A 32-year-old female nurse presents to the emergency department reporting acute onset auditory hallucinations commanding her to harm herself. She provides a detailed, dramatic history of childhood trauma and reports multiple previous psychiatric hospitalizations at out-of-state facilities that cannot be immediately verified. Mental status examination reveals the patient reporting vivid command auditory hallucinations, but her affect is calm and she makes good eye contact while describing these experiences. She provides textbook descriptions of hallucination characteristics without prompting and eagerly agrees to hospitalization. During the subsequent inpatient stay, nursing staff observe that her reported hallucinations occur exclusively during clinical interactions and are absent during unstructured ward time. She requests specific medications by name and becomes hostile when the treatment team suggests her symptoms may be improving. She has no identifiable external incentive such as disability claims, legal proceedings, or housing needs. Which diagnostic feature most reliably supports a diagnosis of factitious disorder imposed on self rather than genuine psychotic disorder?