Health advocacy remains one of the least explicitly assessed CanMEDS roles in Emergency Medicine. Objective structured clinical examination (OSCE) simulation is used to assess performance in real time but has not previously incorporated social determinants of health. We developed and piloted a simulation-based OSCE, embedding advocacy within acute clinical care and introduced novel assessment tools, completed by both examiners and standardized patients. Here we report the feasibility and acceptability of this OSCE and assessment tools. Twenty-two residents completed the advocacy and standard cases; 18 (82%) completed exit surveys. Most participants did not know advocacy would be assessed. Participants described the case as realistic and acceptable with minor suggestions for refinement. Assessors found the assessments intuitive to use and feasible to implement. This pilot suggests structured assessment of patient-level advocacy from both physician and patient perspectives can be feasibly integrated into simulation assessment without disrupting usual performance evaluation.