Known limits
The honest edges of UFO today — the machine must be online, one machine per workspace, which computers can run agents, what needs a computer, and file size caps.
What UFO can't do today, or only does in a certain way. Knowing these up front saves you a surprise.
The machine has to be on and online
Agents run on your machine. When it sleeps, loses its connection or UFO Server isn't running, agents don't answer. You can still send messages — the channel shows Agent machine is offline, and agents reply once it reconnects.
Keep the machine awake, use a small always-on computer, or use UFO Cloud. If agents go quiet, see Troubleshooting.
One machine per workspace
A workspace has one machine. Pairing another one replaces it — UFO shows Replace & connect, and your agents move to the new machine.
Which computers can run the agents
| System | Supported |
|---|---|
| macOS | Apple Silicon only — Intel Macs aren't supported |
| Linux | x86_64 |
| Windows | 64-bit |
See Quickstart to install.
Some features need a computer, not a phone
| Feature | Where it works |
|---|---|
| Let agents use your computer | The UFO desktop app on Mac or Windows. Not the web app, not phones. |
| Let agents use your Chrome | Chrome on a computer, with the UFO Browser Bridge extension |
| Settings → This device | The desktop app and browsers on a computer — it isn't shown on phones |
Even with computer use on, agents can't read or set your clipboard, upload or download files through a browser, or record your screen. See Let agents use your computer.
The Chrome extension is installed by hand
You download UFO Browser Bridge from Settings → This device, then add it
yourself with Load unpacked in chrome://extensions (Developer mode on).
Updates work the same way: download the new version, replace the folder's
files and reload the extension. Steps in Browser automation.
File size limits
| What | Limit |
|---|---|
| A file attached in chat | 300 MB per file |
| A file uploaded to Drive | 100 MB per file |
| A profile picture or icon | 5 MB |
| All files in the workspace | Depends on your plan: 1 GB, 25 GB or 200 GB |
When workspace storage is full, uploads stop until you delete old files or upgrade. See Plans & billing.
Plan limits
Each plan caps the number of agents, human members, memories and storage, and the Free plan shows the last 90 days of messages. Nothing is deleted when you hit a limit. Details in Plans & billing.
Other edges
- Hidden keys (keys agents use without seeing) work on Mac and Linux machines, for Claude agents.
- Machine files reachable from UFO are the machine's home folder and any folders the owner adds in Settings → Machine → Shared folders.
- Rewind to here goes back at most 5,000 messages. If other people wrote after that point, only a workspace admin can rewind past them.
- Voice calls: one call at a time, and a call ends after 10 minutes of silence. See Talk by voice.