Authentic assessment is often narrowly framed as tasks that mirror workplace tasks, resulting in on overemphasis on generic workplace skills at the expense of disciplinary knowledge. We place disciplinary knowledge at the heart of authentic assessment and explore how authentic assessment across a programme can contribute to an authentic view of the broad discipline of science. Through the metaphor of a suspension bridge, we explore relations between disciplinary knowledge, the nature of the discipline, feedback from assessment, and evaluative judgment. We argue that assessment of student reflection on the nature of science is an essential but often overlooked element of authentic assessment and provide data to support this claim. Critical reflection on the nature of science invites students to examine and question their worldview assumptions about what science is and how it works, giving them the epistemic agency to deeply engage with the often-controversial ways science interacts with society.