Unity CLI Loop skill
The uloop CLI and 21 skills let an agent build, test and run a Unity project, read logs and check the game in Play Mode.
- 598 ★ on the repository
- Last commit
- MIT
Broad access
Why this level
- `execute-dynamic-code` runs arbitrary C# in an open editor without confirming each command.
- The agent changes scenes, assets and project code and presses keys and buttons in Play Mode.
- To work, the CLI needs `uloop *` excluded from the Claude Code sandbox.
Install
- Works in
Manual install
curl -fsSL https://raw.githubusercontent.com/hatayama/unity-cli-loop/main/scripts/install.sh | shThe first README option for macOS, Linux and Git Bash. Then `uloop package install` and `uloop skills install --claude`.
Access and checks
How we reviewBroad accessThe tool can change data, run commands or handle secrets.
- `execute-dynamic-code` runs arbitrary C# in an open editor without confirming each command.
- The agent changes scenes, assets and project code and presses keys and buttons in Play Mode.
- To work, the CLI needs `uloop *` excluded from the Claude Code sandbox.
This is third-party code. Review the repository files before installing.
What it does
Unity CLI Loop connects an agent to a running Unity Editor through the `uloop` command. The agent compiles the project, runs tests, reads console logs, gets the scene hierarchy, captures window screenshots and controls Play Mode. Dedicated tools cover what code cannot: `hot-reload` applies method-body edits without recompiling, `pause-point` stops the game on a line and returns local variables, `simulate-keyboard` and `simulate-mouse-input` send input in PlayMode. `execute-dynamic-code` takes the rest by running C# in the editor. `uloop skills install --claude` or `--agents` installs the skills.
Who it is for. Unity 2022.3+ game developers who hand the agent the loop of edit, compile, test and Play Mode check.
Good fit when
- The agent edits C# and every change needs a compile and a test run without a person.
- A test fails and the cause is traced through console logs and variables on a given line.
- UI is compared with a Game View screenshot and the layout is adjusted.
- A new mechanic is checked in Play Mode: the agent presses buttons and replays recorded input.
Not a fit when
- The project is not on Unity 2022.3 or newer.
- The agent must not run arbitrary C# in an open editor.
- The Unity Editor cannot be launched on the machine.
Example request
Fix the compile errors, run the EditMode tests and show which ones failed and why.Limitations
Unity 2022.3 or newer is required. In the Claude Code sandbox `uloop` fails with `UNITY_NOT_REACHABLE` until `uloop *` is added to `sandbox.excludedCommands` in `~/.claude/settings.json`. `focus-window` is unavailable on Linux; the README lists the CLI installer for Linux x86_64. After upgrading from V2, custom C# tools fail to compile until migrated. The installer runs through `curl | sh`, so read the script first.
How to disable. Delete the `uloop-*` skills from `.claude/skills` or `.agents/skills`, remove the `io.github.hatayama.uloopmcp` package from `Packages/manifest.json` and the `uloop *` line from `sandbox.excludedCommands`. The CLI is removed with the Uninstall CLI button in the Settings window.
FAQ
How do I install it for Claude Code?
Install the CLI, then in the project root run `uloop package install`, `uloop launch` and `uloop skills install --claude`. For Codex and other tools use `--agents` instead of `--claude`.
Why does `uloop` fail to connect in Claude Code?
The sandbox blocks the connection and the command fails with `UNITY_NOT_REACHABLE`. Add `uloop *` to `sandbox.excludedCommands` in `~/.claude/settings.json`.
Do I need to open ports?
No. The link uses a Unix domain socket on macOS and Linux or a named pipe on Windows, so no ports need configuring.
What does `hot-reload` do?
It applies method-body changes to running code without recompiling while the game stays in Play Mode.
How many skills are bundled?
Twenty-one, from `uloop-compile` and `uloop-run-tests` to `uloop-pause-point` and `uloop-replay-input`.
Discussion
No questions or reviews yet.
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Comparison with similar tools
Cards that share the main search query, and how they differ.
| Tool | Official | Authentication | Repository stars | Main difference |
|---|---|---|---|---|
| Unity CLI Loop (this card) | no | 598 | ||
| MCP for Unity | no | not required | 15,902 | connects the editor over MCP; Unity CLI Loop works through the `uloop` command and skills |
| Unity MCP Server | no | not required | 542 | exposes MCP tools for scenes and builds; here a CLI and 21 skills drive the same loop |
| Unity Skills | no | 1,244 | the official Unity knowledge set for agents; Unity CLI Loop adds control of a running editor |
README in short
The chain is the global `uloop` command, a per-project runner pinned by `.uloop/project-runner-pin.json` and an IPC server inside the editor. Several projects on different versions coexist on one machine.