Large Language Model–Based Chatbots and Agentic AI for Mental Health Counseling: Systematic Review of Methodologies, Evaluation Frameworks, and Ethical Safeguards

LLM-based MH counseling chatbots show promise for scalable and personalized support, but current evidence is limited by heterogeneous study designs, minimal external validation, and inconsistent reporting of safety and governance practices. Future work should prioritize clinically grounded evaluation frameworks, transparent reporting of model and prompt configurations, and stronger validation using standardized outcomes to support safe, reliable, and regulatory-ready deployment.