Asset number. Used in legacy subjects and as the last source ID fallback.
Optionalbox_Edge box ID, the <box> token of structured subjects.
Optionallabjack_LabJack name. Used as the source ID when source_id is empty.
Root subject token, such as avenabox (legacy) or avenars (structured).
Optionalsite_Site ID, the <site> token of structured subjects.
Optionalsource_Source ID, the <source> token of structured subjects.
Optionalsource_Source type. Kept for config compatibility; no builder here reads it.
Fields of a LabJack config (KV bucket
avenabox) that name its subjects.