legacy-code-summarizer

Legacy Code Summarizer

Analyze and summarize legacy codebases to quickly understand their structure, quality, and improvement opportunities.

Core Capabilities

This skill helps understand legacy code by:

1. Mapping architecture - Identify key components, layers, and relationships
2. Analyzing dependencies - Understand module coupling and import patterns
3. Detecting quality issues - Find code smells, technical debt, and outdated patterns
4. Assessing test coverage - Identify testing gaps and untested code
5. Generating documentation - Create actionable summaries for teams

Code Analysis Workflow

Step 1: Survey the Codebase

Get an overview of the project structure and size.

Initial Questions:

• What programming language(s)?
• What is the project structure?
• How large is the codebase?
• What frameworks/libraries are used?
• Is there existing documentation?

Commands to Run:

# Count lines of code
find . -name "*.py" | xargs wc -l | tail -1  # Python
find . -name "*.java" | xargs wc -l | tail -1  # Java

# Count files
find . -name "*.py" | wc -l
find . -name "*.java" | wc -l

# Directory structure
tree -L 3 -I '__pycache__|node_modules|target|build'

# Or without tree command
find . -type d -not -path '*/\.*' | head -20

Identify Project Type:

• Web application (frontend/backend)
• CLI tool
• Library/framework
• Microservice
• Monolith
• Desktop application

Step 2: Identify Entry Points

Find where execution starts and main workflows.

Common Entry Points:

Python:

# Find main entry points
grep -r "if __name__ == '__main__':" --include="*.py"

# Find Flask/Django apps
grep -r "app = Flask\|application = " --include="*.py"
grep -r "INSTALLED_APPS\|MIDDLEWARE" --include="*.py"

# Find CLI entry points (setup.py, pyproject.toml)
grep -A 10 "entry_points\|console_scripts" setup.py pyproject.toml

Java:

# Find main methods
grep -r "public static void main" --include="*.java"

# Find Spring Boot applications
grep -r "@SpringBootApplication" --include="*.java"

# Find servlets
grep -r "extends HttpServlet\|@WebServlet" --include="*.java"