Introduction: Conducting research on human-computer interaction and information retrieval requires unobtrusive observations within existing network architectures. State of the art: Most of the available tools are not suitable to be applied within restricted clinical systems. The specific requirements hinder analysis of the human factors in health sciences. Concept: We identified extensions for popular web browsers as a suitable way to conduct studies in highly regulated environments. Implementation: Considering the specialized requirements and an adequate level of transparency for the recorded clinician, we developed an open-source Web Extension compatible with major web browsers. Lessons learned: We identified the challenges associated with the specific tool and are preparing its use to understand clinical reasoning in personalized oncology.