AI agents

Composery runs an SSH service, so an instance is a machine an AI agent can be pointed at. The agent runs in it: your files, your terminal, your installed tools, your running services - not a copy of them, and not a sandbox that disappears.

Two desktop applications can take an SSH host and work in it today: Claude Desktop and ChatGPT Desktop. Both read your ~/.ssh/config, so once an instance has an entry there it appears in each of them.

Everything else that speaks SSH reaches an instance too - a terminal, scp, rsync, git, JetBrains Gateway, a desktop editor's remote mode. Those are not special-cased here; they need no instructions beyond a working ssh command.

The fast way

On a Composery Cloud instance, open your box's page and choose Connect remotely. In a self-hosted editor, run Composery: Connect Over SSH from the File menu or the command palette.

Either one gives you a prompt to paste into the agent. It generates its own keypair on your machine, asks the instance for a certificate, writes the ~/.ssh/config entry, and connects itself. You never handle a private key, and the only secret in the prompt is a token that works once and expires in minutes.

The manual way

Add your public key to the instance first - ~/.ssh/authorized_keys from the editor's terminal, or COMPOSERY_SSH_AUTHORIZED_KEYS before it starts - then add an entry to your own ~/.ssh/config:

Host composery
  HostName your-instance.example.com
  User user
  Port 22
  IdentityFile ~/.ssh/composery
  IdentitiesOnly yes
  ServerAliveInterval 30

Check it with ssh composery true before going near either app. Both of them read this file, so an alias that does not work in a terminal will not work in them either.

Claude Desktop

Settings → Compute → SSH hosts → Add SSH host, then pick the alias. The address, user, port and any ProxyJump come from your ~/.ssh/config; User, Port and the identity file can be overridden under Advanced settings.

Claude Desktop installs Claude Code on the instance itself the first time you connect - you do not install it, and the editor's own Set Up an AI Coding Agent card is not a prerequisite. The remote machine has to run Linux or macOS, which a Composery instance does.

The host notes field is worth filling in. Claude reads it before its first job, so this is where to say what the instance already has and what it may install.

ChatGPT Desktop

Settings → Connections, add or enable the SSH host, then choose a remote project folder. The connection starts and manages a Codex app server on the instance over SSH, and the session then uses that machine's projects, files, credentials and tools rather than your laptop's.

Why a persistent machine matters here

An agent working over SSH keeps running when you close the lid. Start a long job, disconnect, and reconnect later to the same instance with the same processes and the same state - tmux is installed for exactly this. That is the difference between a computer you own and a session that ends with the tab.

Revoking access is one line, and it takes effect on the next connection:

composery ssh list
composery ssh revoke <serial>

On Composery Cloud the same list and its Revoke buttons are in the Connect remotely dialog.