Hlid (Old Norse hlið: a gate in a wall — the gate itself, not the wall and not the road beyond it). The lifecycle of an ephemeral public gate, held as pure state: minted, guarded, handed over as an address, and destroyed, with "between meetings the door does not exist" as a constant rather than a comment. It opens nothing. A single-gate guard refuses a second minting while one stands, before the machine is touched at all; the address is taken as the FIRST match of the opening script's own pattern read out of a log, and the number of polls that pattern was looked for is counted by the water and named in every refusal, because the water holds no clock — the machine's poll IS the tick. The room name is the key and so is validated as a URL path segment and refused otherwise, a key that does not survive a URL being no key. The tunnel itself belongs to a declared host of three verbs — spawn, poll, kill — which this water implements nowhere: it owns no process, no executable, no socket, no file and no clock, the binary's path is the host's argument, and there is no address anywhere in it to pull a binary from. The gate state is a plain serialisable object the shell keeps. Nothing throws; every failure is a refusal carrying one sentence.
Old Norse hlid (a gate, an opening in a wall or fence), naming the gate itself rather than the wall it opens or the road beyond it.
The lifecycle of an ephemeral public gate held as pure state: minted, guarded, handed over as an address, and destroyed. Between meetings, the door named by this word does not exist.