This study focuses on analysing a teaching practice, carried out by the author of this study, during a period of using visual programming in programming teaching, described according to the Multimodal Narratives model, at the University of Trás-os-Montes e Alto Douro. The central question of this study is to identify the constraints that can arise when using visual programming as an epistemic tool to improve the learning of programming and the consequent development of computational thinking. The data was analysed based on dimensions and their respective categories, depending on how long the teacher and student had been using the visual programming platform. The results point to some constraints explained by the application of a task that conditioned autonomy, and the time dedicated to the most demanding phases, not allowing students to be agents of their own learning. In this study, there was also no teacher mediation in situations of greater cognitive demand, which resulted in moments of inactivity. This study provides significant observations to improve the application of visual programming as an epistemic tool, as well as a solid basis for future lines of research.