The openapi specification returned from OSUS can pass lint check [1]. There is another one (less popular tho) [2]. 

Definition of Done:

• The last cmd runs successfully.

  $ curl -s -o /tmp/output.json "https://api.stage.openshift.com/api/upgrades_info/openapi"
  $ lint-openapi /tmp/output.json

• A presubmit exists to avoid regression.

[1]. https://github.com/IBM/openapi-validator

[2]. https://github.com/python-openapi/openapi-spec-validator