First Look at Gemini’s Inline Features

In professional development, the first version of a script is rarely the end of the story. We often inherit code—sometimes from teammates, other times from our past selves—and need to understand, improve, and ensure its quality. That’s the real cycle of software maintenance.

In this lesson, we’ll take on that exact challenge. A new script, password_generator.py, has been added to the project, and it’s our job to own it. Before integrating it, we’ll need to review the logic, add features for new requirements, and ensure reliability.

This scenario will help us explore Gemini’s inline features. We’ll see how to go beyond basic code generation and work with Gemini to explain, improve, and validate code inside the editor.

Understanding existing code with “Explain This”

Before we can confidently make changes or add new features, our first responsibility is to fully understand the code we have been given. While our password generator script is simple, this principle is critical when dealing with complex, unfamiliar functions in a large codebase. Instead of manually tracing the logic, let’s ask our AI collaborator to explain clearly.

1. Open the password_generator.py file in the editor.

2. Select the entire generate_password function.

3. Click the lightbulb icon at the top of the selected code to open the smart actions menu. From this menu, find and select “Gemini: Explain This.” Alternatively, the selected code will appear as a context in the chat box. Type the prompt “Explain this” and press “Enter.”

This action will open the Gemini chat panel, which will now contain a clear, natural language explanation of the selected code. It will break down the function’s purpose and walk through the logic step-by-step. This feature is invaluable for quickly getting up to speed on any new or unfamiliar codebase, significantly reducing the time required for initial exploration.

Adding a feature with inline code completion

Now that we understand the script, it’s time to extend it. The next requirement is to support a simpler password option that uses only ...