From Design Principles to Practice: Validation of a UX Design Checklist for Affective Conversational Agents in Mental Well-Being

University students' psychological well-being is a critical public health concern, creating demand for digital interventions that are both safe and effective. Although conversational agents offer scalable support, existing usability heuristics cannot address complex affective dimensions such as emotional containment and clinical safety, revealing a gap in specialized design frameworks. To address this, the study introduces the “Affective Design Checklist,” a practical inspection tool for developing and auditing mental health conversational agents. Using Jabareen's conceptual framework analysis with a PRISMA-guided systematic review of 43 key articles, the instrument underwent a two-stage validation by a panel of ten experts, achieving a scale-level Content Validity Index (S-CVI/Ave) of 0.971, with near-unanimous agreement on ethical and regulatory dimensions. This research translates abstract bioethical and affective computing principles into actionable verification items, offering a specialized standard to ensure digital interventions are technically usable, affectively competent, and ethically aligned with student needs.