Worked on the langchain4j/langchain4j repository to deliver a System Message Metadata and Context Management feature, introducing a SystemMessage class for handling system-level messages within chat metadata. This addition improved context management during AI service invocations, enabling clearer instructions and enhancing the user experience. The implementation involved comprehensive unit testing in Java, covering both positive and negative scenarios across multiple modules to ensure reliability. Previous changes to system-message handling were reverted to maintain compatibility and prevent regressions. The work demonstrated strong attention to test coverage, code quality, and cross-module validation, focusing on robust software development and maintainable AI service integration.