There are many specifications used to describe a Web API. One of the most popular ones is OpenAPI. This specification allows one to describe all the resources that can be accessed and manipulated through a REST Web API. An OpenAPI specification can be used to perform different kinds of analysis and verification of the service implementing the described API. A common challenge faced by researchers, however, is the lack of a standard repository of samples. A repository with annotated samples (e.g., antipatterns found in each specification) would be a valuable resource because it would help researchers and practitioners to verify new tools and techniques aiming at OpenAPI specifications. Such a repository would also allow direct comparison between different studies that decide to employ it. This paper describes the creation of a repository of annotated synthetic (but realistic) OpenAPI samples.