In this paper, we present LiteView, an experimental toolkit for end-user diagnosis of communication path problems in sensor network systems. This toolkit provides an on-site, interactive environment that helps answering questions related to the instantaneous communication environments. For example, it allows users to identify broken links or asymmetric links, which are likely to become traffic bottlenecks. It also allows users to identify traffic hotspots by collecting round-trip delays of arbitrary pairs of nodes. Compared to the previous work on sensor network troubleshooting, this toolkit has two key differences. First, its utilities are generic and applicationindependent, allowing users to easily transfer experiences in managing one deployment to another. Second, its utilities are interactive, allowing users to quickly obtain the current status, optimize the deployment decisions, and observe their immediate effects. The utilities provided in this paper are thus promising to identify and solve communication path problems.