What is the difference between biz_inbox and setup_tool as attribution attribute on the Facebook SDK for JavaScript code below?

  <!-- Your Chat Plugin code -->
  <div class="fb-customerchat"
    attribution="biz_inbox"
    page_id="{PAGE_ID}">
  </div>

  <!-- Your Chat Plugin code -->
  <div class="fb-customerchat"
    attribution="setup_tool"
    page_id="{PAGE_ID}">
  </div>