1. A type checking method comprising: analyzing, using logic executed by a processor, a test script statement stored in a non-transitory memory coupled to the processor to determine: an exposed method expressed in the test script statement; Application Programming Interface (API) calls, executable by the processor, characterized by API call types that navigate in sequence to the exposed method; a destination Graphical User Interface (GUI) object that exposes the exposed method; finding, using the logic executed by the processor, an element path between sequential GUI objects in a GUI tree, where the element path leads to the destination GUI object, where the sequential GUI objects are characterized by GUI object types; determining, using the logic executed by the processor, whether the API call types in sequence are compatible with the GUI object types in sequence; obtaining, from a GUI object repository, validated action result for actions performed by the API calls on GUI object types in sequence; assigning API call types to each API call according to the action results that specify valid API calls useable to perform actions on particular GUI object types; obtaining, from the GUI object repository, mappings of GUI object types, where each of the mappings comprise properties of a GUI object type; assigning GUI object types to each GUI object according to the API call types in sequence determined to be compatible with the GUI object types in sequence; determining a GUI object interactions count for the sequential GUI objects based on a configurable number of GUI object interactions for the sequential GUI objects; and generating a type inferencer message guide that explain how to transform data during data exchange between the GUI object.