Unity 6 with the official agent plugin

# AGENTS.md: Unity 6 with the official Unity agent plugin

This project uses Unity 6+ and Unity's official agent plugin (skills that edit scripts, scenes and assets, and can run
C# in the open Editor through the Unity CLI). Those changes are powerful and not always undoable from the Editor.

## Before changing anything
- `git status` must be clean. If it is not, ask the human to commit or stash first. Commit before every larger change
  (new system, scene restructuring, import-setting changes, package changes).
- Confirm the Unity version (`ProjectSettings/ProjectVersion.txt`) is 6000.x. The plugin requires Unity 6 or later.

## How to change things
- Prefer the plugin's skills and the Editor (through the Unity CLI) for scenes, prefabs, ScriptableObjects and import
  settings. Do not hand-edit `.unity`, `.prefab` or `.asset` YAML unless the human asks; references break silently.
- Every asset has a `.meta` file with its GUID. Move and rename assets in the Editor, or move the `.meta` with the asset.
  Never delete or regenerate `.meta` files.
- Never edit `Library/`, `Temp/`, `Logs/`, `obj/` or `UserSettings/`. They are generated and git-ignored.
- Packages: change `Packages/manifest.json` only when asked, one package per commit, and note the version.
- Scripts: one public type per file, file name matches the class. Use the existing assembly definitions (`.asmdef`).

## Checking your work
- After script changes, check the Editor console for compile errors before anything else.
- Run tests when the project has them:
  `Unity -batchmode -projectPath . -runTests -testPlatform EditMode -testResults ./TestResults/editmode.xml`
  (close the Editor first, or use the Test Runner inside it). PlayMode tests use `-testPlatform PlayMode`.
- For visual changes, ask the human to look, or capture a Game view screenshot through the plugin when available.
- Summarise which scenes, prefabs and assets you changed so the human can review them in the Editor.

Use the `unity-plugin-setup` skill if the plugin is not installed.

# CLAUDE.md

@AGENTS.md

## Claude Code notes
- Skills from this loadout live in `.claude/skills/`: `unity-plugin-setup`. Use them when their description matches the task.
- Follow AGENTS.md above; where this file and AGENTS.md disagree, AGENTS.md wins.

<!-- From the Agent Loadout "Unity 6 with the official agent plugin" v1.0.0 — https://loadout.jnw-it.com/loadouts/unity-agent-plugin/ -->

# GEMINI.md

@./AGENTS.md

## Gemini CLI notes
- Skills from this loadout live in `.agents/skills/`: `unity-plugin-setup`. Use them when their description matches the task.
- Follow AGENTS.md above; where this file and AGENTS.md disagree, AGENTS.md wins.

<!-- From the Agent Loadout "Unity 6 with the official agent plugin" v1.0.0 — https://loadout.jnw-it.com/loadouts/unity-agent-plugin/ -->

---
description: Unity C# script conventions.
globs: Assets/**/*.cs
alwaysApply: false
---

- One public type per file; the file name matches the type. Namespaces follow the folder under `Assets/Scripts/`.
- Serialise private fields with `[SerializeField] private`, not public fields.
- Cache component lookups in `Awake`; no `GetComponent`, `Find` or allocations in `Update`.
- Use `TryGetComponent` instead of `GetComponent` plus a null check.
- Do not compare Unity objects with `?.` or `??`; use `== null` or implicit bool, which respect destroyed objects.
- New input code uses the Input System package, not `UnityEngine.Input`, if the project has it installed.

---
name: unity-plugin-setup
description: Install and check Unity's official agent plugin for Claude Code or Codex, and prepare the project (git, ignore file, Unity CLI). Use when the Unity skills are missing or before the first agent session in a Unity project.
---

# Set up the Unity agent plugin

1. **Project checks.** Unity 6+ (`ProjectSettings/ProjectVersion.txt`). The project is a git repository with a Unity
   `.gitignore` that excludes `Library/`, `Temp/`, `Logs/`, `obj/`, `UserSettings/`. If not, propose one and ask.
2. **Install** (the human runs these; they change the agent's own configuration):
   - Claude Code, inside a session: `/plugin marketplace add Unity-Technologies/unity-agent-plugin`, then
     `/plugin install unity@unity-agent-plugin`. From a terminal: `claude plugin marketplace add …` and
     `claude plugin install unity@unity-agent-plugin`, then `/reload-plugins`.
   - Codex: `codex plugin marketplace add Unity-Technologies/unity-agent-plugin`, then `codex plugin add unity@unity-agent-plugin`.
3. **Check.** Claude Code: typing `/unity:` lists the skills. Codex: `codex plugin list` shows `unity`.
4. **Unity CLI.** Many skills work best with the Unity CLI talking to the open Editor. When a task needs it, the plugin
   offers to install it; tell the human before accepting, because it adds a package to the project. Commit first.
5. **First task.** Start with something small and reviewable (a settings screen, an input mapping) and review the diff
   and the scene changes in the Editor before larger work.

Source: github.com/Unity-Technologies/unity-agent-plugin (README, checked 16 October 2026).