How can I list all Twig functions and filters with their description? I want a list of all available Twig filters and functions and for each one of them I need to have a description of the function/filter so the user can see what functions and filters are available and how to use them in templates.

I know how to get the list of functions and filters(How to get all filters and functions available in Twig templates?) but I don't know how to get their descriptions.

I don't know how to find out in which file the filter/function resides so I can parse it for the description of the function.
https://api.drupal.org/api/drupal/core%21lib%21Drupal%21Core%21Template%21TwigExtension.php/class/TwigExtension/8 Twig functions have no descriptions. You can run getCallable on a twig function/filter object and then do $reflection = new \ReflectionFunction($callable); $doxygen = $reflection-&gt;getDocComment() to get the doxygen which is the closest to "description".