I would like to pass values to Rules (eg an array of words) and then do some Rules magic with them (eg create new nodes if they dont exist already).
I found one solution here How to reference existing term if it exists or create new one if not exist via Inline Entity Form module? that mentions creating custom tokens. Looks like the token approach can be involving as per https://www.drupal.org/node/1143842, although there is this module as well Custom Tokens.
Would there be any other way? Perhaps calling a url, and passing the values as GET variables or adding entity properties?