Ambient environments consist of components surrounding the user and offering services. Applications can here be composed opportunistically and automatically by an intelligent system that puts together available components. Thus, applications that are a priori unknown emerge from the environment. The problem is in the intelligible presentation to an average user of those emerging composite applications. Our approach consists in automatic generation of user-oriented application descriptions from unit descriptions of each component and service. For that, we propose a well-defined language for component description and a method for combining descriptions. A prototype has been developed and used to experiment the generation of different composite application descriptions. Based on these experiments, we assess the degree of fulfillment of the requirements we have identified for the problem.