Skeletal plans are a powerful way to reuse existing domain-specific procedural knowledge. In the Asgaard project, a set of tasks that support the design and the execution of skeletal plans by a human executing agent other than the original plan designer are designed. The underlying requirement to develop task-specific problem-solving methods is a modeling language. Therefore, within the Asgaard project, a time-oriented, intention-based language, called Asbru, was developed. During the design phase of plans, Asbru allows to express durative actions and plans caused by durative states of an observed agent. The intentions underlying these plans are represented explicitly as temporal patterns to be maintained, achieved or avoided. We will present the underlying idea of the Asgaard project and explain the time-oriented Asbru language. Finally, we show the benefits and limitations of the time-oriented, skeletal plan representation to be applicable in real-world, high-frequency domains.