libtmux.neo.SCOPES_BY_LIST_CMD

A token whose scope is in the set is safe to include in that subcommand's -F template. A token whose scope is *outside* the set may be unavailable for that command, so libtmux leaves it out.

The relationship is asymmetric: when tmux lists a parent object, it can also report fields for that parent's active child. A session row can include its current window and active pane fields, and a client row can include the attached session, current window, and active pane. client scope is the exception in the other direction: it appears only in list-clients because session/window/pane listings do not have a client attachment to report.