Twelve Launches From a Tab
Written later and filed to this date, as part of filling in every day of the year.
The phone said its sessions were dying. They were coding sessions opened from my phone through a host process on the box, and the word was the phone’s, not mine: the app showed each one as a live link and then, some evenings, showed them all gone at once.
The host had been started by hand. Open a terminal tab, type the command, leave the tab. Everything the phone opened after that was a child of that command, and children share their parent’s terminal session. Close the tab, let the terminal die, or log out of the desktop, and the kernel sends the hang-up signal to the whole set in one stroke. From the phone it looked like an outage. From the box it was the ordinary consequence of starting a long-lived process from a seat you occasionally leave.
The shell history shows the shape of the misdiagnosis. Twelve launches of the host by hand, four of them back to back. The four are what you type when the previous host is still alive: the new one exits at once with “Another claude remote-control instance is already running in this directory”, and the reflex is to type it again. Nothing restarted the host when it died and nothing logged that it had, so each loss was investigated from the phone’s side, where the evidence is a missing session and not a signal.
The fix, on a Saturday in early September, was not a smarter host. It was a seat nobody leaves. A service now runs the keeper that already supervised my always-on terminal session in a second mode, for the host: its own multiplexer socket, its own debug log, a wait behind any host a human has already started so two never run at once, and a ladder with one rung. The rung respawns only when the host has left a definitive dead marker, under a cooldown, and never on the outage backstop, because the host can spend hours rebuilding its own transport and killing it mid-rebuild is a second outage. Panes stay open after an exit so the reason lands in the journal instead of vanishing with the pane.
The rule that came out of it is one sentence in the workspace’s root document, in the list every session reads first: “Never start claude rc by hand: it dies with its terminal and takes every session it served.”
The sentence is about who owns a process. A thing started from a tab belongs to the tab. The twelve launches were twelve attempts to own it by hand, and the four typed in a row were the hand finding out it could not tell whether the last one had died.