mods such as creative-mod mode add "cheat" recipes that have no ingredient. suggest blacklisting productivity research for any items that have no cost.

Note: this particular interaction may only occur / be more significant when other mods alter recipes that permit productivity, or otherwise nullify module restrictions.

(also, be careful about how the check/blacklist is performed), interactions may create scenarios where there is a disabled/hidden recipe that has no ingredient, but a new recipe for the item that does. probably want to only reject adding research effects for those recipes that do not have an ingredient, rather than rejecting researches if [ any] recipe exists for said item that has no cost.

Currently, the mod excludes all hidden recipes, but not necessarily their items. In other words, if at least one non-hidden recipe for an item exists, a tech will be generated for the item.

With regards to your first point, I wasn't aware of "no cost" recipes, but I will add a check to exclude them automatically. Thanks.

It's now implemented with settings to enable recipes again, if required.