diff --git a/Directory.Packages.props b/Directory.Packages.props
index c840c156..d5721a14 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -46,7 +46,7 @@
     <PackageVersion Include="Whisper.net.Runtime" Version="1.8.1" />
     <PackageVersion Include="NCrontab" Version="3.3.3" />
     <PackageVersion Include="Azure.AI.OpenAI" Version="2.2.0-beta.5" />
-    <PackageVersion Include="OpenAI" Version="2.2.0" />
+    <PackageVersion Include="OpenAI" Version="2.2.0-beta.4" />
     <PackageVersion Include="MailKit" Version="4.11.0" />
     <PackageVersion Include="Microsoft.Data.Sqlite" Version="8.0.8" />
     <PackageVersion Include="MySql.Data" Version="9.0.0" />
diff --git a/src/Infrastructure/BotSharp.Abstraction/Agents/Constants/LlmConstant.cs b/src/Infrastructure/BotSharp.Abstraction/Agents/Constants/LlmConstant.cs
index 3919ca57..e45c8b15 100644
--- a/src/Infrastructure/BotSharp.Abstraction/Agents/Constants/LlmConstant.cs
+++ b/src/Infrastructure/BotSharp.Abstraction/Agents/Constants/LlmConstant.cs
@@ -3,4 +3,5 @@ namespace BotSharp.Abstraction.Agents.Constants;
 public static class LlmConstant
 {
     public const int DEFAULT_MAX_OUTPUT_TOKEN = 1024;
+    public const string DEFAULT_REASONING_EFFORT_LEVEL = "low";
 }
diff --git a/src/Infrastructure/BotSharp.Abstraction/Agents/Models/AgentLlmConfig.cs b/src/Infrastructure/BotSharp.Abstraction/Agents/Models/AgentLlmConfig.cs
index f1df3a01..75e3aa93 100644
--- a/src/Infrastructure/BotSharp.Abstraction/Agents/Models/AgentLlmConfig.cs
+++ b/src/Infrastructure/BotSharp.Abstraction/Agents/Models/AgentLlmConfig.cs
@@ -34,4 +34,11 @@ public class AgentLlmConfig
     [JsonPropertyName("max_output_tokens")]
     [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
     public int? MaxOutputTokens { get; set; }
+
+    /// <summary>
+    /// Reasoning effort level
+    /// </summary>
+    [JsonPropertyName("reasoning_effort_level")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+    public string? ReasoningEffortLevel { get; set; }
 }
diff --git a/src/Infrastructure/BotSharp.OpenAPI/Controllers/AgentController.cs b/src/Infrastructure/BotSharp.OpenAPI/Controllers/AgentController.cs
index 4543fe19..b6950e04 100644
--- a/src/Infrastructure/BotSharp.OpenAPI/Controllers/AgentController.cs
+++ b/src/Infrastructure/BotSharp.OpenAPI/Controllers/AgentController.cs
@@ -14,8 +14,7 @@ public class AgentController : ControllerBase
     public AgentController(
         IAgentService agentService,
         IUserIdentity user,
-        IServiceProvider services  
-        )
+        IServiceProvider services)
     {
         _agentService = agentService;
         _user = user;
diff --git a/src/Plugins/BotSharp.Plugin.MongoStorage/Models/AgentLlmConfigMongoElement.cs b/src/Plugins/BotSharp.Plugin.MongoStorage/Models/AgentLlmConfigMongoElement.cs
index b626d7da..63bc3b20 100644
--- a/src/Plugins/BotSharp.Plugin.MongoStorage/Models/AgentLlmConfigMongoElement.cs
+++ b/src/Plugins/BotSharp.Plugin.MongoStorage/Models/AgentLlmConfigMongoElement.cs
@@ -10,6 +10,7 @@ public class AgentLlmConfigMongoElement
     public bool IsInherit { get; set; }
     public int MaxRecursionDepth { get; set; }
     public int? MaxOutputTokens { get; set; }
+    public string? ReasoningEffortLevel { get; set; }
 
     public static AgentLlmConfigMongoElement? ToMongoElement(AgentLlmConfig? config)
     {
@@ -22,6 +23,7 @@ public class AgentLlmConfigMongoElement
             IsInherit = config.IsInherit,
             MaxRecursionDepth = config.MaxRecursionDepth,
             MaxOutputTokens = config.MaxOutputTokens,
+            ReasoningEffortLevel = config.ReasoningEffortLevel
         };
     }
 
@@ -36,6 +38,7 @@ public class AgentLlmConfigMongoElement
             IsInherit = config.IsInherit,
             MaxRecursionDepth = config.MaxRecursionDepth,
             MaxOutputTokens = config.MaxOutputTokens,
+            ReasoningEffortLevel = config.ReasoningEffortLevel
         };
     }
 }
diff --git a/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Chat/ChatCompletionProvider.cs b/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Chat/ChatCompletionProvider.cs
index af7e7e0a..c9318d79 100644
--- a/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Chat/ChatCompletionProvider.cs
+++ b/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Chat/ChatCompletionProvider.cs
@@ -17,7 +17,12 @@ public class ChatCompletionProvider : IChatCompletion
 
     private readonly Dictionary<string, float> _defaultTemperature = new()
     {
-        { "o4-mini", 1.0f }
+        { "o3", 1.0f },
+        { "o3-mini", 1.0f },
+        { "o4-mini", 1.0f },
+        { "gpt-5", 1.0f },
+        { "gpt-5-mini", 1.0f },
+        { "gpt-5-nano", 1.0f }
     };
 
     public virtual string Provider => "openai";
@@ -499,13 +504,42 @@ public class ChatCompletionProvider : IChatCompletion
                         ? tokens
                         : agent.LlmConfig?.MaxOutputTokens ?? LlmConstant.DEFAULT_MAX_OUTPUT_TOKEN;
 
+        var level = state.GetState("reasoning_effort_level")
+                         .IfNullOrEmptyAs(agent?.LlmConfig?.ReasoningEffortLevel ?? string.Empty)
+                         .IfNullOrEmptyAs(LlmConstant.DEFAULT_REASONING_EFFORT_LEVEL);
+        var reasoningEffortLevel = ParseReasoningEffortLevel(level);
+
         return new ChatCompletionOptions()
         {
             Temperature = temperature,
-            MaxOutputTokenCount = maxTokens
+            MaxOutputTokenCount = maxTokens,
+            ReasoningEffortLevel = reasoningEffortLevel
         };
     }
 
+    private ChatReasoningEffortLevel? ParseReasoningEffortLevel(string? level)
+    {
+        if (string.IsNullOrWhiteSpace(level) || !_defaultTemperature.ContainsKey(_model))
+        {
+            return null;
+        }
+
+        var effortLevel = ChatReasoningEffortLevel.Low;
+        switch (level.ToLower())
+        {
+            case "medium":
+                effortLevel = ChatReasoningEffortLevel.Medium;
+                break;
+            case "high":
+                effortLevel = ChatReasoningEffortLevel.High;
+                break;
+            default:
+                break;
+        }
+
+        return effortLevel;
+    }
+
     public void SetModelName(string model)
     {
         _model = model;