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SOFTWARE DEVELOPMENT

Claude for debugging python, done properly.

The tested prompt, the codes that help, and the setup software development pros run. Copy, adapt, ship.

One-time purchase. Lifetime updates. Works with Claude, Codex, and Gemini.
Why this needs a proper prompt

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.

Why Claude for this

Three reasons this actually lands.

The prompt, the codes, the fit. Each one on its own is a nice-to-have. Together, they change the workflow.

The prompt is the product.

One tested prompt, copy-paste ready. Rules baked in, placeholders marked, tone locked down. No prompt-engineering trial runs, no back-and-forth.

Codes that stack.

Prefix with REASON, V=2, REFINE for compound effects. Each code is a documented technique, not a magic word.

Built for the role.

Tuned for software development workflows. Not a generic template, and not another "you are a helpful assistant" hack.

Without the pattern vs with it.

What the day looks like when you keep winging the prompt, and what it looks like when you stop.

The prompt
Without it

Generic prompt. Claude writes something that could be about anyone, in any industry, from anywhere. Sounds like a template because it is one.

With it

The CLSkills prompt with placeholders for your context. Claude writes it like a specialist who actually knows the work. Publishable after one edit pass.

The workflow
Without it

You paste, Claude answers, you rewrite, you paste again. Ten minutes of back-and-forth per output. Three hours across a batch of five.

With it

Prompt loaded once. You feed the specifics, Claude returns the finished output. Two minutes per, twenty across five. Same tone, same structure, every time.

The result
Without it

Middle-of-the-road copy that reads AI-flavoured. Recipients notice. Response rates stay low. You end up rewriting most of it anyway.

With it

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.

The prompt

Copy this, replace the placeholders, ship.

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 context.

Codes that help

Stack these prefixes for compound gains.

Prepend one or more of these to the prompt above. Each code is documented on its own page with before and after examples.

REASONV=2REFINE

Every prompt, once.

The Cheat Sheet is every tested code, with a before and an after.

Get the Cheat Sheet, $19Read the free guide
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