Machines & the agent host

The agent host is a small daemon that runs on your own computer. It's the half of UFO that does the work: your agents execute here, with real terminals, files and a browser, driven by whatever model you configured. The workspace — the website and apps — is just the cockpit you drive them from.

The host runs on macOS (Apple Silicon), Linux (x86_64) and Windows (x64). Quickstart walks through installing it; this page covers pairing, running it as a service, and how it keeps itself healthy.

#Pairing a machine

Pairing works like signing a smart TV into an account. The installer shows a short device code, you approve it once in the browser, and the machine's tokens write themselves — no copied-and-pasted API keys.

Codes are single-use: if one expires or gets mistyped, just run the installer again to get a fresh one. And there's one authoritative machine per workspace — when you pair a replacement, the old machine's tokens retire automatically and its agents move over to the new one on their own, so swapping hardware isn't a re-setup.

#Run it as a service

Setup registers the host to start automatically on boot, on all three operating systems, so it survives reboots and comes back after a crash. You manage it with a couple of commands on the host:

# is the background service running?
ufo service status

# (re-)register auto-start
ufo service install

#Check its health

ufo doctor is a 10-check self-diagnosis. It verifies config, pairing, live server reachability, your engines, Node, per-OS computer-use tooling, service liveness and auto-start — and prints the exact fix for anything it flags.

# run on the host machine
ufo doctor

Run it any time the host seems off; it's the fastest way to a green machine.

#Self-updating, zero downtime

The host upgrades itself in the background. Updates are rolling and hitless: in-flight conversations finish on the running version while every new message is handled by the newest one, so you never restart anything by hand.

It's also self-healing. If a bad build crash-loops, the host automatically rolls back to the last known-good version instead of leaving you with a dead daemon.

#Machine status

Each paired machine shows a status dot in Settings → Machines, so you can see at a glance whether the host is online.

That dot matters because of one honest trade-off: agents run on your compute. If the host machine sleeps, your agents sleep with it. Leave it awake, or dedicate a small always-on box, and the crew stays available around the clock. If you'd rather not keep a machine on, UFO Cloud runs a managed host for you instead.

#Where to go next

• Quickstart — install and pair the host in about a minute.
• UFO Cloud — a managed always-on host, no computer to keep awake.
• Troubleshooting — fixes when a machine or agent goes quiet.