Earth System analysis is the study of the joint dynamics of biogeophysical, social and technological processes on our planet. To advance our understanding of possible future development pathways and identify management options for navigating to safe operating spaces while avoiding undesirable domains, computer models of the Earth System are developed and applied. These models hardly represent dynamical properties of technological processes despite their great planetary-scale influence on the biogeophysical components of the Earth System and the associated risks for human societies posed, e.g. by climatic change or novel entities. In this contribution, we reflect on the technosphere from the perspective of Earth System analysis with a threefold focus on agency, networks and complex coevolutionary dynamics. First, we argue that Haff’s conception of the technosphere takes an extreme position in implying a strongly constrained human agency in the Earth System. Assuming that the technosphere develops according to dynamics largely independently of human intentions, Haff’s perspective appears incompatible with a humanistic view that underlies the sustainability discourse at large and, more specifically, current frameworks such as UN sustainable development goals and the safe and just operating space for humanity. Second, as an alternative to Haff’s static three-stratum picture, we propose complex adaptive networks as a concept for describing the interplay of social agents and technospheric entities and their emergent dynamics for Earth System analysis. Third, we argue that following a coevolutionary approach in conceptualising and modelling technospheric dynamics, also including the socio-cultural and biophysical spheres of the Earth System, could resolve the apparent conflict between the discourses on sustainability and the technosphere. Hence, this coevolutionary approach may point the way forward in modelling technological influences in the Earth System and may lead to a considerably deeper understanding of pathways to sustainable development in the future.