The hypothesis of a bandwidth/fidelity trade-off among personality-descriptive categories that differ in level was investigated for 25 personality-descriptive categories. Two measures of inclusiveness, a rating of category breadth and the grammatical form of the category descriptor (verb or adjective), correlated substantially. Bandwidth and fidelity of the categories were measured by analysing the distributions of prototypicality ratings in a sample of naturally occurring activities. It was found that broad categories refer to more exemplars than narrow categories, whereas the exemplars of narrow categories are more prototypical. Such a bandwidth/fidelity trade-off however, is not found for adjectives and verbs. Rather, adjectives have a lower fidelity but not a broader bandwidth than verbs, and they are therefore the less informative behaviour descriptors.