auctex: Itemize-like
2.4.3 Itemize-like Environments
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In an itemize-like environment, nodes (i.e., '\item's) may be inserted
using 'C-c <LFD>'.
-- Command: LaTeX-insert-item
('C-c <LFD>') Close the current item, move to the next line and
insert an appropriate '\item' for the current environment. That
is, 'itemize' and 'enumerate' will have '\item ' inserted, while
'description' will have '\item[]' inserted.
-- User Option: TeX-arg-item-label-p
If non-nil, you will always be asked for optional label in items.
Otherwise, you will be asked only in description environments.