A tool shelf for tracking design decisions

An extensible conceptual model for recording design decisions and other supporting information is described along with the tool shell OSC in which it is embedded. The OSC shell consists of a design database and a family of query, manipulation, and extension facilities. The design database maintains a record of the design process. The extension facilities can be used to enrich the design database scheme incrementally and create new query or manipulation facilities. The core model provides a base language for describing the design process. Extension facilities augment this basis with more powerful, customized facilities. The implementation of the OSC shell using ESSAIM, an expert-system shell based on Smalltalk, is discussed.<>