Claude Code Tutorial: How to Generate, Debug and Document Code with AI

What is Claude Code?

Claude Code is an AI-powered coding assistant developed by Anthropic. It helps developers write, understand, and improve code using natural language prompts.

Unlike traditional tools that focus solely on generating output, Claude is designed for collaboration. It can explain code, suggest improvements, and even help debug code while maintaining clarity and context.

It’s designed using Anthropic’s Constitutional AI framework, which guides the model to produce helpful, harmless, and honest responses, making it particularly well-suited for real-world development tasks.

Let us look at the key benefits of using Claude Code in the development workflow.

Benefits of Claude Code

Claude Code enhances development workflows by combining AI-powered natural language interaction with coding tasks. It simplifies repetitive processes, improves team collaboration, and boosts productivity. Here are five key benefits:

• Effortless Code Navigation: Navigate the codebase easily using plain language commands. Claude simplifies tasks like file management and variable renaming, streamlining everyday coding.

• Instant Code Explanations: Claude provides clear explanations and summaries of complex code, helping teams quickly grasp project architecture, especially when dealing with legacy code or unfamiliar modules.

• Task Automation: Automate repetitive tasks such as running tests, committing changes, or fixing linting issues, freeing up time for more critical development work.

• Efficient Bug Fixing and Optimization: Claude can help identify bugs and suggest improvements, like optimizing slow functions or refactoring messy code.

Now that the benefits of Claude Code are highlighted, let’s set it up on our local device and start using it.

Setting up Claude Code on a local device

Before diving into the installation of Claude Code, it’s important to understand the system requirements. Claude Code can run on macOS, Ubuntu, Debian, and Windows devices via Windows Subsystem for Linux (WSL). Let’s go through the installation process step by step for the operating systems.

System requirements for Claude Code

Claude Code supports the following operating systems:

• macOS: Version 10.15 and above.
• Ubuntu: Version 20.04 and above.
• Debian: Version 10 and above.
• Windows: Available via Windows Subsystem for Linux (WSL).

For Windows users, WSL must be installed first. WSL allows us to run a Linux environment directly on Windows, making it easier to manage and work with tools like Claude Code.

Install Windows Subsystem for Linux (WSL) on Windows

To install WSL, follow the instructions:

• Open the command prompt
• Run the following command to install WSL:

wsl --install

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To complete the installation process, follow the on-screen prompts.

Install Claude Code

Once WSL is set up (for Windows users) or the terminal is ready (for macOS/Ubuntu users), you can proceed with installing Claude Code.

• Open WSL by searching for “Ubuntu” or your chosen Linux distribution in the Start menu. For macOS and Ubuntu users, open the terminal.
• In the terminal (or WSL), run the following command to install Claude Code globally via npm:

npm install -g @anthropic-ai/claude-code 

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This command will install Claude Code and make it available globally on the system.

Note: Ensure that Node.js is installed on your system before installing Claude Code. If you don’t have Node.js installed, download it from the Node.js official download page. Claude Code relies on Node.js, a JavaScript runtime environment, to execute locally.

Note: If Claude Code doesn’t install correctly on WSL due to OS or platform detection issues, check the “Troubleshooting WSL installation” section in the official Claude Code documentation.

You can select your preferred text color among the given themes to get started.

Generate API key from Anthropic console

You’ll need an API key to interact with Claude Code. Follow these steps to generate your key:

• Navigate to the Anthropic Console by following the instructions on the terminal.

• Log in or create an account if you haven’t already done so.
• Go to the API section and generate a new API key.

The API key in the image is kept hidden due to security reasons

Configure Claude Code with the API key

Once you have your API key, you need to configure Claude Code. Here’s how to do it:

• Paste the API key in the WSL or terminal when prompted.
• Follow the on-screen instructions to authenticate your setup.

Claude Code has finally been installed on our device, and we can begin integrating it into the development workflow!

Now, let us understand how to effectively use Claude Code to boost efficiency in real-world coding scenarios.

Generating code using Claude code

Claude Code allows developers to generate and modify code using plain English prompts. Instead of writing code from scratch, describe the task, and Claude will generate clean and readable code directly in your desired file.

Navigate to the desired location

Before creating a new file, moving into the correct project directory is essential. In Claude Code, use the cd command just as you would in a terminal. For example:

cd /Users/Desktop/Codecademy/Claude-Code 

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Note: In WSL, Windows drives are mounted under the /mnt directory. So, to access your C: drive, you would use:

cd /mnt/c/Users/Desktop/Codecademy/Claude-Code

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Open or create the file

Once inside the desired folder, ask Claude to open or create the Python file:

Open palindrome.py 

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Claude will either open the file if it already exists or create a new one within the current folder. The file becomes active for any following code prompts.

Use the code . command in this terminal to open this directory in Visual Studio Code.

Prompt Claude to generate code

Now you’re ready to generate the code. Instead of using rigid syntax, describe the task using natural language. For example:

Write a Python function called is_palindrome that checks if a word is a palindrome. It should ignore case and spaces. 

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Claude responds by writing the function directly into the palindrome.py file. Here is a sample output:

def is_palindrome(word):  
  cleaned_word = ''.join(word.lower().split())  
  return cleaned_word == cleaned_word[::-1] 

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If the function needs changes, such as ignoring punctuation or handling full sentences, request an update. For example:

Update the is_palindrome function to ignore punctuation as well. 

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Claude will refine the code, and this could be a possible output:

def is_palindrome(word):
  cleaned_word = word.lower()  
  cleaned_word = ''.join(char for char in cleaned_word if char.isalnum())  
  return cleaned_word == cleaned_word[::-1] 

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It updates the file directly, so there is no need to retype or start over. As we can see, Claude Code helps developers move from idea to implementation with just a prompt.

Now that we have the code, let us try to refactor it.

Refactoring the code to improve readability

Claude Code helps improve existing code by suggesting optimizations, restructuring logic, and enhancing readability. The current is_palindrome function works, but could be cleaner or more efficient. Frame a natural language prompt to request a refactor:

Refactor the is_palindrome function to make it more readable and efficient. 

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It will return an improved version, often with enhancements like more explicit variable naming, better use of Python built-ins, or modular design. An example output can be:

def is_palindrome(text):  
  # Clean the text: convert to lowercase and keep only alphanumeric characters 
  cleaned_text = ''.join(char.lower() for char in text if char.isalnum()) 
 
  # Check if the cleaned text reads the same forward and backward 
  return cleaned_text == cleaned_text[::-1] 

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Understand the changes

One of Claude’s unique strengths is its ability to explain the reasoning behind its changes. Ask:

Explain what improvements were made and why. 

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Claude might respond:

I made several improvements to the is_palindrome function: 

1. Renamed parameter from word to text - More accurate since it handles any string, not just single words 
2. Combined cleaning operations - The new implementation does lowercase conversion inside the comprehension, reducing the code to a single operation instead of two separate steps 
3. Added comprehensive docstring - Clearly documents purpose, parameters, return values, and behavior 
4. Added descriptive comments - Explains each step of the algorithm for better readability 
5. Used more descriptive variable naming - cleaned_text better represents what the variable contains

These changes make the code more maintainable, slightly more efficient (by combining operations), and easier to understand for other developers. 

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These explanations help developers understand what changed and why, turning every refactor into a mini learning moment.

But what if the code is broken after some changes? Let us find out if Claude Code can help find and fix the error.

Debugging the code

Debugging is often the most time-consuming part of development, but with Claude Code acting like a second pair of eyes, identifying and fixing syntax mistakes or logical flaws becomes faster and more insightful. Let us introduce a small error in the is_palindrome function:

Introduce a bug

def is_palindrome(text):  
  # Clean the text: convert to lowercase and keep only alphanumeric characters  
  cleaned_text = ''.join(char.lower for char in text if char.isalnum) 

  # Check if the cleaned text reads the same forward and backward  
  return cleaned_text == cleaned_text[:-1] 

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This version contains a common mistake: isalnum and lower are used without parentheses, and one : is also removed from indexing, so the condition doesn’t work as expected.

Ask Claude to fix it

Ask Claude Code to debug with this prompt:

This function isn’t working correctly. Can you debug it? 

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It will respond as follows:

Claude Code used a set of diff tools to showcase the differences between the correct and our buggy code.

Understanding the fix

Claude Code might also provide some feedback for us to understand what bug was fixed, and it can be as follows:

I fixed two bugs: 

1. Missing parentheses for function calls: 
  - Changed char.lower to char.lower() (missing parentheses) 
  - Changed char.isalnum to char.isalnum() (missing parentheses) 

2. Incorrect slice notation: 
  - Changed cleaned_text[:-1] (which excludes the last character) 
  - To cleaned_text[::-1] (which reverses the string)  
The function should now work correctly. 

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To understand the error better, we can follow up with this prompt:

Explain the bug and how your fix solves it. 

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Once the code is working perfectly, it’s time to make it understandable for others, and that’s where documentation comes in.

Documenting the code

Well-documented code is just as valuable as clean code. Claude Code simplifies this often-overlooked step by generating professional, human-readable documentation directly from your codebase. Let us prompt for docstrings to begin with:

Add a docstring to this function with parameters and an explanation of the return value. 

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A possible output could be:

def is_palindrome(text):  
  """ Checks if a string is a palindrome. 
  A palindrome reads the same backward as forward when ignoring: 
    - Case (upper/lowercase) 
    - Spaces 
    - Punctuation and special characters 

  Parameters: 
    text (str): The string to check for the palindrome property 
     
  Returns: 
    bool: True if the string is a palindrome, False otherwise 
     
  Examples: 
    >>> is_palindrome("racecar") 
    True 
    >>> is_palindrome("A man, a plan, a canal: Panama") 
    True 
    >>> is_palindrome("hello") 
    False 
  """ 

  # Clean the text: convert to lowercase and keep only alphanumeric characters 
  cleaned_text = ''.join(char.lower() for char in text if char.isalnum()) 
  
  # Check if the cleaned text reads the same forward and backward 
  return cleaned_text == cleaned_text[::-1] 

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If there is a need for project-wide documentation for teammates or open-source contributors, ask:

Generate a markdown summary of this function. 

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It might respond something like this:

### Function: is_palindrome(text) 

Description:
- Determines whether a given string is a palindrome by removing non-alphanumeric characters and comparing the cleaned version to its reverse. 

Returns: 
- (bool): True if the input is a palindrome, otherwise False. 

Usage:
- is_palindrome("racecar")  # Returns: True 
- is_palindrome("A man, a plan, a canal: Panama")  # Returns: True 
- is_palindrome("hello")  # Returns: False 

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Now we have a clean and well-documented code, but what if it needs to be shared with teams using a different programming language?

Language translation and multi-language support

Claude Code handles the ability to translate code between languages with ease. It retains the core logic while adapting the syntax and structure to fit the conventions of the target language. Let us check this with a practical example:

Translate this Python function into JavaScript and save it as palindrome.js 

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It will respond by creating another file named palindrome.js and populating it with the desired code. Here is a sample output:

We can also request translation into other languages, like:

Translate this function into Java and save it as Palindrome.java 

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Or

Translate this function into Go and explain how string manipulation differs. 

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With Claude Code, developers can bridge language barriers effortlessly, enabling multi-platform support, team collaboration, and smoother code reuse across projects.

Best practices and limitations of Claude Code

Claude Code accelerates development and simplifies many tasks, but it works best when guided thoughtfully. Here are some of the best practices to follow:

• Be Specific with Prompts: Ambiguous instructions can lead to unexpected results. Clear, structured prompts like “Refactor this function to improve readability and add inline comments” work better than vague ones like “Make this better.”

• Break Down Complex Tasks: Instead of asking Claude to rewrite an entire project, focus on individual modules or files. This improves accuracy and speeds up response time.

• Always Review the Output: Claude Code enhances productivity, but its suggestions should still be reviewed and tested. It’s a tool for acceleration, not a replacement for quality control.

• Use Claude as a Pair Programmer: Treat it like a collaborative partner—ask it to explain changes, evaluate alternatives, or debug with you. This will help you improve your own understanding while getting the job done.

While it is a very efficient tool for the developers, it also has some limitations as listed here:

• Doesn’t Fully Understand Context Across Files: Claude Code can miss cross-file dependencies or misinterpret module-level logic in large projects.

• Not a Substitute for Domain Knowledge: Claude follows patterns and language rules but doesn’t “understand” project-specific business logic unless explicitly guided.

• Potential for Overconfidence: Claude might confidently suggest code that seems correct but fails edge cases or introduces subtle bugs. Testing is essential.

Used with care and clear prompts, Claude Code becomes a powerful asset—just be mindful of its limits.

Conclusion

In this article, we explored how Claude Code streamlines key development tasks—from generating and refactoring code to debugging, documenting, and translating across languages. Throughout, one theme remains central: the quality of your prompt directly shapes the quality of Claude’s output. Mastering how you communicate with AI is as important as knowing what to build.

To sharpen your prompt-writing skills and unlock even more from tools like Claude, explore the Learn Prompt Engineering course on Codecademy.

Frequently asked questions

1. Is Claude better than GPT for coding?

Claude and GPT offer strong coding capabilities, but Claude Code is designed to focus on collaborative workflows, natural language understanding, and context-aware assistance. It maintains code clarity, explains logic, and performs tasks like refactoring and documentation. GPT, especially in tools like GitHub Copilot, may feel more autocomplete-oriented, while Claude offers more conversational depth and reasoning.

2. How much does Claude Code cost?

Claude Code itself is free to install via Node.js. However, using it requires API access from Anthropic, which may come with usage-based pricing depending on the plan. You can check the latest pricing details on Anthropic’s official pricing page.

3. Which AI is Claude?

Claude is a generative AI model developed by Anthropic. It is designed to be helpful, harmless, and honest. It’s part of a family of advanced language models used for various tasks, from coding to writing and research. Claude Code is a developer-focused extension that uses this generative AI to offer intelligent, prompt-based coding support.