Anticipated advances in the use and capability of unmanned systems may increase the complexity in mission planning and human-machine teaming, creating challenges for mission performance, safety, and predictability. Verification and validation tools, such as model checking, have been applied to mission planning and is a promising approach but require expertise to use. This article describes the study of one such tool, with an interface that provides the human operator away to communicate their high-level mission goals and objectives to the model checking software without having to learn temporal logics or syntax. We describe the development and refinement of a prototype, as well as an experiment testing if a verification and validation tool can improve mission planning compared to a baseline without a verification and validation tool. Results showed that a tool increased mission planning accuracy, while also increasing mission planning time. Also, subjective workload was not different between the two configurations (tool & baseline). These results indicated that verification and validation tools with a suitable interface can enable humans to communicate mission objectives and constraints to machines, improving performance, safety, and predictability. Results also suggested that additional research to improve this communication would further increase the benefits and impact of these kinds of tools.