Developed an internal regression testing API for PyMotorCAD RPC methods within the ansys/pymotorcad repository, focusing on enhancing the reliability of remote procedure call changes. The work involved creating the rpc_methods_testing.py module, which introduced the _RpcMethodsTesting class and a run_regression_tests method to automate internal regression test generation. By integrating this workflow with core RPC methods and updating codecov.yml to exclude the new testing file from coverage metrics, the solution preserved meaningful coverage data. Leveraging Python and expertise in API development and testing frameworks, this contribution established a foundation for automated regression testing and improved feedback cycles for RPC stability.