Predictably achieving requirements validity has proven extremely difficult because of the informal nature of this property, and poor communication of application domain knowledge is implicated as a main barrier to increasing this validity. In related work, we developed a methodology that exploits cognitive psychology research to improve this communication. In this work, we describe support for the methodology via a toolset that directs involved parties in the construction of artifacts defined by the methodology; these artifacts by their structure and content enable the spread of application domain knowledge among developers and throughout the lifecycle. The toolset in addition supports documentation, various forms of analysis, and integration with other lifecycle artifacts. We used these tools in collaboration with an industry partner to develop experimental documentation for recording and dissemination of domain knowledge relevant to the design of a medical device, and we here describe this experience.