title: Swagger throws "Swagger Error Not a valid parameter definition" for body parameter
body: <p>This is my input:</p>
  
  <pre><code>  parameters:
      - name: body
        in:  body
        required: true
        type: object
        description: | 
          The body.
        schema:
          $ref: '#/definitions/CsrRequest'
  </code></pre>
  
  <p>And it says this:</p>
  
  <p>Details</p>
  
  <pre><code> Object
  code:  "ONE_OF_MISSING"
  message:  "Not a valid parameter definition"
   path: Array [5]
   inner: Array [2]
  level: 900
  type:  "Swagger Error"
  description:  "Not a valid parameter definition"
  lineNumber: 24
  </code></pre>
  
  <p>What am I doing wrong?</p>