Working in a upool slot

A pooled Unity project gives each session a slot: a clone of the checkout, with a warm Library, at
<repo>/.claude/worktrees/slot-N. UNITY_PROJECT_PATH names your slot. upool which prints the
slot your working directory is in, and exits 1 outside every slot.

Target your own slot

• unity command, status and recompile follow UNITY_PROJECT_PATH. Never unset it: with one
  Editor running and no variable, a call goes to that Editor, whichever slot it is in.

• unity test, run, build, close and cache key ignore the variable. Pass it as their
  project argument; without one they fall back to the working directory, or fail with "Not a
  Unity project":

  unity test "$UNITY_PROJECT_PATH" --mode EditMode
  unity cache key "$UNITY_PROJECT_PATH"

Save, then close

Run unity command save_all before unity close "$UNITY_PROJECT_PATH". close exits without
saving and without asking, so unsaved scene changes are lost.

Scenes

• Never hand-edit scene or prefab YAML (*.unity, *.prefab) while a live Editor is reachable for
  the slot. Make the change through the Editor, or save and close it first.
• After a headless session, open your scene explicitly. A batch run leaves the Editor's last scene
  list empty, so the next Editor opens on an Untitled scene rather than yours.

After a timeout

A Unity call that times out may still have run, especially the first call to a newly opened Editor.
Re-query before retrying: check for the change it was to make (the file, the object, the state)
with unity status or a read-only unity command eval, and retry only if it is not there.

Subagents

A subagent works in a plain git worktree, not a slot. One that needs Unity takes a slot of its own
and releases it itself. From anywhere in the repository:

upool take <branch>     # prints only the slot's path; <branch> is created if it does not exist

Use that path on every Unity call, UNITY_PROJECT_PATH=<slot> unity command … and
unity test <slot> …, since a shell variable may not last from one command to the next. Commit
your work to the branch, then upool release <slot>: release resets a clean slot for the next
session and parks a dirty one.