Penetration of distributed generation brings the advantages of on-site generation into the operation of distribution systems but makes the structure of power systems complex. Such a situation calls for the conversion of traditional power grid to a modern grid called smart grid. It improves the efficiency, reliability and quality of the services provided by the utilities due to the extensive communication, sensing and intelligence associated and embedded within smart grid. Smart distribution system is a vital part of smart grids which comprises of distributed generation, data communication medium to supervise and control the system performance. The data communication also facilitates the data exchange between the end-users and the utility. In such distribution systems, occurrence of a fault is more common due to the complexity involved and hence reliability is one of the most important factors to be taken care of. In this paper, an agent based intelligent restoration system is proposed and applied to a modified IEEE 123 node distribution system simulated using Open Distribution System Simulator (Open DSS). The novelty of the proposed agent system involves minimizing the network losses while restoring the service to the loads as per their priority without violating the network constraints. The results obtained proved that agent based restoration frameworks are successful in solving complicated multi objective and multi constraints problems effectively in distributed fashion.