In the Industry 4.0 era, with increased demands for customization, numerous companies struggle to accommodate changes in their businesses and to keep up with the pace of digital transformation. It follows that introducing new products or services based on an existing configuration or a new design is becoming more frequent. Managing the production ramp-up phase carefully is therefore emerging as one of the most critical steps in the product lifecycle. Although several general strategies and high-level frameworks are available in recent ramp-up management literature, data-backed tools and frameworks that deal with this question are scarce. This article aims to bridge this gap by developing a multi-agent system (MAS) supporting ramp-up management strategies assessment in multi-variant production contexts. An MAS relies on the concept of an agent, which is an autonomous entity operating in a society of agents in order to contribute to a general goal. This article studies the method used to develop an MAS and illustrates its applicability through a case study in the furniture sector. The article highlights the reusability and flexibility of the development method and the relevance of the MAS to decision-makers during ramp-up planning.