How to explain code with AI
A practical guide to getting real, useful explanations out of Retardify when you're staring at code you didn't write, don't fully understand, or haven't touched since you learned to code. Includes prompts you can copy and use right now.
Most of the time, confusing code isn't confusing because it's badly written — it's confusing because you're missing context nobody wrote down. The original author knew why they did it that way. You're reading it six months (or six years) later with none of that context, and the comments, if there are any, explain what the code does, not why.
An AI explainer is good at filling that gap fast: it reads the syntax, infers the intent, and tells you what's actually going on in language pitched at whatever level you need — from "just tell me what changed" to "explain this like I've never seen a for-loop." The rest of this guide is example prompts and settings that actually work well, organized by the situation you're probably in.
Prompts you can use
Paste your code first, then one of these — or just paste the code alone and Retardify will give you a solid default explanation without any extra instruction.
Understanding a function
“Explain this function line by line.”
“What does this function return, and under what conditions?”
Understanding a whole file
“Give me a high-level overview of what this file does, then break down each function.”
Debugging
“What edge cases does this code NOT handle?”
“Explain why this might throw an error, and what would trigger it.”
“What would happen if I removed this null check?”
Learning a new language by comparison
“I know Python but not Rust — explain this Rust code by comparing it to how I'd write the equivalent in Python.”
Swap in whatever language you actually know.
Code review, in plain terms
“Review this code and point out anything that looks like a bug, a bad practice, or a security risk, and explain why in plain English.”
Legacy or undocumented code
“This is an old script with no documentation. Explain what it does step by step, and flag anything that looks risky to change.”
Studying for an interview
“Explain this algorithm's time and space complexity, and walk through why.”
Follow-ups (in the same session)
“What does that second parameter actually do?”
“Can you explain that again assuming I'm a complete beginner?”
“Give me a real-world analogy for what this cache is doing.”
Retardifier levels for code specifically
The Retardifier slider matters more for code than almost anything else you'd paste in, because "how much do I already know" varies enormously between an experienced engineer reading unfamiliar syntax and someone who started learning to code last week.
Expert
You know the language, you just hit unfamiliar syntax or an unfamiliar library. Minimal hand-holding, fast structural read.
Technical / Clear
You code, but not in this language or framework. Good default for reviewing a teammate's PR in something you don't write daily.
Significant
You're learning to code, or the codebase is genuinely unfamiliar. Analogies, short sentences, more structure.
Maximum
Complete beginner, or teaching one. Every keyword and concept defined, nothing assumed.
Real use cases
Inheriting a legacy codebase
New job, new codebase, zero documentation. Instead of reading file by file with no context, paste the entry point or the file you're about to change and ask for a walkthrough before you touch anything.
Learning your first (or fifth) language
Tutorials teach syntax in isolation. Real code teaches you how syntax gets used. Paste real code in the language you're learning and set Retardifier to 70+ for a beginner-friendly breakdown.
Reviewing a teammate's PR in an unfamiliar framework
You can approve a PR faster if you actually understand what changed, not just that the tests passed. A quick explanation at a moderate Retardifier level often catches things a glance wouldn't.
Understanding a library before you depend on it
Before you add a dependency, paste the part of its source that matters to you and ask what it actually does under the hood — especially useful for anything handling auth, payments, or data you can't afford to misunderstand.
Tips
- For anything nontrivial — legacy code, security-sensitive logic, unfamiliar languages — use Retardify Pro (3 credits). It auto-routes to our strongest model for code and is noticeably better on ambiguous or complex input.
- Break very large files into logical sections (one function or class at a time) rather than pasting the whole thing at once — you'll get a more focused explanation.
- Export any explanation as PDF or Word if you want to keep it as informal documentation for the codebase.
- Ask follow-ups in the same session instead of starting over — the model keeps the original code in context.