Agent-based modeling has been of interest to researchers for some time now. Some research has focused on the analysis and design of such software, but none has truly addressed the need for automated assistance in creating agent-based simulators from initial problem comprehension. This paper proposes an approach addressing the gap and supporting the spiral process of generating an agent-based simulator. In particular, this approach enables the incremental and iterative representation of a problem and its translation into an executable model. Initially using an unconstrained ontology, the designer draws conceptual graphs representing the problem. Progressively, graph elements are linked hierarchically under concepts that are part of a predefined generic Scenarization Vocabulary (i.e., agent, patient, behaviour, attribute, parameter, variable �). This Scenarization semantic defines roles in the simulation. This approach is part of a broader research effort known as IMAGE that develops a toolset concept supporting collaborative understanding of complex situations.