anchor.diff:  `Accept` header.
   
   === Query parameters
  -No query parameter are required for the `/openapi` endpoint.  However, one
  +No query parameters are required for the `/openapi` endpoint.  However, one
   suggested but optional query parameter for vendors to support is `format`,
  -where the value can be `json`, to facilitate the toggle between the default `yaml`
  -format and `json` format.
  +where the value can be either `json` or `yaml`, to facilitate the toggle between
  +the default `yaml` format and `json` format.
   
   === Context root behaviour
   Vendors are required to ensure that the combination of each global https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.0.md#serverObject[server]
  
positive.code: === Static OpenAPI files
  
  Application developers may wish to include a pre-generated OpenAPI document that
  was written separately from the code (eg: with an editor such as https://editor.swagger.io/[this]).
  
  Depending on the scenario, the document may be fully complete or partially complete.
  If a document is fully complete then the application developer will want to set the
  `mp.openapi.scan.disable` configuration to `true`.  If a document is partially
  complete, then the application developer will need to augment the OpenAPI snippet
  with annotations, programming model, or via the filter.
  
  ==== Location and formats
  
  Vendors are required to fetch a single document with extension of `yml`, `yaml` or
  `json`, inside the application's `META-INF/openapi` folder.  If there are more than
  one document found that matched one of these extensions the behavior of which file
  is chosen is undefined (ie: each vendor may implement their own logic), which means
  that application developers should only place a single document into that folder.
  
  === Programming model
  
negative.code: 
  The https://github.com/eclipse/microprofile-open-api/blob/master/api/src/main/java/org/eclipse/microprofile/openapi/OASFactory.java[OASFactory] is used to create all of the elements of an OpenAPI tree.
  
  For example, the following snippet creates a simple https://github.com/eclipse/microprofile-open-api/blob/master/api/src/main/java/org/eclipse/microprofile/openapi/models/info/Info.java[Info] element that contains a title, description, and version.
  
  [source,java]
  ----
  