Conceptualization, operationalization, and measurement of machine companionship: a scoping review

Abstract The notion of machine companions has long been embedded in socio-technological imaginaries. Recent advances in AI have moved those media musings into believable sociality manifested in interfaces, robotic bodies, and devices. Those machines are often referred to colloquially as “companions,” yet there is little careful engagement of machine companionship (MC) as a formal concept or measured variable. This PRISMA-guided scoping review systematically samples, surveys, and synthesizes current scholarly works on MC (N = 71; 2017–2025). Works varied widely in considerations of MC according to guiding theories, dimensions of a priori specified properties (subjectively positive, sustained over time, co-active, autotelic), and in measured concepts (with more than 50 distinct measured variables). We ultimately offer a literature-guided definition of MC as an autotelic, coordinated connection between human and machine that unfolds over time and is subjectively positive; through a facet-theoretical lens, we suggest how this definition can scaffold future research.