  Automatic Web service composition is a research direction aimed to improve
the process of aggregating multiple Web services to create some new, specific
functionality. The use of semantics is required as the proper semantic model
with annotation standards is enabling the automation of reasoning required to
solve non-trivial cases. Most previous models are limited in describing service
parameters as concepts of a simple hierarchy.
  Our proposed method is increasing the expressiveness at the parameter level,
using concept properties that define attributes expressed by name and type.
Concept properties are inherited. The paper also describes how parameters are
matched to create, in an automatic manner, valid compositions. Additionally,
the composition algorithm is practically used on descriptions of Web services
implemented by REST APIs expressed by OpenAPI specifications. Our proposal uses
knowledge models (ontologies) to enhance these OpenAPI constructs with JSON-LD
semantic annotations in order to obtain better compositions for involved
services. We also propose an adjusted composition algorithm that extends the
semantic knowledge defined by our model.
