How to Use Claude for Debugging Python
The exact prompt, setup, and codes to get great results.
The Problem
Python's dynamic typing and silent failures make bugs hard to catch. A function returns None instead of a value, a dictionary key is missing, or an import fails at runtime.
The Prompt (Copy & Paste)
Debug this Python code. Python version: [VERSION] Libraries: [LIST KEY PACKAGES] What should happen: [EXPECTED] What actually happens: [ACTUAL] Traceback: ``` [PASTE FULL TRACEBACK] ``` Code: ```python [PASTE CODE] ``` Steps: 1. Read the traceback and identify the exact failure point 2. Explain the root cause (not "you have a bug on line X") 3. Show the minimal fix 4. Check for related issues in the surrounding code (off-by-one, type mismatches, missing edge cases) 5. Suggest one defensive coding pattern that would have caught this earlier
Replace the [BRACKETED] placeholders with your specific details.
What You Get
A clear diagnosis that goes beyond 'line X is wrong.' Claude explains the underlying Python behavior causing the issue and suggests defensive patterns to prevent similar bugs.
Prompt Codes That Help
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