The quality of a written text is often described in figurative terms, such as clearness and smoothness. The explicit description of what makes a text clear and smoothly flowing is a challenging task, probably because the readers’ perception of a text is influenced by multiple variables, related to the way information is structured, and how the writer employs the lexical and morphosyntactic resources of a language. The difficulty in translating the readers’ perceptions of a text in measurable descriptors leads to challenges in literacy education. For instance, how can educators explain what makes a text clear and smoothly flowing? What are the crucial aspect to focus on when giving feedback or conducting formative assessment? Answering these questions is of fundamental importance, given that writing literacy may have a considerable impact on employability, social participation and lifelong learning. This project aims to explore the relationship between the holistic evaluation of texts, carried out by expert evaluators, and their linguistic characteristics, to understand to what extent it is possible to identify objective and measurable properties that distinguish texts perceived as well written, compared to those with less positive ratings. For this purpose, we will establish a corpus of argumentative and narrative texts, written by university students, who are L1, L2 (or L3) speakers of Italian, a language that has received little attention so far in international research on writing. The methods of analysis involve the use of linguistic indices identified by previous research, which focus on the lexical and morphosyntactic complexity of the texts, and their integration with new indices, based on the Basel model of text analysis. This model contributes to a deeper understanding of the architecture of a text, by analysing how information is structured and hierarchized, and how textual units are connected on different semantic-pragmatic levels.