Gemini CLI Extension

The Constellation extension for Gemini CLI supercharges your AI-assisted development workflow with deep codebase understanding. It provides specialized skills, custom slash commands, and session hooks that leverage Constellation's code intelligence platform.

Source: github.com/ShiftinBits/constellation-gemini

Overview

Feature	Description
3 Sub-agents	Autonomous specialists for exploration, impact analysis, and dependency health
1 Skill	Procedural guidance for troubleshooting and complex workflows
6 Commands	Custom slash commands for connectivity checks, architecture overview, and more
3 Hooks	Intelligent context injection and preservation throughout the session

Installation

Prerequisites

• Gemini CLI installed
• A Constellation account
• Constellation CLI utility installed
• A project previously indexed in Constellation

Quick Start

1. Install the extension:

   _{Enter the following in your terminal:}

   gemini extensions install https://github.com/ShiftinBits/constellation-gemini

2. Configure authentication:

   _{Enter the following in your terminal:}

   constellation auth

3. Verify the connection:

   _{Enter the following in Gemini CLI:}

   /constellation:status

Uninstall

_{Enter the following in your terminal:}

gemini extensions uninstall constellation

Commands

The extension adds several slash commands to Gemini CLI for quick access to Constellation's features.

Status

/constellation:status

Check API connectivity and authentication status.

> /constellation:status

Status: Connected
- Authentication valid, project access confirmed
- Note: Use /constellation:diagnose to check indexing status

Diagnose

/constellation:diagnose

Perform a full health check of the Constellation connection, authentication, and project indexing.

Architecture

/constellation:architecture

Get a high-level overview of the codebase architecture, including language distribution and key modules.

Dependencies

/constellation:deps <file-path> [--reverse]

Analyze dependencies for a specific file. Use the --reverse flag to see what depends on the file.

Impact Analysis

/constellation:impact <symbol-name>

Analyze the impact of changing a specific symbol to understand the potential "blast radius" of a change.

Unused Code

/constellation:unused

Find dead code that is exported but never imported or used anywhere in the codebase.

Skills

Skills are specialized agent instructions that Gemini CLI activates based on conversation context.

Source Scout

Proactively use Constellation for code search, symbol discovery, and architectural understanding. Triggered by questions like "Where is X implemented?" or "How does payment processing work?".

Impact Investigator

Assess the risk and scope of proposed code changes. Triggered when you discuss refactoring, renaming, or deleting code.

Dependency Detective

Identify and resolve dependency issues, including circular dependencies and tight coupling. Triggered by tasks like "Check imports" or "Analyze module relationships".

Constellation Troubleshooting

Assistance with fixing Constellation-specific errors, indexing problems, or connectivity issues.

Hooks

The extension includes hooks that automatically inject Constellation context into your session:

• SessionStart: Ensures the model knows Constellation is the primary tool for code understanding.
• BeforeTool: Reminds the model to prefer code_intel over generic text search for structural queries.
• PreCompress: Preserves Constellation's architectural insights during context compaction.