When creating adding a references list to an article, we always add a References header if it doesn't exist yet.
The References list tool should do it for us.
- Create a References header
- Insert > References list (to add the References list)
- Insert > References list (to both create a References header if not existing and add the References list)
This is actually a feature of the wikitext editor standard toolbar on :en and :fr wikipedias: