Where to put @OpenAPIDefinition?

The documentation for defining general API information using the quarkus-smallrye-openapi extension is extremely sparse, and does not explain how to use all the annotations for setting up the openApi generation.

For some background, I am using a clean and largely empty project (quarkus version1.0.1.FINAL) generated from code.quarkus.io, with a single class defined as followed (With the attempted @OpenAPIDefinition annotation):

@OpenAPIDefinition(
    info = @Info(
        title = "Custom API title",
        version = "3.14"
    )
)
@Path("/hello")
public class ExampleResource {

    @GET
    @Produces(MediaType.TEXT_PLAIN)
    public String hello() {
        return "hello";
    }
}

I have eventually found that general api information (contact info, version, etc) through much digging is defined using the @OpenAPIDefinition annotation, but when used on my existing endpoint definition, no changes are made to the generated openapi specification. What am I doing wrong?