Debugging and Refactoring with Cursor

In this lesson, we’ will explore how Cursor helps us debug and refactor existing code. We’re intentionally starting with a simple example to concentrate on learning how to use Cursor’s features effectively. The objective is to build confidence in the workflow and tools before we advance to a more complex project later.

We’ll use Cursor to:

• Identify and fix runtime errors or faulty logic.

• Detect bad practices like redundant code or inconsistent naming.

• Break down large functions into smaller, cleaner parts.

• Apply standard refactoring techniques to improve structure and maintainability.

• Locate relevant logic using both keyword and semantic search.

Debugging and refactoring are part of the natural development process, and Cursor is designed to support both. By selecting code, submitting prompts, and reviewing suggestions, we can improve code quality while staying focused on the broader task.

Starting with a buggy script

Let’s say we’re handed a simple script that is meant to calculate the average of even numbers in a list. At first glance, it looks functional, but when we try to run it, we encounter a runtime error.

Here’s the original code: