Antigravity Plugin
The Constellation plugin for Google Antigravity upgrades your AI-assisted development workflow from text search to code understanding. It provides custom slash commands, contextual skills, always-on rules, and event hooks that leverage Constellation's code intelligence platform.
Source: github.com/ShiftinBits/constellation-antigravity
Overview
| Feature | Description |
|---|---|
| 6 Commands | Custom slash commands for connectivity checks, impact analysis, architecture overview, and more |
| 2 Skills | Procedural guidance for troubleshooting and impact analysis |
| Rules | Always-on guidance steering the agent toward graph-backed code understanding |
| 2 Hooks | Context injection and transparent tool steering toward code_intel |
| MCP Server | Bundled code_intel server connection, no separate setup |
Installation
Prerequisites
- Google Antigravity installed
- A Constellation account
- Constellation CLI utility installed
- A project previously indexed in Constellation
Quick Start
-
Install the plugin:
Enter the following in your terminal:agy plugin install https://github.com/ShiftinBits/constellation-antigravity -
Configure authentication:
Enter the following in your terminal:npx @constellationdev/cli auth -
Verify the connection:
Enter the following in Antigravity:/constellation:status
Manual Install
Alternatively, clone (or copy) the plugin repository into one of Antigravity's plugin locations:
| Scope | Location |
|---|---|
| Workspace | <workspace-root>/.agents/plugins/constellation/ |
| Global | ~/.gemini/config/plugins/constellation/ |
Antigravity scans these directories automatically and loads the plugin's commands, skills, rules, hooks, and MCP server. To uninstall a manual install, remove the plugin directory.
Commands
The plugin adds several slash commands to Antigravity for quick access to Constellation's features.
Status
/constellation:status
Check API connectivity and project indexing status.
> /constellation:status
Status: Connected
Project: my-awesome-app
Files Indexed: 1,247
Symbols: 8,932
Languages: TypeScript, JavaScript
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> [file-path]
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 procedural guidance that Antigravity activates based on conversation keywords.
Constellation Troubleshooting
Diagnostic procedures for Constellation-specific errors, indexing problems, MCP server issues, and connectivity failures. Includes a quick error code reference (AUTH_ERROR, PROJECT_NOT_INDEXED, SYMBOL_NOT_FOUND, FILE_NOT_FOUND, API_UNREACHABLE).
Impact Analysis
Pre-change risk assessment guidance. Triggered by questions like "impact of changing X", "what would break if I modify X", "blast radius", "risk of renaming X", or "safe to delete X". Walks through symbol lookup, dependent enumeration, test coverage, and recommendation reporting.
Rules
The plugin ships an always-on rule (rules/constellation.md) that establishes Constellation as the agent's primary code sense: structural queries, impact analysis, and architecture questions go to code_intel; literal text search falls back to grep.
Hooks
Hooks transparently steer Antigravity toward code_intel for structural code questions. All hooks are gated on CONSTELLATION_ACCESS_KEY being set (prefix ak:) and never block execution.
| Hook | Event | Matcher | Behavior |
|---|---|---|---|
constellation-context | PreInvocation | — | Injects code_intel awareness as an ephemeral message on the first model invocation of each conversation |
constellation-tool-steering | PreToolUse | grep_search|find_by_name|run_command | Reminds Antigravity to prefer code_intel when it reaches for text search, file search, or shell commands containing grep, rg, glob, awk, or findstr |
The PreToolUse hook always returns decision ask, which defers to Antigravity's normal permission flow. It never grants (allow) or blocks (deny) tool calls; it only attaches a steering reason.