Component-based programming aims at producing higher quality software, increasing the reuse of components and permitting late composition. In the context of component-based programming, applications are treated as composition of components. Given an application composition, some of the components might have been developed outside the context of the application or its domain. As a result, the overall efficiency of the composition, in terms of cost and performance, becomes non-deterministic - may not be guaranteed to be efficient enough, even if the individual components have been proven to be efficient. In other words, two primary goals of software practice, efficiency and quality, do conflict with each other. In this paper, we argue that, this problem can partly be overcome by paying more attention to component-specific information, component metadata, during composition. We describe a possible means of extracting and organising the metadata and formats for specifying the metadata. Our scheme is independent of component- and programming-models and extensible. We see our work as a precursor to a possible runtime scheme, where we intend to facilitate extraction, maintenance and usage of component metadata at runtime.