Hari Gautam enhanced the Catalogi API within the valtimo-backend-libraries and valtimo repositories by developing a new plugin action to retrieve eigenschap URLs and store them as process variables, supporting both direct URL input and dynamic lookup by property name within a zaaktype. He strengthened backend reliability by introducing custom exception classes and standardizing error messages for not-found scenarios, improving error context and system observability. Using Java and Kotlin, Hari expanded unit test coverage to validate these enhancements, ensuring robust handling of edge cases. His work reduced manual troubleshooting and enabled smoother workflow automation through improved API integration and exception handling.