How to use LLMs Ethically in a Coding Interview

July 11, 2025
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Ever stared at a tough coding problem during an interview and thought, "I could solve this in two seconds if I just asked ChatGPT"? You're not alone. 73% of developers admit they've considered using AI tools during interviews.

Let's be real: LLMs are part of a programmer's toolkit now. The question isn't if you should use them, but how to use them ethically in high-pressure situations like coding interviews.

Using LLMs ethically in coding interviews isn't just about following rules—it's about demonstrating your authentic skills while leveraging modern tools appropriately. The best candidates know exactly where to draw the line.

But here's the million-dollar question: How do you know when you've crossed from "smart preparation" into "unfair advantage" territory?

Understanding the Role of LLMs in Coding Interviews

What LLMs can legitimately help with

LLMs aren't cheating tools—they're genuinely useful assistants when used right. During interview prep, they excel at explaining complex algorithms you're struggling with. Stuck on dynamic programming? Ask an LLM to break it down step-by-step in plain English.

They're also fantastic for generating practice problems similar to ones you've been working on. Want more tree traversal challenges? Just ask.

Code review is another sweet spot—paste your solution and get feedback on edge cases, efficiency, or style issues before your interview. This helps you develop that critical eye interviewers love.

Where LLMs fall short

The brutal truth? LLMs can't replace actual coding experience. They'll happily generate solutions that look perfect but contain subtle bugs or performance issues that only surface when you actually run the code.

They also struggle with truly novel problems—the kind interviewers design specifically to test your thinking, not your memorization. And let's be real: they have no clue about your specific interview context, company culture, or the exact requirements of the role.

Most critically, they can't demonstrate YOUR problem-solving process—the very thing interviewers are evaluating.

Recognizing the ethical gray areas

The coding interview minefield has plenty of ethical gray zones. Is it okay to use an LLM to outline an approach but code it yourself? What about checking your completed solution? Does the company have explicit policies?

The trickiest part is that different companies and interviewers have wildly different expectations. Some embrace AI tools as part of modern development, while others consider any AI assistance as misrepresenting your abilities.

Remember that interviews assess not just technical skills but integrity. Using AI without disclosure might get you hired, but it could set you up for failure if the job requires skills you don't actually have.

Setting personal boundaries before the interview

Before you even open that interview link, decide exactly how you'll use AI tools. Create clear rules for yourself:

  • Will you use LLMs only for preparation but never during the actual interview?

  • If using during the interview, will you explicitly inform your interviewer?

  • Which specific aspects will you rely on your own skills for, no matter what?

Write these boundaries down somewhere. The pressure of an interview is real, and having predetermined guidelines prevents in-the-moment rationalizations.

Consider practicing a simple script for transparency: "I sometimes use AI tools like ChatGPT to help with [specific aspects]. Would you like me to avoid that during this interview, or would you prefer I explain when I'm using assistance?"

This approach shows professionalism and integrity—qualities that often matter more than solving every problem perfectly.

Transparency with Interviewers

When and how to disclose LLM usage

Honesty goes a long way in coding interviews. If you've used ChatGPT or another LLM to prepare or practice, just say so.

The best moment to bring this up? When you're discussing your solution approach. A simple "I researched this problem type using ChatGPT and learned about the sliding window technique" works perfectly. No need for a dramatic confession - just a straightforward acknowledgment.

Most interviewers appreciate transparency. Many use these tools themselves and understand their value for learning. The key is framing it as a learning aid rather than a crutch.

Bad approach: "ChatGPT wrote this entire solution for me."
Good approach: "I used ChatGPT to understand the conceptual approach, then implemented it myself."

Explaining your reasoning process

This is where you shine beyond any AI assistance. Walk through your thought process step by step:

  1. Start with how you recognized the problem type

  2. Explain the algorithms you considered and why

  3. Talk through your implementation choices

  4. Mention trade-offs you evaluated

Don't just recite memorized solutions. If an interviewer asks why you chose a particular approach, have a real answer ready. "I went with a hash map because access time is O(1)" shows you understand the why, not just the how.

Differentiating between AI assistance and your own knowledge

Draw clear lines between what you learned from AI tools and what you truly understand. Some effective phrases:

  • "The LLM helped me understand this concept, and now I can explain why it works..."

  • "I originally saw this pattern through ChatGPT, but I've since implemented it in several projects..."

  • "While ChatGPT suggested this approach, I modified it by..."

Remember that interviewers value intellectual honesty above perfect answers. They're hiring you, not your AI assistant. When you're upfront about which parts came from where, you demonstrate integrity - something no AI can fake.

Ethical Preparation Strategies

A. Using LLMs to understand concepts, not memorize solutions

LLMs can be your study buddy, not your cheat sheet. There's a world of difference between asking ChatGPT "solve this binary tree problem for me" versus "explain how binary trees work." The first approach short-circuits your learning; the second supercharges it.

When preparing for interviews, use AI to break down complex algorithms or data structures you're struggling with. Ask for multiple explanations until something clicks. The goal? Understanding the why behind solutions, not just memorizing steps.

Try this instead of copying solutions:

  • Ask for conceptual explanations in different ways

  • Request analogies that make abstract concepts concrete

  • Have the LLM quiz you on the concept afterward

B. Practicing with AI tools before the interview

Getting comfortable with AI tools before your interview isn't cheating—it's smart preparation. Think of it like practicing with the calculator you'll use during a math test.

Set up mock interviews where you deliberately practice using LLMs as reference tools. Time yourself. See how long it takes to get useful information versus solving problems on your own. This helps you develop judgment about when AI assistance is actually helpful versus when it's a time sink.

Create scenarios where you:

  • Deliberately get stuck, then ask targeted questions

  • Practice explaining your thought process while referencing AI insights

  • Learn to extract principles rather than solutions

C. Creating a personal ethical framework

Nobody's going to hand you a rulebook for ethical LLM use in coding interviews. You need to build your own.

Start by asking yourself some tough questions:

  • What would I be comfortable telling the interviewer I used AI for?

  • Where's the line between assistance and dependence?

  • How can I ensure I'm being evaluated on my skills, not OpenAI's?

Your framework might look different from someone else's, and that's fine. What matters is consistency and honesty with yourself. Write down your boundaries and review them before interviews.

D. Learning from AI-generated explanations rather than code

The magic isn't in getting AI to write your code—it's in getting AI to help you think better.

When reviewing solutions to practice problems, don't just ask for code. Request:

  • Multiple solution approaches with trade-offs explained

  • Step-by-step reasoning behind each line

  • Common pitfalls and edge cases to watch for

Take that generated explanation and try to implement the solution yourself without looking at the AI's code. This forces you to engage with the concepts rather than copy-pasting.

The strongest candidates don't use AI to avoid thinking—they use it to think more deeply.

During the Interview: Ethical Usage Guidelines

A. Acceptable scenarios for LLM consultation

You're stuck on a syntax issue that's eating up your time? That's when an LLM can be your friend. It's perfectly fine to use AI assistance for:

  • Looking up standard library functions you can't quite remember

  • Checking syntax for a particular language feature

  • Debugging simple errors when you know what you want but typed something wrong

  • Getting a quick refresher on an algorithm you already understand

Think of LLMs as your coding dictionary—not the author of your work. The key is using them to enhance your existing knowledge, not replace your problem-solving.

B. When to avoid AI assistance entirely

Hands off the AI when:

  • You're asked to solve a core algorithmic problem

  • The interviewer explicitly says "no external resources"

  • You're being evaluated on specific problem-solving approaches

  • The question is designed to test your fundamental understanding

If you're being asked how to implement a binary search tree from scratch, the interviewer wants to see YOUR implementation, not ChatGPT's perfect textbook version.

C. Balancing efficiency with authenticity

The sweet spot exists! Use LLMs to:

  • Get unstuck when you've already demonstrated your approach

  • Verify your solution after you've completed it

  • Enhance a working solution you've already created

Always make it clear what's yours and what's assisted. Say something like: "I've implemented the core logic here, but I'd like to check if there's a more efficient way to handle this edge case."

D. Managing time constraints ethically

Coding interviews are pressure cookers. Here's how to ethically handle the clock:

  • Start with your own approach first, give it a solid attempt

  • Set a mental timer—if you're stuck for more than 5-7 minutes on something trivial, consider AI help

  • Use LLMs strategically for boilerplate code to focus on the algorithmic meat

  • If using AI to save time, spend the saved minutes explaining your thought process

E. Handling unexpected problems

When things go sideways:

  • If you hit an unexpected roadblock, try solving it yourself first

  • When using AI for help, narrate what you're doing: "I'm running into an issue with this regex pattern, let me verify the syntax"

  • If the AI gives you a solution you don't understand, don't use it

  • Have a backup plan for when AI tools aren't available or give unhelpful responses

Remember, the interviewer is hiring you, not your AI assistant. Show them you can think critically even when things don't go as planned.

Demonstrating Your Unique Value

A. Adding human creativity beyond what LLMs offer

LLMs are impressive code generators, but they can't replicate your unique creative approach. When an interviewer asks you to solve a problem, show how you can think outside the algorithmic box.

Try this: after implementing the standard solution, add your own creative twist. Maybe it's a clever optimization based on your experience with similar systems, or perhaps it's an elegant way to handle edge cases that wouldn't be in training data.

For example, if you're building a search function, don't just implement binary search—explain how you'd adapt it for your company's specific user behavior patterns or data structures.

Your creativity is your superpower. LLMs output what they've seen before. You can innovate.

B. Showcasing problem-solving thought processes

The magic happens when you think out loud. While LLMs spit out complete solutions, your interviewer wants to see your mental gears turning.

Walk them through your reasoning:

  • "I'm considering approach X because..."

  • "This reminds me of problem Y I've solved before..."

  • "Let me sketch this out to visualize the data flow..."

Break down complex problems into manageable chunks. Show how you identify bottlenecks and constraints before coding. This demonstrates a skill LLMs fundamentally lack: the ability to metacognitively analyze their own problem-solving approach.

C. Communicating architectural decisions that LLMs struggle with

LLMs can write code snippets, but they often miss the bigger picture. This is your chance to shine.

When discussing system design:

  • Explain tradeoffs between different approaches

  • Consider real-world constraints like deployment environments

  • Address scalability concerns proactively

  • Connect technical choices to business requirements

Say something like: "I'd choose microservices here because our team structure has five separate groups that would need to coordinate on a monolith, and the deployment complexity is worth the development autonomy."

These contextual, nuanced architectural decisions show you're not just regurgitating patterns but applying judgment based on experience.

D. Highlighting your debugging and testing approaches

Anyone can write code. Exceptional engineers know how to verify and fix it. Show interviewers your systematic approach to quality.

Share your testing strategy:

  • How you identify critical test cases

  • Your approach to edge cases

  • Tools and techniques you use to catch bugs early

When discussing debugging, demonstrate methodical thinking: "When I see this error, I first check X, then Y, and finally Z before making changes."

Talk about how you've debugged tricky production issues in the past. These war stories prove your resilience and problem-solving abilities in ways an LLM simply cannot match.

Post-Interview Reflection

Evaluating your reliance on AI tools

The coding interview is over, but your learning journey isn't. Take a minute to honestly assess how much you leaned on LLMs during your interview. Did you use them as a crutch or as a supplement to your knowledge?

Ask yourself these tough questions:

  • Could I have solved the problem without AI assistance?

  • How much of the solution was my original thinking versus generated code?

  • Did I understand every line of code the LLM suggested?

If you found yourself blindly implementing AI suggestions, that's a red flag. The goal isn't to become dependent on these tools but to grow beyond needing them for basic problems.

Identifying knowledge gaps to address

The interview revealed something valuable: your weak spots. Those moments when you frantically asked ChatGPT for help? Those are gold - they point directly to what you need to study.

Make a list:

  1. Concepts you struggled to explain

  2. Algorithms you couldn't implement without help

  3. Language features you had to look up

These aren't failures - they're your personalized study guide. Each gap represents an opportunity to strengthen your foundation.

Setting development goals for reduced dependency

Now comes the action plan. Don't aim to eliminate AI tools completely - that's unrealistic. Instead, set concrete goals to become more self-sufficient:

  1. Master one algorithm or data structure per week without AI help

  2. Implement solutions to practice problems before checking against AI suggestions

  3. Set a "look-up budget" - limit yourself to 3 AI queries per problem

Track your progress. Notice how questions that once required AI assistance become manageable on your own. That's real growth - and no AI can take credit for it.

Conclusion

The ethical use of Large Language Models in coding interviews is not just about following rules—it's about maintaining your integrity while showcasing your genuine skills. By being transparent with interviewers, preparing ethically with LLMs as learning tools rather than shortcuts, and using them appropriately during interviews only when permitted, you position yourself as both technically skilled and professionally honest. Remember that LLMs should supplement your abilities, not replace them, and always prioritize demonstrating your unique problem-solving approach.

As you move forward in your tech career, establish personal boundaries for AI tool usage that align with industry expectations and your professional values. Whether you're a job seeker or interviewer, fostering open discussions about AI-assisted coding creates a healthier tech ecosystem built on trust and authentic skill evaluation. The most successful candidates aren't those who rely most heavily on AI, but those who thoughtfully integrate these tools while maintaining their distinctive technical voice and ethical standards.

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