["European Journal of Education, Volume 61, Issue 2, June 2026. ", "\nABSTRACT\nThe rapid scaling of generative artificial intelligence (GenAI) technology presents opportunities for personalised learning experiences and facilitates collaborative learning, including collaborative argumentation (CA). However, empirical research examining students' perceptions of GenAI‐assisted CA within classroom contexts remains limited. This study explored university students' experiences with GenAI‐assisted CA through in‐depth interviews with 36 students following a CA activity using a ChatGPT4‐embedded argumentation platform developed by the research team. Findings indicate that students viewed GenAI as serving multiple roles, including tool, facilitator, teaching assistant and machine buddy. Students perceived that GenAI‐assisted CA could empower task performance and create a collaborative learning environment. Meanwhile, they found three challenges, including students'‐, AI‐ and learning environment‐related challenges during GenAI‐assisted CA. These findings offer evidence‐based strategies for educators seeking to integrate GenAI into the design of collaborative learning activities and guidelines for developers on the design of pedagogical AI for creating student‐centered GenAI‐powered collaborative learning.\n"]