How to check for score/tag in advancement .json

quick question: i need to add a requirement to an advancement that checks for a specific score or tag. i heard that tags are easier to use in advancements but i dont know how to implement them. 
I have an advancement here that requires the player to craft a stone pickaxe. I now want to add a second requirement that checks if the player has a score of inventory_is_full == 0. or if tags are better then just check for the tag inventory_has_space or something like that