Board Thread:Lua Help/@comment-24473195-20150527141750/@comment-166269-20150527185500

That would be Template:Documentation itself, or one of its subtemplates, and switching to the module version won't prevent it from generating those entries on Special:WantedTemplates/Special:WantedPages. If you want to prevent that, you should instead nab the Wikia-default Template:Documentation and extend it as you need for your wikis (and you definitely shouldn't be avoiding creating /doc subpages; they are wildly useful to the point of being almost required for templates past a certain point).

Note that I'm not arguing that parser functions are a good system; they're not, by any measure. But there are plenty of cases where the logic needed for a template is too simple for a full-blown Lua module to be justifiable, but too complex to achieve with just parameters and parameter defaults, in which case your only alternative is to fall back on parser functions. Basically: parser functions for simple things are incredibly straightforward and handy, while being low-cost; parser functions for complicated things very quickly get out-of-hand in complexity and manageability. =)