RFID tags can be used to add inexpensive, wireless, batteryless sensing to objects. However, quickly and accurately estimating the state of an RFID tag is difficult. In this work, we show how to achieve low-latency manipulation and movement sensing with off-the-shelf RFID tags and readers. Our approach couples a probabilistic filtering layer with a monte-carlo-sampling-based interaction layer, preserving uncertainty in tag reads until they can be resolved in the context of interactions. This allows designers’ code to reason about inputs at a high level. We demonstrate the effectiveness of our approach with a number of interactive objects, along with a library of components that can be combined to make new designs.