Accordance puts tools in one of five folders based on how the tool is organized. English Tools are base on the English alphabet, so they include Bible dictionaries (entries appear in alphabetical order. Greek and Hebrews Tools follow their respective alphabets, so consist of lexicons. Reference Tools are set up by biblical references, so things like commentaries, apparatuses, are in this group. Everything else goes in General Tools.
What befuddles new Accordance users is the allocations of Greek and Hebrew grammars. They are General Tools because they are not arranged alphabetically. It is not obvious on the surface, but it is logical and consistent. Furthermore, Accordance will not let you move them to a different Tool folder. If it really bugs you, you can create your own organization of tools under My Groups. There your folders can mix tool types.