The present research investigates how mediation occurs in the triad student- tutor-advisor in distance education for building autonomy and student authorship during the elaboration of the Final Course Assignment (FCA). We assumed that the appropriation of scientific concepts in specialization courses by the Open University System of Brazil (UAB) does not occur in isolation but through the intentional intervention of tutors and advisors. These teachers would contribute to the building of theoretical thinking, a founding element of academic autonomy and authorship for writing the FCA. We based the study on the historical-cultural approach, and the methodology converged with this referential. We applied: 235 online questionnaires to alumni who completed specialization courses at UAB, in several states and institutions; four online focus groups (OFG) for tutors and advisors, reaching 24 participants; and seven interviews with teachers who were not able to participate in the OFG. We analyzed the collected data using three thematic axes: autonomy, authorship, and mediation. The results showed at least two factors that the triad points out as essential for writing the FCA: the available time and the observation of academic and ethical norms. While for the former students the time factor was associated with the availability to dedicate themselves to the studies, for the teachers, it was related to the insufficient given period to carry out the necessary mediation to assist students in their FCA. We conclude that the participants sensed academic autonomy as a prerequisite for initiating FCA rather than as a building process that occurs along with the writing. Participants pointed to the need for closer follow-up with the students, including clarity and agility in feedback, while sustaining affectivity. The concrete and objective conditions that go through the development of the FCA did not allow participants to prioritize teaching interventions for students improvement and development of theoretical thinking. Nevertheless, in seeking to overcome the alienation (LEONTIEV, 2004) of these conditions, they were able to conclude their work, by finding a way to alleviate the difficulties emerged during the authorial writing of the scientific works.