Some comments

Author: bgavrilMS

src/client/Microsoft.Identity.Client/AuthScheme/IAuthenticationOperation.cs

@@ -2,8 +2,6 @@
 // Licensed under the MIT License.
 
 using System.Collections.Generic;
-using System.Threading.Tasks;
-using Microsoft.Identity.Client.Cache.Items;
 
 namespace Microsoft.Identity.Client.AuthScheme
 {

src/client/Microsoft.Identity.Client/AuthScheme/PoP/MtlsPopAuthenticationOperation.cs

@@ -4,13 +4,15 @@
 using System.Collections.Generic;
 using System.Security.Cryptography;
 using System.Security.Cryptography.X509Certificates;
+using System.Threading;
+using System.Threading.Tasks;
 using Microsoft.Identity.Client.Internal;
 using Microsoft.Identity.Client.OAuth2;
 using Microsoft.Identity.Client.Utils;
 
 namespace Microsoft.Identity.Client.AuthScheme.PoP
 {
-    internal class MtlsPopAuthenticationOperation : IAuthenticationOperation
+    internal class MtlsPopAuthenticationOperation : IAuthenticationOperation2
     {
         private readonly X509Certificate2 _mtlsCert;
 
@@ -36,11 +38,6 @@ public IReadOnlyDictionary<string, string> GetTokenRequestParams()
             };
         }
 
-        public void FormatResult(AuthenticationResult authenticationResult)
-        {
-            //no-op
-        }
-
         private static string ComputeX5tS256KeyId(X509Certificate2 certificate)
         {
             // Extract the raw bytes of the certificate’s public key.
@@ -55,5 +52,15 @@ private static string ComputeX5tS256KeyId(X509Certificate2 certificate)
                 return Base64UrlHelpers.Encode(hash);
             }
         }
+
+        public Task FormatResultAsync(AuthenticationResult authenticationResult, CancellationToken cancellationToken = default)
+        {
+            return Task.CompletedTask;
+        }
+
+        public void FormatResult(AuthenticationResult authenticationResult)
+        {
+            // no-op
+        }
     }
 }

src/client/Microsoft.Identity.Client/AuthScheme/PoP/PopBrokerAuthenticationOperation.cs

@@ -5,6 +5,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Identity.Client.Cache.Items;
 using Microsoft.Identity.Client.Internal;
@@ -15,7 +16,7 @@ namespace Microsoft.Identity.Client.AuthScheme.PoP
     //Authentication Scheme used when MSAL Broker and pop are used together.
     //Tokens acquired from brokers will not be saved in the local ache and MSAL will not search the local cache during silent authentication.
     //This is because tokens are cached in the broker instead so MSAL will rely on the broker's cache for silent requests.
-    internal class PopBrokerAuthenticationOperation : IAuthenticationOperation
+    internal class PopBrokerAuthenticationOperation : IAuthenticationOperation2
     {
         public int TelemetryTokenType => TelemetryTokenTypeConstants.Pop;
 
@@ -25,9 +26,14 @@ internal class PopBrokerAuthenticationOperation : IAuthenticationOperation
 
         public string AccessTokenType => Constants.PoPTokenType;
 
+        public Task FormatResultAsync(AuthenticationResult authenticationResult, CancellationToken cancellationToken = default)
+        {
+            return Task.CompletedTask;
+        }
+
         public void FormatResult(AuthenticationResult authenticationResult)
         {
-            //no-op
+            // no-op
         }
 
         public IReadOnlyDictionary<string, string> GetTokenRequestParams()

src/client/Microsoft.Identity.Client/AuthScheme/SSHCertificates/SSHCertAuthenticationOperation.cs

@@ -3,13 +3,15 @@
 
 using System;
 using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
 using Microsoft.Identity.Client.Cache.Items;
 using Microsoft.Identity.Client.Internal;
 using Microsoft.Identity.Client.OAuth2;
 
 namespace Microsoft.Identity.Client.AuthScheme.SSHCertificates
 {
-    internal class SSHCertAuthenticationOperation : IAuthenticationOperation
+    internal class SSHCertAuthenticationOperation : IAuthenticationOperation2
     {
         internal const string SSHCertTokenType = "ssh-cert";
         private readonly string _jwk;
@@ -40,6 +42,11 @@ public SSHCertAuthenticationOperation(string keyId, string jwk)
 
         public string KeyId { get; }
 
+        public Task FormatResultAsync(AuthenticationResult authenticationResult, CancellationToken cancellationToken = default)
+        {
+            return Task.CompletedTask;
+        }
+
         public void FormatResult(AuthenticationResult authenticationResult)
         {
             // no-op

src/client/Microsoft.Identity.Client/Extensibility/ExternalBoundTokenScheme.cs

@@ -2,14 +2,16 @@
 // Licensed under the MIT License.
 
 using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
 using Microsoft.Identity.Client.AuthScheme;
 using Microsoft.Identity.Client.Cache.Items;
 using Microsoft.Identity.Client.Internal;
 using Microsoft.Identity.Client.Utils;
 
 namespace Microsoft.Identity.Client.Extensibility
 {
-    internal class ExternalBoundTokenScheme : IAuthenticationOperation
+    internal class ExternalBoundTokenScheme : IAuthenticationOperation2
     {
         private readonly string _keyId;
         private readonly string _tokenType;
@@ -28,6 +30,11 @@ public ExternalBoundTokenScheme(string keyId, string expectedTokenTypeFromEsts =
 
         public string AccessTokenType => _tokenType;
 
+        public Task FormatResultAsync(AuthenticationResult authenticationResult, CancellationToken cancellationToken = default)
+        {
+            return Task.CompletedTask;
+        }
+
         public void FormatResult(AuthenticationResult authenticationResult)
         {
             // no-op