This case develops and applies an “Interdisciplinary Instructional Agent,” aiming to address complex issues teachers face in interdisciplinary instructional design, such as topic selection, activity design, and assessment. Developed on the Coze platform, this agent engages in multiple rounds of dialogue with users to generate comprehensive instructional plans, provide personalized suggestions, and offer subject-specific resources. The innovation lies in introducing generative AI into interdisciplinary thematic learning for junior high school students, assisting teachers in instructional design and implementation, and exploring its applications in education. This case provides a detailed introduction to the development process, functional positioning, and application effects of the agent, and demonstrates its value in enhancing teachers’ interdisciplinary abilities through practical teaching examples. This Interdisciplinary Instructional Agent holds promise for broader application in schools, contributing to the development of interdisciplinary education and promoting innovation in basic education.