Install the Unity plugin for Claude Code

This guide installs Unity's official Claude Code plugin through the documented marketplace route inside a Unity 6 project. Before relying on it in production, review the full [documentation](https://docs.unity.com/en-us/ai/unity-plugin/claude-code) and the [repository](https://github.com/Unity-Technologies/unity-agent-plugin).

Check the prerequisites

The plugin requires Unity 6 or newer and a current version of Claude Code (check with claude --version), or Codex as an alternative. Open Claude Code at the root of the affected Unity project, not in a parent folder.

Add the marketplace and install the plugin

Enter these slash commands in Claude Code:

/plugin marketplace add Unity-Technologies/unity-agent-plugin
/plugin install unity@unity-agent-plugin

For Codex, the repository documents the equivalent commands codex plugin marketplace add Unity-Technologies/unity-agent-plugin and codex plugin add unity@unity-agent-plugin. If you prefer a graphical flow, the Claude desktop app lets you add the repository URL as a marketplace under Plugins → Browse and install the plugin from there.

Verify the skills and choose a scope

Type /unity: in Claude Code to list the loaded Unity skills, and /plugin to confirm the installation. For team-wide consistency, install with --scope project instead of the default user scope so the plugin stays pinned to the project repository. After marketplace updates, /reload-plugins or claude plugin marketplace update unity-agent-plugin picks up the latest version.

Review results as usual

The plugin does not replace human review. Check generated changes to scenes, prefabs, shaders, localization files, or store configuration like any other agent output — through a diff, a play-mode test, and, where available, automated Unity tests — before they land on a shared branch.