This document provides the methodology proposed for specification of interfaces corresponding to WebServices offered by the Intelligent Core Adaptor. The goal of such a specification is to provide a formal description of offered services and to enumerate the services required from other ICAs. Common methodology will provide sound bases of co-operation between the different WP teams. The methodology enforces a step-wise iterative approach to co-operative design. At each step, a new version of the specification will be added until the expected services match the provided ones. Moreover, thanks to use of commonly understood process, it would be possible to generate automatically the WSDL description documents corresponding to the specified and agreed services.