Why not Termius or Blink
A general SSH client assumes you opened it to type commands. Agentmux assumes you opened it to rejoin an agent that is already running. Take Termius or Blink if you need Mosh, SOCKS5 forwarding, or host sync across platforms. Take Agentmux if your work is coding agents on several servers rather than one-off commands on one host.
Both apps speak SSH and both hand you a prompt. What separates them is how much thought went into reattaching, and every row below follows from that. The five capabilities described here are all checked against the current source.
Two tools built on different assumptions
A general SSH client is built around a host and a shell: it hands you a working prompt, then stays out of the way. What happens after that prompt is yours.
Agentmux is built around an agent that is already running somewhere. Its job is to shorten the distance from your pocket to that process. Three consequences follow, and the last two are where a good general client stops being a substitute. That is not a build-quality problem: those behaviours were never its product.
- What you see first. A host, or the sessions running on it.
- What a dropped connection costs. A prompt you re-navigate, or the screen you left.
- What the app does while you are away. Nothing, or a Lock Screen progress line and a sound at the end.
What each one does, capability by capability
One row per capability. Where you cannot check a competitor's behaviour from outside its app, the cell says so.
| Capability | General SSH client | Agentmux |
|---|---|---|
| Back to a tmux session | tmux ls, then tmux attach -t |
Sessions listed on connect; one tap reattaches |
| After a drop | The prompt returns; finding the session is on you | A detach, not a death: you land on the screen you left |
| A twenty-minute agent run | No notion of a run to report from | Dynamic Island and Lock Screen progress; a sound at the end |
| Prompt to allow a command | You are the reviewer, in the chair | AI Permission Review: blacklist, allowlist, AI judgement; suggests or presses the key (Pro) |
| One line in a file | Vim over SSH, on a phone keyboard | Runestone editor, Ink Markdown preview, branch tools, Files app (Pro) |
| Private keys | Not verifiable from outside | Keychain / Keystore, never the local database; iCloud sync carries server names only |
| Automation from outside | Nothing to call: no session or agent model exposed | 6 App Intents over four entity types: Server, Project, TMUXSession, RecentSession |
| Unreliable mobile networks | Mosh is a reason to buy this kind of app | Standard SSH plus tmux reattachment, which is not Mosh |
| Port forwarding | Local, remote, dynamic SOCKS5 | Local only |
| Host configuration at scale | Synced on iOS, Android, Windows, macOS, Linux; shared host lists | Multiple servers and batch actions (Pro); mobile only |
Read the last three rows first: they are where Agentmux loses.
Why does Agentmux list tmux sessions first?
Connect to a server and Agentmux lists the tmux sessions already running on it. One tap reattaches, so you do not type tmux ls or remember tmux attach -t. Reconnect after a drop and you land on the same session, on the screen you left, without retyping anything.
An agent's value is the context it accumulated: which files it read, why it chose this approach. Reattach to that screen and the context survives. Open a fresh prompt and you explain the task again to a process that has forgotten it. What tmux does is the load-bearing part of this design.
What does the app do while you are away?
Agents routinely run for tens of minutes, and that waiting period is what this is built for. The Dynamic Island and the Lock Screen show progress, and a sound can play when the run ends. The app does not have to sit in the foreground while you stare at it.
An app built around a shell has nothing to report once it is closed, because it holds no notion of a run. Here a named session on a named server is running, and the system reports on it. When that session stops to ask whether to allow a command, AI Permission Review can look first: dangerous commands are held, safe ones get a suggestion or a key press (Pro).
Can you edit a file without opening vim?
Changing one line of code does not mean wrestling vim on a phone keyboard. The built-in Runestone editor opens the file and lets you edit it. For a README an agent produced, Ink gives a two-column Markdown preview, source and rendered side by side. Git tools (switching branches, reading diffs) and Files app integration are Pro features, available during the 14-day trial.
The loop closes on one device: the agent changes files, you read the diff, you answer, it goes on. Every step that needs a second machine waits for a desk.
Where do your private keys live?
Private keys go into native secure storage, the iOS Keychain or the Android Keystore, and never into the local database. On iOS, if you turn on iCloud sync, CloudKit carries non-sensitive metadata such as server names. The keys stay where they are.
Ask any tool the same question: which of my private keys leave this device when sync is on? A feature list will not answer it.
Siri can hand the screen to Shortcuts
GetCurrentSessionContextIntent lets you tell Siri "get the current terminal contents from Agentmux". Whatever is on the terminal lands in iOS Shortcuts, ready for Notes, Messages, or anything else you build. ContinueLastSessionIntent is blunter: "continue working in Agentmux" reattaches to your last session.
General SSH apps cannot do this, structurally: they have no semantic model of sessions, projects, and agents to expose to the system. Agentmux implements 6 App Intents across four entity types: Server, Project, TMUXSession, RecentSession.
Fixes you'll feel if you read CJK
Version 1.3.10 fixed three things an English-only user never notices and a Chinese, Japanese, or Korean reader spots at once: selection drifting out of alignment on full-width characters, a link that wraps across lines copying out as several separate pieces, and a lone slash inside CJK text read as a file path.
Which tool for which job?
Mostly manual terminal work on one host. You log in to run commands you chose: restart a service, tail a log, check a disk. Take a general SSH client. If you want to test the idea first, the free single-server tier covers one server, persistent sessions, and the core terminal.
Living inside agents on several servers. One refactoring on the Mac mini, another running tests on a Linux box, a third started from a train. That is Agentmux, and specifically Pro: multiple servers, custom agents, remote editing, file history, branch tools, batch actions.
An agent in a browser tab or a cloud sandbox. The convenience is real, and the cost is that the files and the credentials no longer sit on your machine. Agentmux never hosts the work: it is a client, and the code and the agent stay on hardware you own, a Mac, a Linux box, or a server. Renting one is defensible if you are at peace with your project and its keys living there.
Tailscale is the recommended way in: no port open to the public internet, and machines addressed by MagicDNS names or 100.x addresses rather than LAN IPs.
When Termius is the better buy
If one of these is your main job, buy the general tool.
- You work on very unreliable mobile networks and need Mosh to hold the connection. Agentmux speaks standard SSH and compensates with automatic tmux reattachment, which is not the same thing as Mosh.
- You need remote or dynamic (SOCKS5) port forwarding. Agentmux only does local, and that is a capability gap rather than a preference.
- You want to sync a large host configuration across iOS, Android, Windows, macOS, and Linux, or share a host list with a team. Agentmux is a mobile client: multiple servers and batch actions on Pro, nothing shared.
- You are an SRE or sysadmin running operations across dozens or hundreds of servers. An inventory you script against beats a list you tap through.
Agentmux is built for one workflow: rejoining a running coding agent from your phone. It is not a general-purpose operations tool. If your week is a stream of one-off commands, there is nothing here worth switching for.
Decided on Agentmux? The next problem is the machine at the other end: the setup wizard asks three questions and hands back a checklist, and most of what goes wrong afterwards is already in troubleshooting.