The problem of insufficient development of professional digital tools in the humanities, including linguistics, is posed. The results of a long-term study on the development of specialized software for corpus analysis of a foreign language text, in which the regional component plays an important role, are described. On the example of Franz Kafka’s novel “Das Schloss” the work of three computer programs is demonstrated, including primary text processing, automatized markup of a small special (grammatical) corpus, a combined search for selected constituents of the grammatical categories of certainty / uncertainty, modality, as well as individual grammatical phenomena by markers of the marked up corpus and by regular expressions in case of the not marked up text, considering the regional characteristics of spelling. It is concluded that the maximum effectiveness of research of this kind can be achieved with the active work of an expert with a specially developed software product. Moreover, the expert’s task includes not only professional software management, but also active participation directly in its development. The described analysis model can be used to analyze the categorical spectrum of a foreign language text, as well as to compile didactic materials for teaching foreign languages ​​and translation.