Predicate checking in conjunction with distributed systems can enable an investigating user to check predicates in the context of instance states and/or distributed states of a distributed system. In an example embodiment, a method entails accepting distributed system simulation data and performing a simulation of a distributed system using the distributed system simulation data to create distributed system simulated states. At least a portion of the distributed system simulated states are exposed. The exposed portion of the distributed system simulated states is retrieved and stored as exposed states for the distributed system. The exposed states for the distributed system are compared to predicate states for the distributed system. If an inconsistency is detected between the exposed states and the predicate states based on the comparing, at least one alarm is issued.