.NET: Delete AgentResponse.{Try}Deserialize<T> methods (#3518)

* delete deserialize method of agent response

* order usings

* Update dotnet/samples/GettingStarted/FoundryAgents/FoundryAgents_Step05_StructuredOutput/Program.cs

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Update dotnet/samples/GettingStarted/Workflows/_Foundational/08_WriterCriticWorkflow/Program.cs

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Update dotnet/samples/GettingStarted/AGUI/Step05_StateManagement/Server/SharedStateAgent.cs

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Update dotnet/samples/AGUIClientServer/AGUIDojoServer/SharedState/SharedStateAgent.cs

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Update dotnet/samples/M365Agent/Agents/WeatherForecastAgent.cs

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

dotnet/samples/GettingStarted/AGUI/Step05_StateManagement/Server/SharedStateAgent.cs

@@ -107,7 +107,7 @@ internal sealed class SharedStateAgent : DelegatingAIAgent
         var response = allUpdates.ToAgentResponse();
 
         // Try to deserialize the structured state response
-        if (response.TryDeserialize(this._jsonSerializerOptions, out JsonElement stateSnapshot))
+        if (TryDeserialize(response.Text, this._jsonSerializerOptions, out JsonElement stateSnapshot))
         {
             // Serialize and emit as STATE_SNAPSHOT via DataContent
             byte[] stateBytes = JsonSerializer.SerializeToUtf8Bytes(
@@ -134,4 +134,25 @@ internal sealed class SharedStateAgent : DelegatingAIAgent
             yield return update;
         }
     }
+
+    private static bool TryDeserialize<T>(string json, JsonSerializerOptions jsonSerializerOptions, out T structuredOutput)
+    {
+        try
+        {
+            T? deserialized = JsonSerializer.Deserialize<T>(json, jsonSerializerOptions);
+            if (deserialized is null)
+            {
+                structuredOutput = default!;
+                return false;
+            }
+
+            structuredOutput = deserialized;
+            return true;
+        }
+        catch
+        {
+            structuredOutput = default!;
+            return false;
+        }
+    }
 }

dotnet/samples/GettingStarted/Agents/Agent_Step05_StructuredOutput/Program.cs

@@ -44,7 +44,7 @@ var updates = agentWithPersonInfo.RunStreamingAsync("Please provide information
 
 // Assemble all the parts of the streamed output, since we can only deserialize once we have the full json,
 // then deserialize the response into the PersonInfo class.
-PersonInfo personInfo = (await updates.ToAgentResponseAsync()).Deserialize<PersonInfo>(JsonSerializerOptions.Web);
+PersonInfo personInfo = JsonSerializer.Deserialize<PersonInfo>((await updates.ToAgentResponseAsync()).Text, JsonSerializerOptions.Web)!;
 
 Console.WriteLine("Assistant Output:");
 Console.WriteLine($"Name: {personInfo.Name}");

dotnet/samples/GettingStarted/FoundryAgents/FoundryAgents_Step05_StructuredOutput/Program.cs

@@ -61,7 +61,8 @@ IAsyncEnumerable<AgentResponseUpdate> updates = agentWithPersonInfo.RunStreaming
 
 // Assemble all the parts of the streamed output, since we can only deserialize once we have the full json,
 // then deserialize the response into the PersonInfo class.
-PersonInfo personInfo = (await updates.ToAgentResponseAsync()).Deserialize<PersonInfo>(JsonSerializerOptions.Web);
+PersonInfo personInfo = JsonSerializer.Deserialize<PersonInfo>((await updates.ToAgentResponseAsync()).Text, JsonSerializerOptions.Web)
+    ?? throw new InvalidOperationException("Failed to deserialize the streamed response into PersonInfo.");
 
 Console.WriteLine("Assistant Output:");
 Console.WriteLine($"Name: {personInfo.Name}");

dotnet/samples/GettingStarted/Workflows/_Foundational/08_WriterCriticWorkflow/Program.cs

@@ -327,7 +327,8 @@ internal sealed class CriticExecutor : Executor<ChatMessage, CriticDecision>
 
         // Convert the stream to a response and deserialize the structured output
         AgentResponse response = await updates.ToAgentResponseAsync(cancellationToken);
-        CriticDecision decision = response.Deserialize<CriticDecision>(JsonSerializerOptions.Web);
+        CriticDecision decision = JsonSerializer.Deserialize<CriticDecision>(response.Text, JsonSerializerOptions.Web)
+            ?? throw new JsonException("Failed to deserialize CriticDecision from response text.");
 
         Console.WriteLine($"Decision: {(decision.Approved ? "✅ APPROVED" : "❌ NEEDS REVISION")}");
         if (!string.IsNullOrEmpty(decision.Feedback))