Fault tolerance and scalability are two fundamental is- sue of discovery information protocols for wide area dis- tributed systems. In a our previous work we have intro- duced a discovery protocol focused on these two require- ments but, although the led tests have shown the validity of adopted solution, the protocol performance are bound by the slow update mechanism of service cache, one of funda- mental component of discovery algorithm. In particular, a slow update forces a long start-up time. In this paper we proposed a different update cache tech- nique, based on mobile agents technology, no more focused on analysis of message forwarded through the network (pas- sive update), but on autonomous research of information held in the other peers (active update). This strategy allows to rise in a fast manner the informative content of service cache improving the discovery algorithm performance.