This paper reports on the design and development of an end-of-unit assessment module for a self-access learning platform that is intended to help second and foreign language learners (L2) of English become (more) aware of pragmatic phenomena in the U.S. workplace. After providing a brief rationale, we first describe the computer-based, interactive pragmatics learning tool called Words at Work. Following the evidence-centered design (ECD) framework, we then outline the design of the prototype end-of-unit assessment module for Unit 3, a unit that deals with the speech act of request in general workplace communication. After presenting the proficiency model, the evidence model, and the task model, we provide in detail an overview of the task and item designs, including feedback implementation and ideas for scoring. We conclude the report with a discussion of the insights gained during the development process, as well as an outlook on future directions for research and development efforts.