Unity CLI Loop by hatayama, now called Unity Loop Harness, is an open-source CLI with agent skills for compiling, testing and playing Unity projects.
Unity CLI Loop gives your agent a CLI and skills for compiling and testing. Satura Space gives it the running game, and adds the four features below.
The agent sets up the moment and opens Unity's real Inspector on just the fields that matter. You tune it by feel.
Run agents in parallel, each in its own side Unity project, streamed beside the game. Open a Tuner on any of them.
Up to four synced editors, each streamed with its own input. One handle call starts every player on the same frame.
Ask about anything you don't know. Drift walks you through the UI, points at the field and explains what to tweak in the Inspector.
| Satura Space | Unity CLI Loop | |
|---|---|---|
| The Tuner: an Inspector scoped to what matters | ✓Yes | ✕No |
| Ask Drift: a guide that points at the field | ✓Yes, in alpha | ✕No |
| Parallel agents in side projects | ✓Scratchpads, one Unity each | ✕Not listed |
| Multiplayer testing | ✓Four synced editors | ✕Not listed |
| The running game, beside the agent | ✓Streamed, with your input | ✕Screenshots and recordings |
| Agent plays and checks its work | ✓Handles, video and a report | ✓Input, tests, logs |
| Screenshots and video | ✓Both, 60 fps video | ✓Both, MP4 video |
| Play Mode control | ✓Yes | ✓Play, stop, pause |
| Run C# in the editor | ✓Yes, unity.exec | ✓Dynamic C# |
| Run tests | ✓Yes | ✓Edit and Play Mode |
| C# hot-reload in Play Mode | ✓Method bodies | ✓Method bodies |
| Unity runs hidden | ✓Yes | ✕Not listed |
| Your own agent (which ones) | ✓CLI agents | ✓Claude Code, Codex, Cursor, others |
| Works inside your IDE | ✕No, desktop app; Cursor connects over MCP | ✕Not listed |
| Open source | ✕No | ✓Yes, MIT |
| Unity versions | Unity 6 only, Mono | 2022.3 and later |
| Platforms | macOS Apple Silicon, Windows x64 | macOS, Windows, Linux |
| Price | $19/mo, $15 annual, 7-day trial | Free, MIT |
Yes, it is MIT-licensed. You still pay for your agent. Satura Space is $19 a month, or $15 billed annually, with a 7-day trial and no card.
Yes, it applies method-body changes to running code. Satura Space does the same in Play Mode.
Yes. Satura Space registers its Unity MCP server for Claude Code, Codex and Cursor automatically, and any MCP client can be pointed at it.
Try it for seven days. No card needed.