How to Use AI for Coding

Coding model picks have stabilised:

• Claude Sonnet 4 — best all-rounder. Multi-file refactors, architectural questions, careful work.
• ChatGPT 4o — fastest for snippets and quick "how do I X" questions.
• ChatGPT 4.1 — deeper reasoning. For hard algorithmic problems.
• DeepSeek R1 — reasoning model that punches above its weight on competitive programming.

See our full comparison of ChatGPT vs Claude for coding.

The single most useful thing you can give the AI: the exact stack trace. Don't paraphrase. Don't summarise. Copy-paste the whole thing.

Why: error strings are unique fingerprints. AI models have seen them in training data and can often jump straight to the cause. "My code is throwing an IndexError" gets a generic answer; the actual stack trace gets the real fix.

For non-trivial bugs:

"I'm hitting this error:
[paste full stack trace]

Code that produced it:
[paste relevant code]

Tell me:
1. The most likely root cause (with reasoning)
2. The fix
3. Two other things that could cause this same error if I'm wrong about #1"

The third bullet forces the AI to consider alternatives — way more useful than a confident wrong answer.

AI-generated code looks right. It runs. It's well-formatted. None of that means it's correct.

Common AI bugs:

• Imports of functions that don't exist ("hallucinated" APIs).
• Off-by-one errors in loops and slicing.
• Race conditions in async code.
• Missing edge cases (empty inputs, None, large inputs).
• Subtly wrong return types.

Review every line. Run it. Test edge cases.

Most developers underuse AI for review. Paste your code (or someone else's) with this prompt:

"Review the code below. Focus on: bugs / logic errors, security issues, readability, performance problems that actually matter. Skip nitpicks. Be direct — assume I'm a senior engineer."

The "skip nitpicks" line is critical. Otherwise the AI flags every imperfect variable name.

For one-off translation tasks (SQL ↔ ORM, regex generation, format conversion) save the prompt as a template. AskAI.free's prompt library includes coding templates for most of these patterns.