This work presents an agent based system devoted to the simulation of passenger transportation scenarios. The architecture is build over a system, called MADARP, devoted to the implementation of concrete passenger transportation planning Systems. The transportation type considered by the system is the demand-responsive one, that is, a flexible approach in which trips requests are tacked online and scheduled over a set of available vehicles. The simulator allows diverse scenarios by varying the geographical network, the requests, and the set of vehicles. By managing diverse eventualities, it gives dynamicity to the simulation, such as, delays of vehicles, clients' no-show and vehicles' breakdowns, among others. The general design is depicted using the PASSI methodology, together with its implementation over the Jade agent platform.