title: Is it possible to consume the Search API using application token credentials?
body: <p>I need to do searches within SharePoint Online document libraries either using the new Search API (<a href="https://docs.microsoft.com/en-us/graph/search-concept-overview" rel="nofollow noreferrer">https://docs.microsoft.com/en-us/graph/search-concept-overview</a>) or using the <code>_api/search</code> endpoint.</p>
  <p>I've reached a dead end using the <code>_api/search</code> endpoint as it seem it doesn't accept application token credentials even with certificate authentication. It ends up giving a <code>{&quot;error_description&quot;:&quot;Unsupported security token.&quot;}</code></p>
  <p>So, maybe the new Search API can be used to search elements within SharePoint Online document libraries from an external service.</p>
  <p>However, the permission type <code>Application</code> is not supported as its said in the docs:</p>
  <p><a href="https://docs.microsoft.com/en-us/graph/api/search-query?view=graph-rest-beta&amp;tabs=http" rel="nofollow noreferrer">https://docs.microsoft.com/en-us/graph/api/search-query?view=graph-rest-beta&amp;tabs=http</a></p>
  <p>Any hints on this?</p>
  <p>Thank you very much</p>