diff --git a/src/Infrastructure/BotSharp.Abstraction/Files/IFileStorageService.cs b/src/Infrastructure/BotSharp.Abstraction/Files/IFileStorageService.cs
index 8e255e76..ef40e11c 100644
--- a/src/Infrastructure/BotSharp.Abstraction/Files/IFileStorageService.cs
+++ b/src/Infrastructure/BotSharp.Abstraction/Files/IFileStorageService.cs
@@ -7,9 +7,9 @@ public interface IFileStorageService
     #region Common
     string GetDirectory(string conversationId);
     IEnumerable<string> GetFiles(string relativePath, string? searchQuery = null);
-    byte[] GetFileBytes(string fileStorageUrl);
+    BinaryData GetFileBytes(string fileStorageUrl);
     bool SaveFileStreamToPath(string filePath, Stream stream);
-    bool SaveFileBytesToPath(string filePath, byte[] bytes);
+    bool SaveFileBytesToPath(string filePath, BinaryData binary);
     string GetParentDir(string dir, int level = 1);
     bool ExistDirectory(string? dir);
     void CreateDirectory(string dir);
diff --git a/src/Infrastructure/BotSharp.Abstraction/Files/Models/InstructFileModel.cs b/src/Infrastructure/BotSharp.Abstraction/Files/Models/InstructFileModel.cs
index 7eaddd5a..e7372416 100644
--- a/src/Infrastructure/BotSharp.Abstraction/Files/Models/InstructFileModel.cs
+++ b/src/Infrastructure/BotSharp.Abstraction/Files/Models/InstructFileModel.cs
@@ -10,9 +10,16 @@ public class InstructFileModel : FileBase
     public string? FileExtension { get; set; } = string.Empty;
 
     /// <summary>
-    /// External file url
+    /// File url
     /// </summary>
     [JsonPropertyName("file_url")]
     [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
     public string? FileUrl { get; set; } = string.Empty;
+
+    /// <summary>
+    /// File MIME type
+    /// </summary>
+    [JsonPropertyName("content_type")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+    public string? ContentType { get; set; }
 }
diff --git a/src/Infrastructure/BotSharp.Abstraction/Files/Utilities/FileUtility.cs b/src/Infrastructure/BotSharp.Abstraction/Files/Utilities/FileUtility.cs
index db9ccb65..d7867cf6 100644
--- a/src/Infrastructure/BotSharp.Abstraction/Files/Utilities/FileUtility.cs
+++ b/src/Infrastructure/BotSharp.Abstraction/Files/Utilities/FileUtility.cs
@@ -11,11 +11,16 @@ public static class FileUtility
     /// </summary>
     /// <param name="data"></param>
     /// <returns></returns>
-    public static (string, byte[]) GetFileInfoFromData(string data)
+    public static (string?, BinaryData) GetFileInfoFromData(string data)
     {
         if (string.IsNullOrEmpty(data))
         {
-            return (string.Empty, new byte[0]);
+            return (null, BinaryData.Empty);
+        }
+
+        if (!data.StartsWith("data:"))
+        {
+            return (null, BinaryData.FromString(data));
         }
 
         var typeStartIdx = data.IndexOf(':');
@@ -25,13 +30,13 @@ public static class FileUtility
         var base64startIdx = data.IndexOf(',');
         var base64Str = data.Substring(base64startIdx + 1);
 
-        return (contentType, Convert.FromBase64String(base64Str));
+        return (contentType, BinaryData.FromString(base64Str));
     }
 
-    public static string BuildFileDataFromFile(string fileName, byte[] bytes)
+    public static string BuildFileDataFromFile(string fileName, BinaryData binary)
     {
         var contentType = GetFileContentType(fileName);
-        var base64 = Convert.ToBase64String(bytes);
+        var base64 = Convert.ToBase64String(binary.ToArray());
         return $"data:{contentType};base64,{base64}";
     }
 
diff --git a/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Audio.cs b/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Audio.cs
index d61b6165..130baa19 100644
--- a/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Audio.cs
+++ b/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Audio.cs
@@ -14,9 +14,8 @@ public partial class FileInstructService
         }
 
         var completion = CompletionProvider.GetAudioTranscriber(_services, provider: options?.Provider, model: options?.Model);
-        var audioBytes = await DownloadFile(audio);
-        using var stream = new MemoryStream();
-        stream.Write(audioBytes, 0, audioBytes.Length);
+        var audioBinary = await DownloadFile(audio);
+        using var stream = audioBinary.ToStream();
         stream.Position = 0;
 
         var fileName = $"{audio.FileName ?? "audio"}.{audio.FileExtension ?? "wav"}";
diff --git a/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Image.cs b/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Image.cs
index dd2e02d4..68b24f32 100644
--- a/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Image.cs
+++ b/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Image.cs
@@ -1,7 +1,5 @@
 using BotSharp.Abstraction.Instructs.Models;
 using BotSharp.Abstraction.Instructs;
-using System.IO;
-using BotSharp.Abstraction.Infrastructures;
 
 namespace BotSharp.Core.Files.Services;
 
@@ -21,7 +19,12 @@ public partial class FileInstructService
         {
             new RoleDialogModel(AgentRole.User, text)
             {
-                Files = images?.Select(x => new BotSharpFile { FileUrl = x.FileUrl, FileData = x.FileData }).ToList() ?? []
+                Files = images?.Select(x => new BotSharpFile
+                {
+                    FileUrl = x.FileUrl,
+                    FileData = x.FileData,
+                    ContentType = x.ContentType
+                }).ToList() ?? []
             }
         });
 
@@ -76,9 +79,8 @@ public partial class FileInstructService
 
         var innerAgentId = options?.AgentId ?? Guid.Empty.ToString();
         var completion = CompletionProvider.GetImageCompletion(_services, provider: options?.Provider ?? "openai", model: options?.Model ?? "dall-e-2");
-        var bytes = await DownloadFile(image);
-        using var stream = new MemoryStream();
-        stream.Write(bytes, 0, bytes.Length);
+        var binary = await DownloadFile(image);
+        using var stream = binary.ToStream();
         stream.Position = 0;
 
         var fileName = $"{image.FileName ?? "image"}.{image.FileExtension ?? "png"}";
@@ -113,9 +115,8 @@ public partial class FileInstructService
         var instruction = await GetAgentTemplate(innerAgentId, options?.TemplateName);
 
         var completion = CompletionProvider.GetImageCompletion(_services, provider: options?.Provider ?? "openai", model: options?.Model ?? "dall-e-2");
-        var bytes = await DownloadFile(image);
-        using var stream = new MemoryStream();
-        stream.Write(bytes, 0, bytes.Length);
+        var binary = await DownloadFile(image);
+        using var stream = binary.ToStream();
         stream.Position = 0;
 
         var fileName = $"{image.FileName ?? "image"}.{image.FileExtension ?? "png"}";
@@ -153,15 +154,13 @@ public partial class FileInstructService
         var instruction = await GetAgentTemplate(innerAgentId, options?.TemplateName);
 
         var completion = CompletionProvider.GetImageCompletion(_services, provider: options?.Provider ?? "openai", model: options?.Model ?? "dall-e-2");
-        var imageBytes = await DownloadFile(image);
-        var maskBytes = await DownloadFile(mask);
+        var imageBinary = await DownloadFile(image);
+        var maskBinary = await DownloadFile(mask);
 
-        using var imageStream = new MemoryStream();
-        imageStream.Write(imageBytes, 0, imageBytes.Length);
+        using var imageStream = imageBinary.ToStream();
         imageStream.Position = 0;
 
-        using var maskStream = new MemoryStream();
-        maskStream.Write(maskBytes, 0, maskBytes.Length);
+        using var maskStream = maskBinary.ToStream();
         maskStream.Position = 0;
 
         var imageName = $"{image.FileName ?? "image"}.{image.FileExtension ?? "png"}";
diff --git a/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Pdf.cs b/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Pdf.cs
index b593e949..5e89f428 100644
--- a/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Pdf.cs
+++ b/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.Pdf.cs
@@ -22,7 +22,7 @@ public partial class FileInstructService
         try
         {
             var provider = options?.Provider ?? "openai";
-            var pdfFiles = await DownloadFiles(sessionDir, files);
+            var pdfFiles = await DownloadAndSaveFiles(sessionDir, files);
 
             var targetFiles = pdfFiles;
             if (provider != "google-ai")
@@ -78,7 +78,7 @@ public partial class FileInstructService
     }
 
     #region Private methods
-    private async Task<IEnumerable<string>> DownloadFiles(string dir, List<InstructFileModel> files, string extension = "pdf")
+    private async Task<IEnumerable<string>> DownloadAndSaveFiles(string dir, List<InstructFileModel> files, string extension = "pdf")
     {
         if (string.IsNullOrWhiteSpace(dir) || files.IsNullOrEmpty())
         {
@@ -90,32 +90,33 @@ public partial class FileInstructService
         {
             try
             {
-                var bytes = new byte[0];
+                var binary = BinaryData.Empty;
                 if (!string.IsNullOrEmpty(file.FileUrl))
                 {
                     var http = _services.GetRequiredService<IHttpClientFactory>();
                     using var client = http.CreateClient();
-                    bytes = await client.GetByteArrayAsync(file.FileUrl);
+                    var bytes = await client.GetByteArrayAsync(file.FileUrl);
+                    binary = BinaryData.FromBytes(bytes);
                 }
                 else if (!string.IsNullOrEmpty(file.FileData))
                 {
-                    (_, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
+                    (_, binary) = FileUtility.GetFileInfoFromData(file.FileData);
                 }
 
-                if (!bytes.IsNullOrEmpty())
+                if (!binary.IsEmpty)
                 {
                     var guid = Guid.NewGuid().ToString();
                     var fileDir = _fileStorage.BuildDirectory(dir, guid);
-                    DeleteIfExistDirectory(fileDir, true);
+                    DeleteIfExistDirectory(fileDir, createNew: true);
 
                     var outputDir = _fileStorage.BuildDirectory(fileDir, $"{guid}.{extension}");
-                    _fileStorage.SaveFileBytesToPath(outputDir, bytes);
+                    _fileStorage.SaveFileBytesToPath(outputDir, binary);
                     locs.Add(outputDir);
                 }
             }
             catch (Exception ex)
             {
-                _logger.LogWarning(ex, $"Error when saving pdf file.");
+                _logger.LogWarning(ex, $"Error when saving {extension} file.");
                 continue;
             }
         }
diff --git a/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.cs b/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.cs
index 9ff3b46a..98321347 100644
--- a/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.cs
+++ b/src/Infrastructure/BotSharp.Core/Files/Services/Instruct/FileInstructService.cs
@@ -32,21 +32,22 @@ public partial class FileInstructService : IFileInstructService
         }
     }
 
-    private async Task<byte[]> DownloadFile(InstructFileModel file)
+    private async Task<BinaryData> DownloadFile(InstructFileModel file)
     {
-        var bytes = new byte[0];
+        var binary = BinaryData.Empty;
         if (!string.IsNullOrEmpty(file.FileUrl))
         {
             var http = _services.GetRequiredService<IHttpClientFactory>();
             using var client = http.CreateClient();
-            bytes = await client.GetByteArrayAsync(file.FileUrl);
+            var bytes = await client.GetByteArrayAsync(file.FileUrl);
+            binary = BinaryData.FromBytes(bytes);
         }
         else if (!string.IsNullOrEmpty(file.FileData))
         {
-            (_, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
+            (_, binary) = FileUtility.GetFileInfoFromData(file.FileData);
         }
 
-        return bytes;
+        return binary;
     }
 
     private async Task<string?> GetAgentTemplate(string agentId, string? templateName)
diff --git a/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.Common.cs b/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.Common.cs
index b16c2c2c..80a10dee 100644
--- a/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.Common.cs
+++ b/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.Common.cs
@@ -30,12 +30,12 @@ public partial class LocalFileStorageService
         return Directory.GetFiles(path);
     }
 
-    public byte[] GetFileBytes(string fileStorageUrl)
+    public BinaryData GetFileBytes(string fileStorageUrl)
     {
         using var stream = File.OpenRead(fileStorageUrl);
         var bytes = new byte[stream.Length];
         stream.Read(bytes, 0, (int)stream.Length);
-        return bytes;
+        return BinaryData.FromBytes(bytes);
     }
 
     public bool SaveFileStreamToPath(string filePath, Stream stream)
@@ -49,11 +49,11 @@ public partial class LocalFileStorageService
         return true;
     }
 
-    public bool SaveFileBytesToPath(string filePath, byte[] bytes)
+    public bool SaveFileBytesToPath(string filePath, BinaryData binary)
     {
         using (var fs = new FileStream(filePath, FileMode.Create))
         {
-            fs.Write(bytes, 0, bytes.Length);
+            fs.Write(binary.ToArray(), 0, binary.Length);
             fs.Flush();
             fs.Close();
         }
diff --git a/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.Conversation.cs b/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.Conversation.cs
index c1accd30..9aac4df3 100644
--- a/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.Conversation.cs
+++ b/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.Conversation.cs
@@ -136,7 +136,7 @@ public partial class LocalFileStorageService
 
             try
             {
-                var (_, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
+                var (_, binary) = FileUtility.GetFileInfoFromData(file.FileData);
                 var subDir = Path.Combine(dir, source, $"{i + 1}");
                 if (!ExistDirectory(subDir))
                 {
@@ -145,7 +145,7 @@ public partial class LocalFileStorageService
 
                 using (var fs = new FileStream(Path.Combine(subDir, file.FileName), FileMode.Create))
                 {
-                    fs.Write(bytes, 0, bytes.Length);
+                    fs.Write(binary.ToArray(), 0, binary.Length);
                     fs.Flush(true);
                     fs.Close();
                     Thread.Sleep(100);
diff --git a/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.User.cs b/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.User.cs
index 21f522b2..9384bd83 100644
--- a/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.User.cs
+++ b/src/Infrastructure/BotSharp.Core/Files/Services/Storage/LocalFileStorageService.User.cs
@@ -34,8 +34,8 @@ public partial class LocalFileStorageService
             }
 
             dir = GetUserAvatarDir(user?.Id, createNewDir: true);
-            var (_, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
-            File.WriteAllBytes(Path.Combine(dir, file.FileName), bytes);
+            var (_, binary) = FileUtility.GetFileInfoFromData(file.FileData);
+            File.WriteAllBytes(Path.Combine(dir, file.FileName), binary.ToArray());
             return true;
         }
         catch (Exception ex)
diff --git a/src/Infrastructure/BotSharp.OpenAPI/Controllers/InstructModeController.cs b/src/Infrastructure/BotSharp.OpenAPI/Controllers/InstructModeController.cs
index 430a4563..71c67e7e 100644
--- a/src/Infrastructure/BotSharp.OpenAPI/Controllers/InstructModeController.cs
+++ b/src/Infrastructure/BotSharp.OpenAPI/Controllers/InstructModeController.cs
@@ -135,7 +135,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in reading images. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             return error;
         }
     }
@@ -170,7 +170,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in reading image upload. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             viewModel.Message = error;
             return viewModel;
         }
@@ -202,7 +202,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in image generation. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             imageViewModel.Message = error;
             return imageViewModel;
         }
@@ -239,7 +239,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in image variation. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             imageViewModel.Message = error;
             return imageViewModel;
         }
@@ -272,7 +272,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in image variation upload. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             imageViewModel.Message = error;
             return imageViewModel;
         }
@@ -306,7 +306,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in image edit. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             imageViewModel.Message = error;
             return imageViewModel;
         }
@@ -341,7 +341,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in image edit upload. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             imageViewModel.Message = error;
             return imageViewModel;
         }
@@ -377,7 +377,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in image mask edit. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             imageViewModel.Message = error;
             return imageViewModel;
         }
@@ -415,7 +415,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in image mask edit upload. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             imageViewModel.Message = error;
             return imageViewModel;
         }
@@ -446,7 +446,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in pdf completion. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             viewModel.Message = error;
             return viewModel;
         }
@@ -483,7 +483,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in pdf completion upload. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             viewModel.Message = error;
             return viewModel;
         }
@@ -519,7 +519,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in speech to text. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             viewModel.Message = error;
             return viewModel;
         }
@@ -553,7 +553,7 @@ public class InstructModeController : ControllerBase
         catch (Exception ex)
         {
             var error = $"Error in speech-to-text upload. {ex.Message}";
-            _logger.LogError(error);
+            _logger.LogError(ex, error);
             viewModel.Message = error;
             return viewModel;
         }
diff --git a/src/Infrastructure/BotSharp.OpenAPI/Controllers/UserController.cs b/src/Infrastructure/BotSharp.OpenAPI/Controllers/UserController.cs
index 88a10838..92e36f46 100644
--- a/src/Infrastructure/BotSharp.OpenAPI/Controllers/UserController.cs
+++ b/src/Infrastructure/BotSharp.OpenAPI/Controllers/UserController.cs
@@ -245,8 +245,8 @@ public class UserController : ControllerBase
     private FileContentResult BuildFileResult(string file)
     {
         var fileStorage = _services.GetRequiredService<IFileStorageService>();
-        var bytes = fileStorage.GetFileBytes(file);
-        return File(bytes, "application/octet-stream", Path.GetFileName(file));
+        var binary = fileStorage.GetFileBytes(file);
+        return File(binary.ToArray(), "application/octet-stream", Path.GetFileName(file));
     }
     #endregion
 }
diff --git a/src/Plugins/BotSharp.Plugin.AudioHandler/Functions/HandleAudioRequestFn.cs b/src/Plugins/BotSharp.Plugin.AudioHandler/Functions/HandleAudioRequestFn.cs
index f20a675a..a114c2fa 100644
--- a/src/Plugins/BotSharp.Plugin.AudioHandler/Functions/HandleAudioRequestFn.cs
+++ b/src/Plugins/BotSharp.Plugin.AudioHandler/Functions/HandleAudioRequestFn.cs
@@ -87,8 +87,8 @@ public class HandleAudioRequestFn : IFunctionCallback
             var fileName = Path.GetFileName(file.FileStorageUrl);
             if (!ParseAudioFileType(fileName)) continue;
 
-            var bytes = _fileStorage.GetFileBytes(file.FileStorageUrl);
-            using var stream = new MemoryStream(bytes);
+            var binary = _fileStorage.GetFileBytes(file.FileStorageUrl);
+            using var stream = binary.ToStream();
             stream.Position = 0;
 
             var result = await audioCompletion.TranscriptTextAsync(stream, fileName);
diff --git a/src/Plugins/BotSharp.Plugin.AudioHandler/Provider/NativeWhisperProvider.cs b/src/Plugins/BotSharp.Plugin.AudioHandler/Provider/NativeWhisperProvider.cs
index 5c8a12d1..8e4a59fe 100644
--- a/src/Plugins/BotSharp.Plugin.AudioHandler/Provider/NativeWhisperProvider.cs
+++ b/src/Plugins/BotSharp.Plugin.AudioHandler/Provider/NativeWhisperProvider.cs
@@ -89,8 +89,8 @@ public class NativeWhisperProvider : IAudioTranscription
                 DownloadModel(modelType, modelLoc);
             }
 
-            var bytes = _fileStorage.GetFileBytes(modelLoc);
-            _whisperProcessor = WhisperFactory.FromBuffer(bytes).CreateBuilder().WithLanguage("auto").Build();
+            var binary = _fileStorage.GetFileBytes(modelLoc);
+            _whisperProcessor = WhisperFactory.FromBuffer(binary.ToArray()).CreateBuilder().WithLanguage("auto").Build();
         }
         catch (Exception ex)
         {
diff --git a/src/Plugins/BotSharp.Plugin.AzureOpenAI/Providers/Chat/ChatCompletionProvider.cs b/src/Plugins/BotSharp.Plugin.AzureOpenAI/Providers/Chat/ChatCompletionProvider.cs
index 114ea69d..b2eaaf46 100644
--- a/src/Plugins/BotSharp.Plugin.AzureOpenAI/Providers/Chat/ChatCompletionProvider.cs
+++ b/src/Plugins/BotSharp.Plugin.AzureOpenAI/Providers/Chat/ChatCompletionProvider.cs
@@ -322,15 +322,15 @@ public class ChatCompletionProvider : IChatCompletion
                     {
                         if (!string.IsNullOrEmpty(file.FileData))
                         {
-                            var (contentType, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
-                            var contentPart = ChatMessageContentPart.CreateImagePart(BinaryData.FromBytes(bytes), contentType, ChatImageDetailLevel.Auto);
+                            var (contentType, binary) = FileUtility.GetFileInfoFromData(file.FileData);
+                            var contentPart = ChatMessageContentPart.CreateImagePart(binary, contentType, ChatImageDetailLevel.Auto);
                             contentParts.Add(contentPart);
                         }
                         else if (!string.IsNullOrEmpty(file.FileStorageUrl))
                         {
                             var contentType = FileUtility.GetFileContentType(file.FileStorageUrl);
-                            var bytes = fileStorage.GetFileBytes(file.FileStorageUrl);
-                            var contentPart = ChatMessageContentPart.CreateImagePart(BinaryData.FromBytes(bytes), contentType, ChatImageDetailLevel.Auto);
+                            var binary = fileStorage.GetFileBytes(file.FileStorageUrl);
+                            var contentPart = ChatMessageContentPart.CreateImagePart(binary, contentType, ChatImageDetailLevel.Auto);
                             contentParts.Add(contentPart);
                         }
                         else if (!string.IsNullOrEmpty(file.FileUrl))
diff --git a/src/Plugins/BotSharp.Plugin.EmailHandler/Functions/HandleEmailSenderFn.cs b/src/Plugins/BotSharp.Plugin.EmailHandler/Functions/HandleEmailSenderFn.cs
index df46cdfe..35f817f4 100644
--- a/src/Plugins/BotSharp.Plugin.EmailHandler/Functions/HandleEmailSenderFn.cs
+++ b/src/Plugins/BotSharp.Plugin.EmailHandler/Functions/HandleEmailSenderFn.cs
@@ -90,8 +90,8 @@ public class HandleEmailSenderFn : IFunctionCallback
         {
             if (string.IsNullOrEmpty(file.FileStorageUrl)) continue;
 
-            var fileBytes = fileStorage.GetFileBytes(file.FileStorageUrl);
-            builder.Attachments.Add($"{file.FileName}.{file.FileExtension}", fileBytes, ContentType.Parse(file.ContentType));
+            var fileBinary = fileStorage.GetFileBytes(file.FileStorageUrl);
+            builder.Attachments.Add($"{file.FileName}.{file.FileExtension}", fileBinary.ToArray(), ContentType.Parse(file.ContentType));
             Thread.Sleep(100);
         }
     }
diff --git a/src/Plugins/BotSharp.Plugin.ExcelHandler/Functions/HandleExcelRequestFn.cs b/src/Plugins/BotSharp.Plugin.ExcelHandler/Functions/HandleExcelRequestFn.cs
index 270f6177..b65401fd 100644
--- a/src/Plugins/BotSharp.Plugin.ExcelHandler/Functions/HandleExcelRequestFn.cs
+++ b/src/Plugins/BotSharp.Plugin.ExcelHandler/Functions/HandleExcelRequestFn.cs
@@ -113,8 +113,8 @@ public class HandleExcelRequestFn : IFunctionCallback
 
             _currentFileName = Path.GetFileName(file.FileStorageUrl);
 
-            var bytes = _fileStorage.GetFileBytes(file.FileStorageUrl);
-            var workbook = ConvertToWorkBook(bytes);
+            var binary = _fileStorage.GetFileBytes(file.FileStorageUrl);
+            var workbook = ConvertToWorkBook(binary.ToArray());
 
             var currentCommandList = _mySqlService.WriteExcelDataToDB(workbook);
             sqlCommandList.AddRange(currentCommandList);
diff --git a/src/Plugins/BotSharp.Plugin.FileHandler/Functions/EditImageFn.cs b/src/Plugins/BotSharp.Plugin.FileHandler/Functions/EditImageFn.cs
index 2895f152..aed98fea 100644
--- a/src/Plugins/BotSharp.Plugin.FileHandler/Functions/EditImageFn.cs
+++ b/src/Plugins/BotSharp.Plugin.FileHandler/Functions/EditImageFn.cs
@@ -77,9 +77,8 @@ public class EditImageFn : IFunctionCallback
             };
 
             var fileStorage = _services.GetRequiredService<IFileStorageService>();
-            var fileBytes = fileStorage.GetFileBytes(image.FileStorageUrl);
-            using var stream = new MemoryStream();
-            stream.Write(fileBytes);
+            var fileBinary = fileStorage.GetFileBytes(image.FileStorageUrl);
+            using var stream = fileBinary.ToStream();
             stream.Position = 0;
             var result = await completion.GetImageEdits(agent, dialog, stream, image.FileName ?? string.Empty);
             stream.Close();
diff --git a/src/Plugins/BotSharp.Plugin.GoogleAI/Providers/Chat/GeminiChatCompletionProvider.cs b/src/Plugins/BotSharp.Plugin.GoogleAI/Providers/Chat/GeminiChatCompletionProvider.cs
index 9a23d817..a0e7cc17 100644
--- a/src/Plugins/BotSharp.Plugin.GoogleAI/Providers/Chat/GeminiChatCompletionProvider.cs
+++ b/src/Plugins/BotSharp.Plugin.GoogleAI/Providers/Chat/GeminiChatCompletionProvider.cs
@@ -307,26 +307,26 @@ public class GeminiChatCompletionProvider : IChatCompletion
                     {
                         if (!string.IsNullOrEmpty(file.FileData))
                         {
-                            var (contentType, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
+                            var (contentType, binary) = FileUtility.GetFileInfoFromData(file.FileData);
                             contentParts.Add(new Part()
                             {
                                 InlineData = new()
                                 {
-                                    MimeType = contentType,
-                                    Data = Convert.ToBase64String(bytes)
+                                    MimeType = contentType ?? file.ContentType,
+                                    Data = Convert.ToBase64String(binary.ToArray())
                                 }
                             });
                         }
                         else if (!string.IsNullOrEmpty(file.FileStorageUrl))
                         {
                             var contentType = FileUtility.GetFileContentType(file.FileStorageUrl);
-                            var bytes = fileStorage.GetFileBytes(file.FileStorageUrl);
+                            var binary = fileStorage.GetFileBytes(file.FileStorageUrl);
                             contentParts.Add(new Part()
                             {
                                 InlineData = new()
                                 {
                                     MimeType = contentType,
-                                    Data = Convert.ToBase64String(bytes)
+                                    Data = Convert.ToBase64String(binary.ToArray())
                                 }
                             });
                         }
diff --git a/src/Plugins/BotSharp.Plugin.KnowledgeBase/Services/KnowledgeService.Document.cs b/src/Plugins/BotSharp.Plugin.KnowledgeBase/Services/KnowledgeService.Document.cs
index a2461f18..491261d8 100644
--- a/src/Plugins/BotSharp.Plugin.KnowledgeBase/Services/KnowledgeService.Document.cs
+++ b/src/Plugins/BotSharp.Plugin.KnowledgeBase/Services/KnowledgeService.Document.cs
@@ -48,12 +48,12 @@ public partial class KnowledgeService
             try
             {
                 // Get document info
-                var (contentType, bytes) = await GetFileInfo(file);
-                var contents = await GetFileContent(contentType, bytes, option ?? ChunkOption.Default());
+                var (contentType, binary) = await GetFileInfo(file);
+                var contents = await GetFileContent(contentType, binary, option ?? ChunkOption.Default());
                 
                 // Save document
                 var fileId = Guid.NewGuid();
-                var saved = SaveDocument(collectionName, vectorStoreProvider, fileId, file.FileName, bytes);
+                var saved = SaveDocument(collectionName, vectorStoreProvider, fileId, file.FileName, binary);
                 if (!saved)
                 {
                     failedFiles.Add(file.FileName);
@@ -342,11 +342,11 @@ public partial class KnowledgeService
     /// </summary>
     /// <param name="file"></param>
     /// <returns></returns>
-    private async Task<(string, byte[])> GetFileInfo(ExternalFileModel file)
+    private async Task<(string, BinaryData)> GetFileInfo(ExternalFileModel file)
     {
         if (file == null)
         {
-            return (string.Empty, new byte[0]);
+            return (string.Empty, BinaryData.Empty);
         }
 
         if (!string.IsNullOrWhiteSpace(file.FileUrl))
@@ -355,37 +355,38 @@ public partial class KnowledgeService
             var contentType = FileUtility.GetFileContentType(file.FileName);
             using var client = http.CreateClient();
             var bytes = await client.GetByteArrayAsync(file.FileUrl);
-            return (contentType, bytes);
+            return (contentType, BinaryData.FromBytes(bytes));
         }
         else if (!string.IsNullOrWhiteSpace(file.FileData))
         {
-            var (contentType, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
-            return (contentType, bytes);
+            var (contentType, binary) = FileUtility.GetFileInfoFromData(file.FileData);
+            return (contentType, binary);
         }
 
-        return (string.Empty, new byte[0]);
+        return (string.Empty, BinaryData.Empty);
     }
 
     #region Read doc content
-    private async Task<IEnumerable<string>> GetFileContent(string contentType, byte[] bytes, ChunkOption option)
+    private async Task<IEnumerable<string>> GetFileContent(string contentType, BinaryData binary, ChunkOption option)
     {
         IEnumerable<string> results = new List<string>();
 
         if (contentType.IsEqualTo(MediaTypeNames.Text.Plain))
         {
-            results = await ReadTxt(bytes, option);
+            results = await ReadTxt(binary, option);
         }
         else if (contentType.IsEqualTo(MediaTypeNames.Application.Pdf))
         {
-            results = await ReadPdf(bytes);
+            results = await ReadPdf(binary);
         }
         
         return results;
     }
 
-    private async Task<IEnumerable<string>> ReadTxt(byte[] bytes, ChunkOption option)
+    private async Task<IEnumerable<string>> ReadTxt(BinaryData binary, ChunkOption option)
     {
-        using var stream = new MemoryStream(bytes);
+        using var stream = binary.ToStream();
+        stream.Position = 0;
         using var reader = new StreamReader(stream);
         var content = await reader.ReadToEndAsync();
         reader.Close();
@@ -395,18 +396,17 @@ public partial class KnowledgeService
         return lines;
     }
 
-    private async Task<IEnumerable<string>> ReadPdf(byte[] bytes)
+    private async Task<IEnumerable<string>> ReadPdf(BinaryData binary)
     {
         return Enumerable.Empty<string>();
     }
     #endregion
 
 
-    private bool SaveDocument(string collectionName, string vectorStoreProvider, Guid fileId, string fileName, byte[] bytes)
+    private bool SaveDocument(string collectionName, string vectorStoreProvider, Guid fileId, string fileName, BinaryData binary)
     {
         var fileStoreage = _services.GetRequiredService<IFileStorageService>();
-        var data = BinaryData.FromBytes(bytes);
-        var saved = fileStoreage.SaveKnowledgeBaseFile(collectionName, vectorStoreProvider, fileId, fileName, data);
+        var saved = fileStoreage.SaveKnowledgeBaseFile(collectionName, vectorStoreProvider, fileId, fileName, binary);
         return saved;
     }
 
diff --git a/src/Plugins/BotSharp.Plugin.MicrosoftExtensionsAI/MicrosoftExtensionsAIChatCompletionProvider.cs b/src/Plugins/BotSharp.Plugin.MicrosoftExtensionsAI/MicrosoftExtensionsAIChatCompletionProvider.cs
index d32fbece..d95a25ae 100644
--- a/src/Plugins/BotSharp.Plugin.MicrosoftExtensionsAI/MicrosoftExtensionsAIChatCompletionProvider.cs
+++ b/src/Plugins/BotSharp.Plugin.MicrosoftExtensionsAI/MicrosoftExtensionsAIChatCompletionProvider.cs
@@ -128,8 +128,8 @@ public sealed class MicrosoftExtensionsAIChatCompletionProvider : IChatCompletio
                         else if (!string.IsNullOrEmpty(file.FileStorageUrl))
                         {
                             var contentType = FileUtility.GetFileContentType(file.FileStorageUrl);
-                            var bytes = fileStorage!.GetFileBytes(file.FileStorageUrl);
-                            contents.Add(new DataContent(bytes, contentType));
+                            var binary = fileStorage!.GetFileBytes(file.FileStorageUrl);
+                            contents.Add(new DataContent(binary.ToMemory(), contentType));
                         }
                         else if (!string.IsNullOrEmpty(file.FileUrl))
                         {
diff --git a/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Chat/ChatCompletionProvider.cs b/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Chat/ChatCompletionProvider.cs
index d9591a0a..bfec9e3e 100644
--- a/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Chat/ChatCompletionProvider.cs
+++ b/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Chat/ChatCompletionProvider.cs
@@ -288,15 +288,15 @@ public class ChatCompletionProvider : IChatCompletion
                     {
                         if (!string.IsNullOrEmpty(file.FileData))
                         {
-                            var (contentType, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
-                            var contentPart = ChatMessageContentPart.CreateImagePart(BinaryData.FromBytes(bytes), contentType, ChatImageDetailLevel.Auto);
+                            var (contentType, binary) = FileUtility.GetFileInfoFromData(file.FileData);
+                            var contentPart = ChatMessageContentPart.CreateImagePart(binary, contentType ?? file.ContentType, ChatImageDetailLevel.Auto);
                             contentParts.Add(contentPart);
                         }
                         else if (!string.IsNullOrEmpty(file.FileStorageUrl))
                         {
                             var contentType = FileUtility.GetFileContentType(file.FileStorageUrl);
-                            var bytes = fileStorage.GetFileBytes(file.FileStorageUrl);
-                            var contentPart = ChatMessageContentPart.CreateImagePart(BinaryData.FromBytes(bytes), contentType, ChatImageDetailLevel.Auto);
+                            var binary = fileStorage.GetFileBytes(file.FileStorageUrl);
+                            var contentPart = ChatMessageContentPart.CreateImagePart(binary, contentType, ChatImageDetailLevel.Auto);
                             contentParts.Add(contentPart);
                         }
                         else if (!string.IsNullOrEmpty(file.FileUrl))
diff --git a/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Realtime/RealTimeCompletionProvider.cs b/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Realtime/RealTimeCompletionProvider.cs
index fd458744..8219bf1c 100644
--- a/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Realtime/RealTimeCompletionProvider.cs
+++ b/src/Plugins/BotSharp.Plugin.OpenAI/Providers/Realtime/RealTimeCompletionProvider.cs
@@ -632,15 +632,15 @@ public class RealTimeCompletionProvider : IRealTimeCompletion
                     {
                         if (!string.IsNullOrEmpty(file.FileData))
                         {
-                            var (contentType, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
-                            var contentPart = ChatMessageContentPart.CreateImagePart(BinaryData.FromBytes(bytes), contentType, ChatImageDetailLevel.Auto);
+                            var (contentType, binary) = FileUtility.GetFileInfoFromData(file.FileData);
+                            var contentPart = ChatMessageContentPart.CreateImagePart(binary, contentType, ChatImageDetailLevel.Auto);
                             contentParts.Add(contentPart);
                         }
                         else if (!string.IsNullOrEmpty(file.FileStorageUrl))
                         {
                             var contentType = FileUtility.GetFileContentType(file.FileStorageUrl);
-                            var bytes = fileStorage.GetFileBytes(file.FileStorageUrl);
-                            var contentPart = ChatMessageContentPart.CreateImagePart(BinaryData.FromBytes(bytes), contentType, ChatImageDetailLevel.Auto);
+                            var binary = fileStorage.GetFileBytes(file.FileStorageUrl);
+                            var contentPart = ChatMessageContentPart.CreateImagePart(binary, contentType, ChatImageDetailLevel.Auto);
                             contentParts.Add(contentPart);
                         }
                         else if (!string.IsNullOrEmpty(file.FileUrl))
diff --git a/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.Common.cs b/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.Common.cs
index 0659b0c8..fbc0a004 100644
--- a/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.Common.cs
+++ b/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.Common.cs
@@ -25,16 +25,17 @@ public partial class TencentCosService
         }
     }
 
-    public byte[] GetFileBytes(string fileStorageUrl)
+    public BinaryData GetFileBytes(string fileStorageUrl)
     {
         try
         {
-            return _cosClient.BucketClient.DownloadFileBytes(fileStorageUrl);
+            var bytes = _cosClient.BucketClient.DownloadFileBytes(fileStorageUrl);
+            return BinaryData.FromBytes(bytes);
         }
         catch (Exception ex)
         {
             _logger.LogWarning(ex, $"Error when getting file bytes (url: {fileStorageUrl}).");
-            return Array.Empty<byte>();
+            return BinaryData.Empty;
         }
     }
 
@@ -53,13 +54,13 @@ public partial class TencentCosService
         }
     }
 
-    public bool SaveFileBytesToPath(string filePath, byte[] bytes)
+    public bool SaveFileBytesToPath(string filePath, BinaryData binary)
     {
         if (string.IsNullOrEmpty(filePath)) return false;
 
         try
         {
-            return _cosClient.BucketClient.UploadBytes(filePath, bytes);
+            return _cosClient.BucketClient.UploadBytes(filePath, binary.ToArray());
         }
         catch (Exception ex)
         {
diff --git a/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.Conversation.cs b/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.Conversation.cs
index 4afec393..dfd6781f 100644
--- a/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.Conversation.cs
+++ b/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.Conversation.cs
@@ -132,9 +132,9 @@ public partial class TencentCosService
 
             try
             {
-                var (_, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
+                var (_, binary) = FileUtility.GetFileInfoFromData(file.FileData);
                 var subDir = $"{dir}/{source}/{i + 1}";
-                _cosClient.BucketClient.UploadBytes($"{subDir}/{file.FileName}", bytes);
+                _cosClient.BucketClient.UploadBytes($"{subDir}/{file.FileName}", binary.ToArray());
             }
             catch (Exception ex)
             {
diff --git a/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.User.cs b/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.User.cs
index 72076528..9d65d00f 100644
--- a/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.User.cs
+++ b/src/Plugins/BotSharp.Plugin.TencentCos/Services/TencentCosService.User.cs
@@ -28,11 +28,11 @@ public partial class TencentCosService
 
             if (string.IsNullOrEmpty(dir)) return false;
 
-            var (_, bytes) = FileUtility.GetFileInfoFromData(file.FileData);
+            var (_, binary) = FileUtility.GetFileInfoFromData(file.FileData);
             var extension = Path.GetExtension(file.FileName);
             var fileName = user?.Id == null ? file.FileName : $"{user?.Id}{extension}";
 
-            return _cosClient.BucketClient.UploadBytes($"{dir}/{fileName}", bytes);
+            return _cosClient.BucketClient.UploadBytes($"{dir}/{fileName}", binary.ToArray());
         }
         catch (Exception ex)
         {
diff --git a/tests/BotSharp.LLM.Tests/Core/NullFileStorageService.cs b/tests/BotSharp.LLM.Tests/Core/NullFileStorageService.cs
index 23514e4a..bb1d0c44 100644
--- a/tests/BotSharp.LLM.Tests/Core/NullFileStorageService.cs
+++ b/tests/BotSharp.LLM.Tests/Core/NullFileStorageService.cs
@@ -1,9 +1,9 @@
-using BotSharp.Abstraction.Files;
+using BotSharp.Abstraction.Files;
 using BotSharp.Abstraction.Files.Models;
 
 namespace BotSharp.Plugin.Google.Core
 {
-    public class NullFileStorageService:IFileStorageService
+    public class NullFileStorageService : IFileStorageService
     {
         public string GetDirectory(string conversationId)
         {
@@ -15,9 +15,10 @@ namespace BotSharp.Plugin.Google.Core
             return new List<string> { "FakeFile1.txt", "FakeFile2.txt" };
         }
 
-        public byte[] GetFileBytes(string fileStorageUrl)
+        public BinaryData GetFileBytes(string fileStorageUrl)
         {
-            return new byte[] { 0x00, 0x01, 0x02 };
+            var bytes = new byte[] { 0x00, 0x01, 0x02 };
+            return BinaryData.FromBytes(bytes);
         }
 
         public bool SaveFileStreamToPath(string filePath, Stream stream)
@@ -25,7 +26,7 @@ namespace BotSharp.Plugin.Google.Core
             return true;
         }
 
-        public bool SaveFileBytesToPath(string filePath, byte[] bytes)
+        public bool SaveFileBytesToPath(string filePath, BinaryData binary)
         {
             return true;
         }