China's National Standard for Arts Curriculum 2022 (CNSAC 2022) represents a transformative policy shift, mandating arts education as compulsory and elevating "creative practice" as one of four core competencies. This reform impacts 158 million students across 207,000 schools, making it one of the world's largest educational systems. However, translating abstract policy mandates into evaluable classroom outcomes remains a significant implementation challenge. Without structured evaluation mechanisms, policy aspirations risk remaining rhetoric rather than realized practice, particularly across China's geographically and economically diverse regions.This study aims to address the policy-to-practice implementation challenge by developing an Evaluation Index System of Musical Creativity (EISMC) that translates CNSAC 2022's "creative practice" competency into practice. Theoretically founded on the perspectives of Webster (thinking), William (personality), and Burnard (environment), EISMC is a tripartite evaluation system with three main dimensions: creative musical thinking, creative musical personality, and creative musical environment.The Delphi-AHP method was adopted in the consultations with strategic stakeholder, including policymakers (to ensure fidelity to reform goals), district officials (to bridge macro-policy with regional implementation), and educators (to ground indicators in classroom realities) (N=19, response rate 100%). Three iterative rounds of consultations established consensus on three primary indices, nine secondary indices, and 27 tertiary indicators (Kendall's W=0.20-0.28, p<0.001), of which AHP provided relative weighting to inform implementation priorities.The results reveal hierarchical implementation needs. Creative Musical Thinking dominates with a weighting of 0.643, validating CNSAC 2022's cognitive emphasis. Critically, Teacher Factors emerges as the fifth-highest weighted indicator (0.063) despite belonging to the Environmental dimension, identifying professional development as a scalable policy lever. The weighted structure provides education authorities with evidence-based benchmarks for resource allocation and cross-regional monitoring across diverse contexts.This study contributes to music education policy implementation on three aspects. For policymakers, EISMC demonstrates systematic operationalization of abstract competencies into frameworks of accountability, providing a transferable methodology to other arts domains and global reform efforts. For administrators, weighted indicators guide evidence-based resource allocation and professional development priorities. For practitioners, standardized criteria illuminate teaching expectations while maintaining creative autonomy. This policy-driven paradigm addresses a universal challenge: realizing curriculum visions in classrooms through mechanisms that reconcile standardization with adaptation to context.