (../, ../../)
  • ❌ Assumes hierarchical directory structure
  • ❌ Breaks in flat deployment (~/.claude/skills/)
  • ❌ Links break when skill deployed standalone

Correct Approach:

## Complementary Skills

Consider these related skills (if deployed):

- **setup-skill**: Installation and configuration patterns
- **pytest-patterns**: Testing framework and fixtures
- **database-skill**: Database integration patterns

*Note: All skills are independently deployable.*

❌ VIOLATION #2: Missing Essential Content

## Testing

This skill uses pytest for testing.

**See pytest-patterns skill for all testing code.**

To write tests for this framework, install pytest-patterns skill
and refer to its documentation.

Why This is Wrong:

  • ❌ No actual testing patterns included
  • ❌ Requires user to have another skill
  • ❌ Skill is incomplete without other skills
  • ❌ "See other skill" instead of inlining

Correct Approach:

## Testing (Self-Contained)

**Essential pytest pattern** (inlined):

```python
import pytest
from example_framework.testing import TestClient

@pytest.fixture
def client():
    """Test client fixture."""
    return TestClient(app)

def test_home_route(client):
    """Test homepage."""
    response = client.get("/")
    assert response.status_code == 200
    assert response.json() == {"message": "Hello"}

Advanced fixtures (if pytest-patterns skill deployed):

  • Parametrized fixtures
  • Database session fixtures
  • Mock fixtures

See pytest-patterns skill for comprehensive patterns.


---

## ❌ VIOLATION #3: Hard Skill Dependencies

```markdown
## Prerequisites

**Required Skills**:
1. **setup-skill** - Must be installed first
2. **database-skill** - Required for database operations
3. **pytest-patterns** - Required for testing

Install all required skills before using this skill:
```bash
claude-code skills add setup-skill database-skill pytest-patterns

This skill will not work without these dependencies.


**Why This is Wrong**:
- ❌ Lists other skills as "Required"
- ❌ Skill doesn't work standalone
- ❌ Creates deployment coupling
- ❌ Violates self-containment principle

**Correct Approach**:
```markdown
## Prerequisites

**External Dependencies**:
```bash
pip install example-framework pytest sqlalchemy

Complementary Skills

When using this skill, consider (if deployed):

  • setup-skill: Advanced configuration patterns (optional)
  • database-skill: ORM patterns and optimization (optional)
  • pytest-patterns: Testing enhancements (optional)

This skill is fully functional independently.


---

## ❌ VIOLATION #4: Cross-Skill Imports

```python
"""
Bad example - importing from other skills.
"""

# ❌ DON'T DO THIS
from skills.database_skill import get_db_session
from skills.pytest_patterns import fixture_factory
from ..shared.utils import validate_input

# Using imported patterns
@app.route("/users")
def create_user(data):
    # Requires database-skill to be installed
    with get_db_session() as session:
        user = User(**data)
        session.add(user)
        return user.to_dict()

Why This is Wrong:

  • ❌ Imports from other skills
  • ❌ Code won't run without other skills
  • ❌ Creates runtime dependencies
  • ❌ Violates Python module boundaries

Correct Approach:

"""
Good example - self-contained implementation.
"""
from contextlib import contextmanager

# ✅ Include pattern directly in this skill
@contextmanager
def get_db_session():
    """Database session context manager (self-contained)."""
    db = SessionLocal()
    try:
        yield db
        db.commit()
    except Exception:
        db.rollback()
        raise
    finally:
        db.close()

@app.route("/users")
def create_user(data):
    # Works independently
    with get_db_session() as session:
        user = User(**data)
        session.add(user)
        return user.to_dict()

❌ VIOLATION #5: Hierarchical Directory Assumptions

## Project Structure

This skill is located in:

toolchains/python/frameworks/bad-example-skill/


**Navigate to parent directories for related skills**:
- `../` - Other framework skills
- `../../testing/` - Testing skills
- `../../data/` - Database skills

**All skills in `toolchains/python/frameworks/` are related to this skill.**

Why This is Wrong:

  • ❌ Assumes specific directory structure
  • ❌ Navigation instructions using relative paths
  • ❌ Won't work in flat deployment
  • ❌ Confuses deployment location with skill relationships

Correct Approach:

## Related Skills

**Complementary Python Framework Skills** (informational):

- **fastapi-patterns**: Web framework patterns
- **django-patterns**: Full-stack framework patterns
- **flask-patterns**: Micro-framework patterns

**Testing Skills**:
- **pytest-patterns**: Testing framework
- **test-driven-development**: TDD workflow

*Note: Skills are independently deployable. Directory structure may vary.*

❌ VIOLATION #6: Incomplete Examples

# Database setup
# (See database-skill for complete implementation)

class User(db.Model):
    # ... see database-skill for model definition ...
    pass

# Testing
# (See pytest-patterns for test examples)

def test_user():
    # ... see pytest-patterns for fixtures ...
    pass

# Deployment
# (See deployment-skill for production setup)

Why This is Wrong:

  • ❌ Examples are fragments, not complete code
  • ❌ "See other skill" instead of showing code
  • ❌ Users can't copy-paste and run
  • ❌ Skill provides no actual implementation guidance

Correct Approach:

# Complete database model (self-contained)
from sqlalchemy import Column, Integer, String
from sqlalchemy.ext.declarative import declarative_base

Base = declarative_base()

class User(Base):
    """User model - complete implementation."""
    __tablename__ = "users"

    id = Column(Integer, primary_key=True)
    username = Column(String(80), unique=True, nullable=False)
    email = Column(String(120), unique=True, nullable=False)

    def to_dict(self):
        return {
            "id": self.id,
            "username": self.username,
            "email": self.email
        }

# Complete test example (self-contained)
import pytest
from example_framework.testing import TestClient

@pytest.fixture
def client():
    return TestClient(app)

def test_create_user(client):
    """Test user creation - complete working test."""
    response = client.post("/users", json={
        "username": "testuser",
        "email": "test@example.com"
    })
    assert response.status_code == 201
    assert response.json()["username"] == "testuser"

# Complete deployment example (self-contained)
import os

class ProductionConfig:
    DEBUG = False
    SECRET_KEY = os.getenv("SECRET_KEY")
    DATABASE_URL = os.getenv("DATABASE_URL")

app = App(config=ProductionConfig())

# Run with: gunicorn -w 4 app:app

❌ VIOLATION #7: References Directory with Cross-Skill Paths

bad-example-skill/
├── SKILL.md
├── metadata.json
└── references/
    ├── testing.md          # Contains: ../../pytest-patterns/
    ├── database.md         # Contains: ../../database-skill/
    └── deployment.md       # Contains: ../../../universal/deployment/

references/testing.md contains:

# Testing Patterns

For complete testing patterns, see:
- [Pytest Patterns](../../pytest-patterns/SKILL.md)
- [TDD Workflow](../../../universal/testing/test-driven-development/)

Refer to those skills for all testing code.

Why This is Wrong:

  • ❌ References directory has cross-skill paths
  • ❌ Progressive disclosure leads outside skill
  • ❌ Breaks in flat deployment
  • ❌ References aren't self-contained

Correct Approach:

good-example-skill/
├── SKILL.md
├── metadata.json
└── references/
    ├── advanced-patterns.md    # All about THIS skill
    ├── api-reference.md        # THIS skill's API
    └── examples.md             # THIS skill's examples

references/advanced-patterns.md should contain:

# Advanced Testing Patterns

**Advanced pytest fixtures** (this skill):

```python
# Parametrized test fixture
@pytest.fixture(params=["value1", "value2"])
def data_variants(request):
    return request.param

def test_with_variants(data_variants):
    # Test with multiple data variants
    assert process(data_variants) is not None

Further enhancements (if pytest-patterns deployed):

  • Fixture factories
  • Custom markers
  • Plugin integration

See pytest-patterns skill for comprehensive advanced patterns.


---

## ❌ VIOLATION #8: metadata.json with Skill Dependencies

```json
{
  "name": "bad-example-skill",
  "version": "1.0.0",
  "requires": [
    "setup-skill",
    "database-skill",
    "pytest-patterns"
  ],
  "self_contained": false,
  "dependencies": ["example-framework"],
  "notes": [
    "This skill requires setup-skill to be installed first",
    "Must deploy with database-skill for database operations",
    "Won't work without pytest-patterns for testing"
  ]
}

Why This is Wrong:

  • ❌ Lists other skills in "requires" field
  • "self_contained": false
  • ❌ Notes say skill won't work without others
  • ❌ Creates deployment coupling

Correct Approach:

{
  "name": "good-example-skill",
  "version": "1.0.0",
  "requires": [],
  "self_contained": true,
  "dependencies": ["example-framework", "pytest", "sqlalchemy"],
  "complementary_skills": [
    "setup-skill",
    "database-skill",
    "pytest-patterns"
  ],
  "notes": [
    "This skill is fully self-contained and works independently",
    "All essential patterns are inlined",
    "Complementary skills provide optional enhancements"
  ]
}

Summary of Violations

Violation Example Impact
Relative Paths ../../other-skill/ Breaks in flat deployment
Missing Content "See other skill for X" Incomplete, not self-sufficient
Hard Dependencies "Requires other-skill" Can't deploy standalone
Cross-Skill Imports from skills.other import Runtime dependency
Hierarchical Assumptions "Navigate to parent dir" Location-dependent
Incomplete Examples Code fragments only Not usable
References Cross-Skill references/ has ../ Progressive disclosure broken
Metadata Dependencies "requires": ["skill"] Deployment coupling

How to Fix These Violations

Step 1: Remove All Relative Paths

# Find violations
grep -r "\.\\./" bad-example-skill/

# Remove them - use skill names instead
# ❌ [skill](../../skill/SKILL.md)
# ✅ skill (if deployed)

Step 2: Inline Essential Content

# Before (wrong):
## Testing
See pytest-patterns skill for all testing code.

# After (correct):
## Testing (Self-Contained)

**Essential pattern** (inlined):
[20-50 lines of actual testing code]

**Advanced patterns** (if pytest-patterns deployed):
- Feature list

*See pytest-patterns for comprehensive guide.*

Step 3: Remove Hard Dependencies

# Before (wrong):
**Required Skills**: pytest-patterns, database-skill

# After (correct):
**Complementary Skills** (optional):
- pytest-patterns: Testing enhancements
- database-skill: ORM optimization

Step 4: Make Imports Self-Contained

# Before (wrong):
from skills.database import get_db_session

# After (correct):
@contextmanager
def get_db_session():
    """Inlined pattern."""
    # Implementation here

Step 5: Update metadata.json

// Before (wrong):
{
  "requires": ["other-skill"],
  "self_contained": false
}

// After (correct):
{
  "requires": [],
  "self_contained": true,
  "complementary_skills": ["other-skill"]
}

Verification

After fixing, verify self-containment:

# Should return empty (no violations)
grep -r "\.\\./" skill-name/
grep -r "from skills\." skill-name/
grep -i "requires.*skill" skill-name/SKILL.md

# Isolation test
cp -r skill-name /tmp/skill-test/
cd /tmp/skill-test/skill-name
cat SKILL.md  # Should be complete and useful

# Metadata check
cat metadata.json | jq '.requires'  # Should be [] or external packages only

See Good Example Instead

DO NOT USE THIS EXAMPLE AS A TEMPLATE

Instead, see:


Remember: This example shows what NOT to do. Always ensure your skills are self-contained!