[BUG] Unable to retrieve / deserialize the annotations (URL citations) using Agent

[ZubaeyrMSFT]

Library name and version

Azure.AI.Projects 1.0.0-beta.3

Describe the bug

I am using Agents with Azure AI Search as knowledge. The response message from the agent contains the citation strings (ex: [51:0+source]), but the corresponding annotations doesn't include the actual reference links. It just contains the Text field with same value.

The type of the Annotation is: Azure.AI.Projects.UnknownMessageTextAnnotation and I am not able to cast it to MessageTextFileCitationAnnotation either.

  foreach (MessageContent contentItem in threadMessage.ContentItems)
  {
      if (contentItem is MessageTextContent textItem)
      {
          var textContent = (MessageTextContent)contentItem;
          messageContentBuilder.Append(textContent.Text);
          textContent.Annotations?.ForEach(annotation => 
          {
           _logger.LogInformation(JsonConvert.SerializeObject(annotation, settings: new JsonSerializerSettings { }));
          });
      }
  }

Expected behavior

Expecting the Annotations to contain the referenced URLs, and it should be able to cast to correct class.

Actual behavior

not able to get url citations from Annotations

Reproduction Steps

Please see bug description

Environment

No response

[github-actions]

Thanks for the feedback! We are routing this to the appropriate team for follow-up. cc @dargilco @jhakulin @nick863.