Learn to build a professional token tracking system for Large Language Models (LLMs) in this hands-on tutorial that demonstrates how to monitor and optimize AI request costs. Master token management by developing a Spring Boot application integrated with Spring AI, featuring automated usage logging through Spring AOP. Explore essential concepts including prompt tokens, generation tokens, and total usage tracking while implementing custom response objects for enhanced data handling. Discover the intricacies of token pricing structures, context window sizes, and best practices for production-level token monitoring. Gain practical experience creating a complete token tracking solution using Java and Spring Boot, with detailed guidance on REST API integration and automated logging implementation. Suitable for Java developers with basic knowledge of Spring Boot and REST APIs who want to effectively manage and optimize their AI implementation costs.