title: How to use Secure String Parameters in Logic Apps
body: <p>I don't understand the purpose of the greyed out Actual Value field in the Logic Apps Designer. I guess it might be relevant when dealing with a Secure String, especially since this message comes up when entering a value in Default Value for this type of Parameter:</p>
  <blockquote>
  <p>It is not recommended to set a default value for type 'SecureString'
  because it will be stored as plain text.</p>
  </blockquote>
  <p><a href="https://i.stack.imgur.com/G7pTL.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/G7pTL.png" alt="Secure String Parameter in Designer mode" /></a></p>
  <p>I imagine there might be a way to pass the actual ApiKey value via a different mechanism at runtime, which would supersede my default string &quot;secret&quot;, but I have no idea how to do this. For instance, if my Logic App is on an HTTP Trigger, would passing a header? or query param? called &quot;ApiKey&quot; with the actual key work?</p>
  <p>Where is this process documented for all Trigger types?</p>
  <p>And still, what is the purpose of the Actual Value field in Designer?</p>
  <p><strong>Edit following @hury-shen's comment dated 2020-10-29 below:</strong></p>
  <p>This is what I've tried:</p>
  <p><a href="https://i.stack.imgur.com/mOpo3.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/mOpo3.png" alt="Logic App Code view" /></a></p>
  <p>however this (still) returns:</p>
  <blockquote>
  <p>Operation failed: The request content is not valid and could not be
  deserialized: 'Could not find member 'reference' on object of type
  'FlowTemplateParameter'. Path
  'properties.parameters.ApiKey.reference', line 1, position 3710.'.</p>
  </blockquote>
  <p>when I try to switch back to Designer mode.</p>