diff --git a/tests/ModelContextProtocol.AspNetCore.Tests/OAuth/AuthTests.cs b/tests/ModelContextProtocol.AspNetCore.Tests/OAuth/AuthTests.cs
index 265090e56..9099e2bfd 100644
--- a/tests/ModelContextProtocol.AspNetCore.Tests/OAuth/AuthTests.cs
+++ b/tests/ModelContextProtocol.AspNetCore.Tests/OAuth/AuthTests.cs
@@ -542,7 +542,7 @@ public async Task CannotAuthenticate_WhenProtectedResourceMetadataMissingResourc
 
                 var metadata = new ProtectedResourceMetadata
                 {
-                    AuthorizationServers = { new Uri(OAuthServerUrl) },
+                    AuthorizationServers = { OAuthServerUrl },
                     ScopesSupported = ["mcp:tools"],
                 };