options(citezot.key_format = "auth.lower + year")
cz_key_format()$formula
[1] "auth.lower + year"
$source
[1] "option"
In order: getOption("citezot.key_format"); the Better BibTeX pattern in your Zotero profile (see Details); Better BibTeX’s default pattern.
Detection of the Zotero profile reads one line of its prefs.js and only happens when a key is generated, never at load. Set options(citezot.key_format = ...) to choose a formula yourself and skip the detection, and options(citezot.zotero_profile = "<folder>") if Zotero keeps its profile somewhere unusual. The source in use is reported once per session.
A list with formula and source ("option", "zotero profile" or "default").