title: Identity Server 4 not return error description to controller
body: <p>I have an Identity server 4 project which follows the documentation on how to display the errors </p>
  
  <p><strong>Home Controller:</strong></p>
  
  <pre><code>public class HomeController : Controller
  {
      private readonly IIdentityServerInteractionService _interaction;
  
      public HomeController(IIdentityServerInteractionService interaction)
      {
          _interaction = interaction;
      }
  
      public IActionResult Index()
      {
          return View();
      }
  
      public async Task&lt;IActionResult&gt; Error(string errorId)
      {
          var vm = new ErrorViewModel();
          var message = await _interaction.GetErrorContextAsync(errorId);
          if (message != null)
              vm.Error = message;
          return View("Error", vm);
      }
  }
  </code></pre>
  
  <p>The Identity server itself is giving some good information in the logs</p>
  
  <pre><code>fail: IdentityServer4.Validation.AuthorizeRequestValidator[0]
        Unknown client or not enabled: 3CCF1B2D-D064-4A1B-BFD4-57E0451575C7.apps.biz
  {
          "SubjectId": "anonymous",
          "RequestedScopes": "",
          "Raw": {
            "client_id": "3CCF1B2D-D064-4A1B-BFD4-57E0451575C7.test.apps.biz",
            "redirect_uri": "http://localhost:4200/signin-oidc",
            "response_type": "id_token",
            "scope": "openid profile",
            "response_mode": "form_post",
            "nonce": "636589548258549622.YzMwMzRkNjAtYWU2Ni00ODlmLTg3ZWQtNmRmOThhYjcyN2JlZWFkYjk2MjEtNDAxNC00ZTQ1LWEzZTAtNTZmMWIyNDhkZjg1",
            "state": "CfDJ8FDPGFWZWNNOmnYDxcFlnVDZgaOG1kNakiXQF48y_4gnSxuIVAVQmMJ_4j9SUZz1TXGJDt4-8EKmoxLXuw3SZgyc5fy1ODzdS0Njd68T1W9dGxt8rFNrUF0njKk3XrSRTeJ45geS_uOL4w89OVupVq4UtHVbKxj3UMZLCn4W-BAXpXfo43KIT8RvxICMjbNtvPM1toEmMSlfdic6T6EZoxXpwim919xMLeQCY0S7QZdbc9DFfUfJkVYsLrofiBvQtZLfQjRQNp_7MiYFz_C4IQ7BAupErvZpcNvpBhQJWIt8BKlACVfKLHbvO6M0FKqa9A",
            "x-client-SKU": "ID_NET",
            "x-client-ver": "2.1.4.0"
          }
        }
  </code></pre>
  
  <p>and </p>
  
  <pre><code> fail: IdentityServer4.Validation.AuthorizeRequestValidator[0]
    Invalid redirect_uri: http://localhost:4200/signin-oidc
  {
          "ClientId": "testclient",
          "ClientName": "testclient",
          "AllowedRedirectUris": [
            "http://localhost:5002/signin-oidc"
          ],
          "SubjectId": "anonymous",
          "RequestedScopes": "",
          "Raw": {
            "client_id": "testclient",
            "redirect_uri": "http://localhost:4200/signin-oidc",
            "response_type": "code id_token",
            "scope": "openid profile",
            "response_mode": "form_post",
            "nonce": "636589567957415216.ZjYyZTU3MTEtZWRhZi00N2RhLWI1MjQtZThlZjk4NjY2NmJmZDQ4ZmUzNzQtMTI3MS00YTdiLTgzNDUtYThlMWU2NzcxMmM5",
            "state": "CfDJ8FDPGFWZWNNOmnYDxcFlnVByKSJA-wSjaBBIB2p-d1oUhuZNGBiD1gOFpnyxevmIKxNY1Hf15vlbpgLZoEVQ8O7UhyOpR1ANgUhhyl9nL4M63-2am7F1LJf9hwijkS0_WpxxJ-jYHlq4r99fS2tcaPFZjAG_UNjWYgTshD5Kps3czFvJOG04plaCn2zcKCX5AGgTVnxlG7__hi1ifn-xOipynq5nHBIasMT6doCmpjktAqx7AOK4C1D__YbVMkcRhC70qYFCfoSNhpUrROXZobP6GxYXd1y5EEbA_oXJjmePFdEL-MFQp0o5D_H_mXsU1g",
            "x-client-SKU": "ID_NET",
            "x-client-ver": "2.1.4.0"
          }
        }
  </code></pre>
  
  <p>However the only information isnt returned to my controller by <code>GetErrorContextAsync</code> so only the error name can be displayed to the user.</p>
  
  <p><a href="https://i.stack.imgur.com/LNijw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/LNijw.png" alt="enter image description here"></a></p>
  
  <p>The description of the error isn't filled out at all.   </p>
  
  <p>How do i get at the very least description populated?</p>
  
  <p>I am looking for a way of displaying some sensible information for the developers here.  However every error seams to return unauthorized_client so i cant tell the developer that its a problem with the redirect URI vs an invalid client id.</p>
  
  <pre><code>if (vm.Error.Error == "unauthorized_client") vm.Error.ErrorDescription = "Contact plugin developer.";
  </code></pre>
  
  <p>Note: Redirect URI one does appear to return a description.</p>