Effective feedback can build self-assessment skills in students so that they become more competent and confident to identify and self-correct weaknesses in their work. In this study, we trialled a feedback code as part of an integrated programme of formative and summative assessment tasks, which provided feedback to first-year students on their initial attempt at a scientific biology report. We investigated the students' perceptions of the feedback code and associated action plan exercise, and found that the code provided the majority of students with clear feedback, whilst the action plan provided a tool for decoding and interpreting the feedback and ensuring errors were not repeated in a subsequent report. We argue that a feedback code can be a valuable inclusion in a wider programme of feedback provision particularly when it is supported by activities that require students to engage with the codes and feed that learning forward to subsequent tasks.