Vibe Coding Beyond the Editor: Mastering Google Antigravity CLI and Agent Skills

Imagine a development experience where you don’t just have an AI sidebar in your IDE, but a fully contextual autonomous coding engine running natively inside your terminal.

That is exactly the paradigm shift we are living through. Terminal-based AI coding engines — specifically Google Antigravity — have completely flipped the script on “vibe coding” (Wheeler, 2026). Instead of copy-pasting snippets back and forth, these agents interact directly with your file system, shell environment, and external APIs using custom-built extensions called Skills (Chen, 2026).

But as these tools grow more powerful, they also become more unpredictable. If you’re ready to let an agent loose on your codebase, you need to understand how to control its logic, write customs skills, and — crucially — prevent it from wiping out your filesystem.

Let’s dive into how Google Antigravity works under the hood and how to build a production-safe environment for it.

🛠️ The Architecture: Understanding “Skills”
In the terminal-agent ecosystem, a “Skill” is essentially a procedural block of logic that an agent dynamically discovers, loads, and executes based on your natural language input (Chen, 2026).

[User Prompt]
│
▼
┌────────────────────────┐
│ Google Antigravity │ ◄─── Reads CLAUDE.md / Project Context
└────────────────────────┘
│
├─► [Discovers local / global skills]
├─► [Evaluates safety boundaries]
└─► [Executes Terminal / API Action]

When you prompt Antigravity to “Audit this repository for deprecated APIs and patch them,” it doesn’t just guess. It scans your context files, maps the system surface, and runs specialized multi-agent subroutines to execute the task safely (de Macedo, 2026).

🚀 Step-by-Step: Setting Up Your First Custom Skill

One of the best features of Antigravity is its extensibility. Let’s walk through creating a custom file-safety skill using a standard sequence. This ensures the agent backs up files before attempting complex, multi-file refactors.

1.Initialize the Skill Directory:Prerequisite.

Create a local configuration folder in your repository root to house your custom scripts. Antigravity looks for a .antigravity/skills/ directory by default.

Bash

mkdir -p .antigravity/skills

2.Write the Script Logic:Python / Node.js.

Create a script named backup_agent.py. This script will generate a compressed, timestamped manifest of your target directory before any destructive edit occurs.

Python

import tarfile
import os
from datetime import datetime
def backup_project():
timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
backup_name = f"pre_refactor_{timestamp}.tar.gz"
with tarfile.open(backup_name, "w:gz") as tar:
tar.add(".", filter=lambda x: None if ".git" in x.name or "node_modules" in x.name else x)
print(f"✓ Defensive backup created: {backup_name}")
if __name__ == "__main__":
backup_project()

3.Register the Skill Manifest:JSON Configuration.

Tell Antigravity how and when to use this skill by creating a metadata manifest file (backup.json). This registers the schema so the model understands its purpose.

JSON

{
"name": "defensive_backup",
"description": "Automatically backs up code files before attempting large multi-file updates.",
"runtime": "python3",
"entrypoint": "backup_agent.py"
}

4.Run and Verify:Execution.

Boot up the Antigravity CLI interface and test the execution hook explicitly:

Bash

antigravity run "Execute defensive_backup on current directory"

⚠️ The Elephant in the Room: The “Turbo Mode” Danger
We can’t talk about terminal agents without addressing security. Because tools like Antigravity have direct execution context on your operating system, giving them unchecked autonomy can be catastrophic.

A Cautionary Tale: In 2025, an auto-approve “Turbo Mode” bug in Google Antigravity famously resulted in the accidental erasure of a user’s entire secondary storage drive due to an unconstrained agent loophole (Li et al., 2026).

To prevent your agent from hallucinating a destructive rm -rf command, you should implement strict containment structures.

The Defensive Developer Checklist:

• Disable Global Auto-Approve: Never pass --yes or --turbo flags on critical machines.
• Implement Sandboxing: Always run your agent inside a Docker container or an isolated dev container.
• Use Explicit Boundaries: Use newer lattice-refinement patterns or authorization layers like ConLeash to lock down filesystem access to specified project boundaries (Li et al., 2026).

🏁 Summary Matrix: How Antigravity Measures Up

If you’re trying to figure out which terminal agent fits your team’s current stack, here is how the dominant players in 2026 stack up against each other:

Terminal-driven development isn’t just about speed — it’s about contextual intelligence. By configuring custom skills correctly and enforcing rigid execution boundaries, you transform the terminal from a passive command line into an active engineering partner.