  A longstanding challenge in mental well-being support is the reluctance of
people to adopt psychologically beneficial activities, often due to lack of
motivation, low perceived trustworthiness, and limited personalization of
recommendations. Chatbots have shown promise in promoting positive mental
health practices, yet their rigid interaction flows and less human-like
conversational experiences present significant limitations. In this work, we
explore whether the anthropomorphic design (both LLM's persona design and
conversational experience design) can enhance users' perception of the system
and their willingness to adopt mental well-being activity recommendations. To
this end, we introduce Sunnie, an anthropomorphic LLM-based conversational
agent designed to offer personalized well-being support through multi-turn
conversation and recommend practical actions grounded in positive psychology
and social psychology. An empirical user study comparing the user experience
with Sunnie and with a traditional survey-based activity recommendation system
suggests that the anthropomorphic characteristics of Sunnie significantly
enhance users' perception of the system and the overall usability;
nevertheless, users' willingness to adopt activity recommendations did not
change significantly.
