Learner agency, often understood in terms of self-direction and negotiated engagement, is considered important in technical and vocational education and training (TVET). Yet nurturing and supporting agency is resource-intensive and difficult. In this paper, we consider learner agency for online TVET--a setting where content delivery models can be experienced as stultifying. We document the design and evaluation of specific task designs using the method and principle of double-stimulation, where prompts help participants to reconceptualise problematic situations and break out of conflicting motives. We draw on data from a research-intervention with adult learners undertaking a facilities management diploma online, while working. We explore how, across nine online workshops, task designs engendered transformative agency: the ability to collaboratively diverge from instructional intent, question dilemmatic conditions, and propose and enact change. We claim (1) that specific double-stimulation tasks encouraged participants to engage in understanding institutional practice, exposing conflict, and enacting change; (2) that participants came to view their own problematic conditions as stimuli for resistance, criticism, and development; and (3) that online resources were crucial for highlighting evidence of failure and learners' potential roles in change. Our findings are of importance to help learners set and evaluate their own learning agendas.