This paper presents the jSynoPSys tool that implements the concept of Scenario-Based Testing from B machines. This consists in describing execution scenarios, expressed as regular expressions over the operations of the system, coupled with intermediate system states that have to be reached when the scenario is unfolded. The tool relies on the BZ-Testing-Tools engine, originally designed to perform symbolic animation and boundary test generation from B machines. The main advantage of our Scenario-Based Testing technique is that it performs a full abstraction of the operation parameter values, that are instantiated at the end, when the scenario has been completely unfolded, using constraint solving techniques.