The technologies of visual representation are a great help for understanding items of information and the relations among them, especially, for non-expert users on Knowledge Based Systems, e.g. ontologies, which represent a world that can evolve and, therefore, has to be eventually refined. To ensure a cognitive communication soundness, we must integrate into solutions both, usability for these non-expert users and a logical accuracy on all involved elements. In this paper, the design principles for a tool for the visual repair of anomalies in consistent ontologies is presented. It helps users to obtain an ontological agreement between his mental model of the concepts into discourse domain and the intended model of the ontology (that is supposed to be consistent).