Worked on improving reliability and developer experience in the google/adk-js repository by enhancing error handling within the Runner class. Focused on addressing edge cases where the appName was missing or sessions were invalid, implementing targeted TypeScript logic to provide clearer, more actionable error messages. Developed and integrated automated unit tests to validate these new error flows, ensuring that regressions would be caught early and that error handling remained robust. This work reduced misleading errors and support overhead, while also increasing developer productivity by making issues easier to diagnose and resolve. Emphasized error handling and unit testing throughout the development process.