This article considers that reasoning over archives is a joint enterprise between archivists and researchers and that both groups are increasingly using machine agents to assist them in it. It starts by considering the processing of archivists, researchers and machine agents separately. Using the different perspectives this brings to highlight different aspects of that processing, as a process of sense-making, as scholarly research activity, as practices that realise and achieve data for the drawing of further inference, it reasserts the argument (...) that archives cannot be regarded as raw data to be reasoned over, but must be seen as the result of multiple representative and interpretive acts, of iterative realisation and activation as ‘data’ potentially involving many, many additional actors. It then goes on to consider how the involvement of machine agents fits into and potentially alters this picture by providing more detail about the basis on which they currently perform such acts. (shrink)