A keyword-driven developer is responsible for creating and managing a framework in automated testing where test scripts are written using data tables and keywords. They create keywords that represent a function or method to be performed on the application under test. These keywords serve as a simplified language for non-programmers to write test cases. The developer also ensures that the keyword-driven framework interacts properly with the application, troubleshooting any issues that arise. This approach enhances the reusability and maintainability of test cases, making it easier to manage and understand for both technical and non-technical users.