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On your machines

Servers and ports

See what’s listening on a machine, and open its web servers at localhost on your computer.

A dev server running on another machine is usually a pain to look at: it listens on localhost there, and you’re here. Muxen lists what each machine is serving and puts any of it at localhost on your computer with one click. No desktop, no ssh tunnel to remember, nothing opened on the network.

Beacon's page: its Servers list with a Vite dev server on port 5173 open at localhost:5173, a noVNC container and a shop app, and 8 other ports folded away. Beacon's page: its Servers list with a Vite dev server on port 5173 open at localhost:5173, a noVNC container and a shop app, and 8 other ports folded away.
The dev server on port 5173 runs only on Beacon. Here it’s open at localhost:5173, and listed under Beacon in the sidebar.

What’s listening

The Servers section on a machine’s page lists every port something listens on there.

  • Web servers come first, with the title of the page they serve (a dev server, a Docker container’s site), the program or container behind them, and their HTTP status.
  • Everything else is folded under “N other ports”: databases, system services, apps’ helpers.
  • “Only on Beacon itself” means the server listens on the machine’s own localhost. You can still open it from here.

The list is read again while the page is open, and the refresh button next to it asks right away.

Open one here

Open on a web server puts it on your computer at localhost, on the same port number when that’s free here, and opens it in your browser. Other ports have Forward instead: the same, without the browser, for a database client or an API tool.

  1. 01

    localhost:5173 here

    Your browser connects to a port Muxen listens on, on your computer only.

  2. 02

    The machine’s connection

    Muxen carries it over the live connection it already has to that machine, ssh or direct.

  3. 03

    Port 5173 there

    The machine’s agent connects to the server, as if you were on the machine.

Nothing is opened to the network on either side.

Because it goes through Muxen’s own connection to the machine, it works the same over ssh, over a direct connection, at home or through Tailscale.

  • An open port is listed under its machine in the sidebar, as localhost:5173. Click it to open it in your browser again.
  • × next to it (or Close on the machine’s page) stops it here. The server on the machine keeps running.
  • Open ports come back when Muxen starts.
  • When the server on the machine stops, Muxen closes it here and tells you.

Any port

Something not in the list yet, say a server you’re about to start? Type its number into Open a port above the list and press Return.

Looking at it in a browser on the machine itself instead? That’s what Desktops are for. For a web app you’re building, opening it here is usually quicker and sharper.

On Windows

Windows’ own web server holds a few ports for its services (device discovery on 5357, remote management on 5985) and answers anything else with an error page. Muxen doesn’t list those as servers.

From a terminal and from agents

muxen ports beacon         # what’s listening there, web servers first
muxen forward beacon 3000  # its port 3000 at localhost:3000 here, until Ctrl-C

Agents get the same list with machine_ports. To check a server from the machine itself, they can run curl -sS localhost:3000 there with workspace_exec. See MCP for your agents.