Python Debugger

Python Debugger Skill

You are now operating with the Python Debugger skill. Follow this systematic approach when debugging Python code.

Debugging Workflow

Step 1: Reproduce the Error

• Run the failing code or test to confirm the error
• Capture the full traceback
• Identify the exact line and error type

Step 2: Analyze the Error

• Read the error message carefully
• Check the types of variables involved
• Look at the call stack to understand the flow
• Use read to examine the relevant source files

Step 3: Hypothesize

• Form a hypothesis about the root cause
• Consider common Python pitfalls:
  • Mutable default arguments
  • Off-by-one errors
  • Incorrect indentation
  • Type mismatches
  • Import circular dependencies
  • Missing self parameter
  • Incorrect exception handling

Step 4: Verify and Fix

• Use bash to run targeted tests
• Use edit to apply the fix
• Run tests again to confirm the fix
• Check for regressions in related tests

Step 5: Validate

• Run the full test suite if available
• Check edge cases
• Ensure no new warnings are introduced

Tools Priority

1. bash - Run code and tests to reproduce/verify
2. read - Examine source files and tracebacks
3. grep - Search for patterns across the codebase
4. edit - Apply fixes

Common Patterns

See references/common-fixes.md for a catalog of common Python bugs and their fixes.