What optional features send

Each feature here sends nothing until you turn it on or use it. Connections, sync and sign-in are on What leaves your device.

AI assistant (off by default)

Nothing goes until you turn it on and choose a provider in Settings › AI, and then only when you ask something.

• It goes to your provider: Anthropic, any OpenAI-compatible service (a local model too), or your Sternway server, which passes it to the service its operator set up.
• It sends your question, a fixed instruction text and, only if you selected terminal text, that selection (at most 8 KiB). Never the scrollback or the rest of the screen. The phone also sends the host’s operating system and shell name when known.
• On the device, Sternway first replaces with [REDACTED] private key blocks, tokens of a known shape, passwords in addresses and command lines, NAME=value where the name says it’s a secret, and the exact values of every password, key and passphrase saved in your vaults.
• With Always preview before sending on (the default), each request shows what will go, hidden secrets marked, and waits for Send.

It misses a secret that’s in no vault and doesn’t look like one, a saved value under 4 characters, and a saved value in another form, such as base64 or URL-encoded.

Leaked-password check (off by default)

With Settings › Security › Breach check for new passwords on, setting your account password asks Have I Been Pwned’s Pwned Passwords service for leaked hashes starting with the same five hexadecimal characters as your password’s SHA-1 hash. Only those five characters go, with padding, and the match is worked out on the device. Host passwords are never checked.

Update check (desktop, off by default)

With Settings › Updates › Allow update checks on, the app downloads the feed (by default https://downloads.sternway.dev/feed/stable.json) a minute after start, once a day, and on Check for updates. No version, platform or id is sent, and nothing is downloaded or installed (Turn on the update check).

Imports from the network (desktop)

• Tailscale runs tailscale status --json on this computer, or makes one request to api.tailscale.com (or your Headscale server) with the key you paste, which isn’t stored.
• An AWS-linked group asks EC2 for running instances at your interval, signed with the access key stored for it on this device.
• Discover devices sends multicast DNS questions on your local network for ten seconds. They stay on that network.

Session sharing

A shared session goes through your Sternway server’s relay, encrypted with a key that’s only in the invite link’s # part, which the server never receives. The server learns who joins (name and email), when the invite ends and whether guests only watch.

Everything else

• Notifications are made on the device, with no push service or push token.
• Links from a terminal or the About page open in your browser after you confirm. The app sends nothing.
• The desktop window can’t load anything from the network. Spell checking is off, so no dictionaries download, and fonts, themes and icons are bundled.
• Backups and exports are files you save. A CSV export holds saved passwords in plain text, and the app says so first.
• Session recordings never leave the device.

This doesn’t cover what your server, its reverse proxy, your AI provider or your network record about requests (such as IP addresses), or requests the operating system, Electron or Chromium make on their own.

Check it yourself

Run the app with no account and every feature off, and watch its traffic with Wireshark, tcpdump, OpenSnitch or your router. You’ll see your own connections and nothing else. Turn a feature on and you’ll see the destination listed for it.