Worked on the spring-projects/spring-ai repository to enhance observability and stability by integrating cache metrics into the BedrockProxyChatModel’s TokenUsage object. Leveraged Java and AWS SDK to ensure cacheReadInputTokens and cacheWriteInputTokens were accurately tracked and exposed to observability handlers, improving metrics collection across backend systems. Addressed a bug where Bedrock cache metrics were not reported in the native Usage object, ensuring comprehensive monitoring. Improved metrics aggregation by merging cache metrics across multiple responses for precise per-request usage. The work also included code cleanup, such as removing redundant metadata and updating imports, contributing to a more maintainable and robust backend codebase.