This study explores teacher agency and strategies for extending teacher agency to meet the challenges brought about by the rapid Artificial Intelligence (AI) advancements. It adopts the concept of teacher agency, rather than teacher competency, to explore the complexities of teacher professional development. It builds upon the growing body of research that explores teacher agency through a systems approach, emphasizing the interdependent, interactive and evolving nature of teacher agency. Using the AI competency framework proposed by UNESCO as a foundation, this research investigates the current state of AI-empowered teaching practices in vocational colleges and schools in China. By analyzing empirical data from a survey, it provides insights into how teachers engage with AI technologies at different agency levels—ranging from basic adoption to pedagogical innovation and leadership in shaping AI-empowered education. The study underscores the importance of a human-centered mindset to AI in education, an approach which ensures that teachers retain agency while leveraging AI to innovate students' learning experience and teachers’ life-long professional development. Based on its findings, the study proposes strategies for expanding teacher agency at various stages of growth. These include equipping educators with AI knowledge and application skills, fostering awareness of the ethical and sociocultural implications of AI, deepening pedagogical strategies for meaningful AI integration, and promoting continuous professional development through AI-powered tools.