Exploring Google’s New Gemini CLI: The Ultimate Open-Source Dev Tool

This year, the most revolutionary developer tools I’ve used didn’t come with a splashy launch or billion-dollar hype.

It came as a simple CLI:
Gemini CLI, a terminal-based AI agent built on top of Google’s Gemini 2.5 Pro model.

At first glance, it looks like a lightweight alternative to Claude Code. But after just 10 minutes of use, it became clear: this isn’t just a convenient utility. It’s a powerful local AI development assistant that can analyze, automate, and accelerate almost every part of your software workflow.

And best of all?

• It’s fully open-source under the Apache 2.0 license
• It gives you up to 1,000 free requests per day
• It integrates with your local filesystem, IDE, and the web
• And it runs entirely in your terminal, no browser needed

In this guide, I’ll show you what Gemini CLI is, how it works, how to install it, and what it can do, step by step, with real examples and screenshots.

What Exactly Is Gemini CLI?

Gemini CLI is a local command-line tool that connects you directly to the Gemini 2.5 Pro model, Google’s flagship AI, via natural language prompts.

Once installed, it gives you a prompt inside your terminal where you can do things like:

• Ask it to generate or edit code
• Summarize Git history
• Parse and modify local files
• Search the web in real-time
• Automate scripts and workflows
• Connect to external tools and APIs

It works across most major OS environments (Linux, macOS, Windows WSL) and doesn’t require a hosted cloud IDE or any proprietary environment.

Here’s why this is a big deal:

Gemini CLI brings the power of large-context, local AI interaction to the command line, where most serious developers spend their time.

Installation: Quick Setup with Node.js

Before installing Gemini CLI, you’ll need:

• Node.js 18+
• A terminal environment (Command Prompt, Terminal, PowerShell, etc.)

To check your Node version:

node -v

If it’s below version 18, update it from the Node.js website.

Once ready, install Gemini CLI with:

npx https://github.com/google-gemini/gemini-cli

Or install it with:

npm install \-g @google/gemini-cli

Then open it using:

gemini

This uses NPX to fetch the CLI package and initialize the prompt.

You’ll be guided through:

1. Theme Selection Choose a light or dark terminal theme.
2. Authentication You can authenticate via:
3. Google Account (recommended, no setup needed)
4. Gemini API Key (if you want higher request limits)

Once authenticated, you’ll be dropped into the Gemini CLI interface. It looks like a REPL (read-eval-print loop), waiting for your command.

What You Can Do With Gemini CLI (Real Use Cases)

1. Summarize Project Changes in Seconds

Want a high-level overview of what changed in your repo yesterday?

Just clone the repo, navigate into the directory, and run:

gemini

Then ask:

Give me a summary of all the changes from yesterday.

Gemini will scan your codebase, Git logs, and commit messages, and provide a structured summary, without needing to write a custom script or manually grep logs.

Use Case: Perfect for team leads doing daily stand-ups or changelog generation.

2. Build Full Applications From a Prompt

I asked:

Create a modern web app that acts as an image editor with contrast, brightness, and hue controls.

In less than a minute, Gemini generated:

• An HTML front-end
• CSS styles for layout and controls
• JavaScript to manipulate images
• A functioning UI with upload, filter, and draw tools

Insight: This isn’t a static code dump. It builds **runnable, structured projects* and can iterate on them based on follow-up prompts.*

3. Live Google Search From Terminal

Need real-time information?

Gemini CLI has a Google Search integration. Simply type:

Search: weather in New York City today

Gemini queries Google Search behind the scenes and delivers summarized results right in your terminal.

This also works for:

• Tech documentation
• Latest GitHub repo status
• StackOverflow answers

Note: You can whitelist or restrict network access depending on your security context.

4. Automate File and Script Operations

Gemini CLI supports:

• read_file and read_folder functions
• File editing
• Script generation
• Bash workflow automation

Example prompt:

Write a shell script that backs up all .en files in this directory and compresses them into a timestamped ZIP.

Output:

A working .sh script, timestamped, ready to run. It even explains each step.

5. Extend With MCP Servers and Tools

Gemini CLI connects to MCP servers for multimedia capabilities like image and video generation.

You can generate 30-second videos using Google Cloud’s GenMedia API or send prompts to external models via prebuilt endpoints.

Also available:

• Bug report submission
• Theme changes
• Chat context compression
• External tool plugins
• Memory stat tracking

Prompt example:

Generate a 30-second video of a cat on a plane.

Advanced: Use Inside IDEs with Code Assist

Gemini CLI is also integrated with Gemini Code Assist, a Google-built IDE plugin.

Once installed in your editor (VS Code, JetBrains, etc.), you can use Gemini directly inside your coding environment and:

• Run terminal prompts
• Auto-generate code from file context
• Debug existing functions
• Trigger CLI requests without switching tabs

This makes Gemini CLI a fully embedded development AI, not just a terminal utility.

Final Thoughts:

Gemini CLI is more than a cool open-source release; it’s a vision of the future:

• Local-first AI
• Full project comprehension
• Live web capabilities
• Dev-native interaction
• Open extensibility

It doesn’t ask you to learn new platforms. It meets you in the terminal. And it delivers powerful results, fast.

Whether you’re building solo, leading a dev team, or just exploring AI for the first time, Gemini CLI gives you a real, free, and flexible entry point into the next-gen developer workflow.

Thank you for being a part of the community