Set default ModelName as null.

src/Infrastructure/BotSharp.Abstraction/Conversations/IConversationStateService.cs

@@ -8,7 +8,7 @@ public interface IConversationStateService
     ConversationState Load(string conversationId);
     string GetState(string name, string defaultValue = "");
     ConversationState GetStates();
-    void SetState(string name, string value);
+    IConversationStateService SetState(string name, string value);
     void CleanState();
     void Save();
 }

src/Infrastructure/BotSharp.Abstraction/Conversations/Models/IncomingMessageModel.cs

@@ -12,7 +12,7 @@ public class IncomingMessageModel
     /// Model name
     /// </summary>
     [JsonPropertyName("model")]
-    public virtual string ModelName { get; set; } = "gpt-3.5-turbo";
+    public virtual string? ModelName { get; set; } = null;
 
     /// <summary>
     /// The sampling temperature to use that controls the apparent creativity of generated completions.

src/Infrastructure/BotSharp.Core/Agents/Services/AgentService.GetAgents.cs

@@ -1,6 +1,5 @@
 using BotSharp.Abstraction.Agents.Models;
 using BotSharp.Abstraction.Repositories;
-using System.IO;
 
 namespace BotSharp.Core.Agents.Services;
 
@@ -17,6 +16,7 @@ public partial class AgentService
         return query.ToList();
     }
 
+    [MemoryCache(10 * 60)]
     public async Task<Agent> GetAgent(string id)
     {
         var db = _services.GetRequiredService<IBotSharpRepository>();

src/Infrastructure/BotSharp.Core/Conversations/Services/ConversationStateService.cs

@@ -29,7 +29,7 @@ public class ConversationStateService : IConversationStateService, IDisposable
         _states = new ConversationState();
     }
 
-    public void SetState(string name, string value)
+    public IConversationStateService SetState(string name, string value)
     {
         var hooks = _services.GetServices<IConversationHook>();
         string preValue = _states.ContainsKey(name) ? _states[name] : "";
@@ -43,6 +43,8 @@ public class ConversationStateService : IConversationStateService, IDisposable
                 hook.OnStateChanged(name, preValue, currentValue).Wait();
             }
         }
+
+        return this;
     }
 
     public ConversationState Load(string conversationId)
@@ -118,6 +120,12 @@ public class ConversationStateService : IConversationStateService, IDisposable
         {
             _states[name] = defaultValue ?? "";
         }
+
+        if (_states[name] == null)
+        {
+            return defaultValue;
+        }
+
         return _states[name];
     }
 

src/Infrastructure/BotSharp.Core/Infrastructures/CompletionProvider.cs

@@ -4,13 +4,16 @@ namespace BotSharp.Core.Infrastructures;
 
 public class CompletionProvider
 {
-    public static IChatCompletion GetChatCompletion(IServiceProvider services)
+    public static IChatCompletion GetChatCompletion(IServiceProvider services, string? model = null)
     {
         var completions = services.GetServices<IChatCompletion>();
-        // var settings = services.GetRequiredService<ConversationSetting>();
-        // completions.FirstOrDefault(x => x.GetType().FullName.EndsWith(settings.ChatCompletion));
+
         var state = services.GetRequiredService<IConversationStateService>();
-        var model = state.GetState("model", "gpt-3.5-turbo");
+        if (model == null)
+        {
+            model = state.GetState("model", "gpt-3.5-turbo");
+        }
+        
         return completions.FirstOrDefault(x => x.ModelName == model);
     }
 }

src/Infrastructure/BotSharp.Core/Routing/Router.cs

@@ -1,4 +1,3 @@
-using Aspects.Cache;
 using BotSharp.Abstraction.Agents.Models;
 using BotSharp.Abstraction.Repositories;
 using BotSharp.Abstraction.Routing.Models;
@@ -53,11 +52,11 @@ public class Router : IAgentRouting
 
     public RoutingItem GetRecordByName(string name)
     {
-        return GetRoutingRecords().First(x => x.Name.ToLower() == name.ToLower());
+        return GetRoutingRecords().FirstOrDefault(x => x.Name.ToLower() == name.ToLower());
     }
 
     public RoutingItem GetRecordByAgentId(string id)
     {
-        return GetRoutingRecords().First(x => x.AgentId == id);
+        return GetRoutingRecords().FirstOrDefault(x => x.AgentId == id);
     }
 }

src/Infrastructure/BotSharp.Core/Routing/Simulator.cs

@@ -134,6 +134,11 @@ public class Simulator
 
     private void SaveStateByArgs(JsonDocument args)
     {
+        if (args == null)
+        {
+            return;
+        }
+
         var stateService = _services.GetRequiredService<IConversationStateService>();
         if (args.RootElement is JsonElement root)
         {

src/Infrastructure/BotSharp.OpenAPI/Controllers/ConversationController.cs

@@ -44,10 +44,10 @@ public class ConversationController : ControllerBase, IApiAdapter
     {
         var conv = _services.GetRequiredService<IConversationService>();
         conv.SetConversationId(conversationId, input.States);
-        conv.States.SetState("channel", input.Channel);
-        conv.States.SetState("model", input.ModelName);
-        conv.States.SetState("temperature", input.Temperature.ToString());
-        conv.States.SetState("sampling_factor", input.SamplingFactor.ToString());
+        conv.States.SetState("channel", input.Channel)
+            .SetState("model", input.ModelName)
+            .SetState("temperature", input.Temperature.ToString())
+            .SetState("sampling_factor", input.SamplingFactor.ToString());
 
         var response = new MessageResponseModel();
         var stackMsg = new List<RoleDialogModel>();

src/Plugins/BotSharp.Plugin.AzureOpenAI/Providers/ChatCompletionProvider.cs

@@ -20,9 +20,9 @@ namespace BotSharp.Plugin.AzureOpenAI.Providers;
 
 public class ChatCompletionProvider : IChatCompletion
 {
-    private readonly AzureOpenAiSettings _settings;
-    private readonly IServiceProvider _services;
-    private readonly ILogger _logger;
+    protected readonly AzureOpenAiSettings _settings;
+    protected readonly IServiceProvider _services;
+    protected readonly ILogger _logger;
 
     public virtual string ModelName => "gpt-3.5-turbo";
 

src/Plugins/BotSharp.Plugin.AzureOpenAI/Providers/GPT4CompletionProvider.cs

@@ -8,19 +8,12 @@ namespace BotSharp.Plugin.AzureOpenAI.Providers;
 
 public class GPT4CompletionProvider : ChatCompletionProvider
 {
-    private readonly AzureOpenAiSettings _settings;
-    private readonly IServiceProvider _services;
-    private readonly ILogger _logger;
-
     public override string ModelName => "gpt-4";
 
     public GPT4CompletionProvider(AzureOpenAiSettings settings, 
         ILogger<GPT4CompletionProvider> logger,
         IServiceProvider services) : base(settings, logger, services)
     {
-        _settings = settings;
-        _logger = logger;
-        _services = services;
     }
 
     protected override (OpenAIClient, string) GetClient()

src/Plugins/BotSharp.Plugin.ChatbotUI/ChatbotUiController.cs

@@ -78,8 +78,8 @@ public class ChatbotUiController : ControllerBase, IApiAdapter
         conv.SetConversationId(input.ConversationId, input.States);
         conv.States.SetState("model", input.ModelName);
         conv.States.SetState("channel", "webchat");
-        conv.States.SetState("temperature", "0.5");
-        conv.States.SetState("sampling_factor", "0.5");
+        conv.States.SetState("temperature", input.Temperature.ToString());
+        conv.States.SetState("sampling_factor", input.SamplingFactor.ToString());
 
         var result = await conv.SendMessage(input.AgentId, 
             message,