<p>If you have a contact field, there should only be a valid
    email address inscribed.</p>
<h2>Noncompliant Code Example</h2>
<pre>
swagger: "2.0"
info:
  version: 1.0.0
  title: Swagger Petstore
  contact:
    email: randomString # Noncompliant: There should only be a valid email address in contact.
</pre>
<h2>Compliant Solution</h2>
<pre>
swagger: "2.0"
info:
  version: 1.0.0
  title: Swagger Petstore
  contact:
    email: max@mustermann.at
</pre>