In this paper, we will present a state of the art in using multi-agent technology for wireless sensor networks where the main goal is the conception of software architecture and the network organization dedicated to optimization, performance analysis, and monitoring. Then we explore in particular, the issues of topology control and works in this field and the use of multi-agent systems. Finally we will propose an agent based algorithm for fault tolerance and topology control in a wireless sensor network. Our proposal consists to embed an agent at each node that is responsible for selecting its parent node or the next hop to the sink when transferring packets. The process of parent change is based on the computation of a fault tolerance degree which is calculated periodically by the agent in cooperation with neighboring nodes, in addition to other parameters such as the number of hops, the energy and the quality of link. Simulation results show that this method of changing parent allows a fault tolerant network with enhanced life time compared with the collect tree protocol CTP used for data gathering in a wireless sensor network.