Multi-agent approach
Online - check their neighborhood (given by linkage topology) looking for new documents relevant to the user’s query
Intelligent - reason about decisions (where to go) to mimic browsing behavior of human user
Autonomous - make automatic decisions on behalf of the user, without need of user interaction
Adaptive - can adapt their strategies by evolution and reinforcement learning based on local features (words)
Distributed - have limited interaction w/other agents and w/client machine (amenable to mobile implementation)