diff --git a/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Application/Services/JiboCloudProtocolService.cs b/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Application/Services/JiboCloudProtocolService.cs
index a64747c..5d32034 100644
--- a/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Application/Services/JiboCloudProtocolService.cs
+++ b/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Application/Services/JiboCloudProtocolService.cs
@@ -1,4 +1,5 @@
 using System.Text;
+using System.Security.Cryptography;
 using System.Text.Json;
 using Jibo.Cloud.Application.Abstractions;
 using Jibo.Cloud.Domain.Models;
@@ -343,10 +344,15 @@ public sealed class JiboCloudProtocolService(ICloudStateStore stateStore, IMedia
         var meta = ReadObject(body, "meta") ?? new Dictionary<string, object?>(StringComparer.OrdinalIgnoreCase);
         var contentType = ReadHeader(envelope, "Content-Type") ?? "application/octet-stream";
         meta["contentType"] = contentType;
+        var bodyBytes = string.IsNullOrWhiteSpace(envelope.BodyText)
+            ? []
+            : Encoding.UTF8.GetBytes(envelope.BodyText);
+        meta["contentLength"] = bodyBytes.Length;
+        meta["contentSha256"] = Convert.ToHexString(SHA256.HashData(bodyBytes)).ToLowerInvariant();
         if (!string.IsNullOrWhiteSpace(envelope.BodyText)) meta["bodyText"] = envelope.BodyText;
 
         _mediaContentStore.StoreAsync(path, contentType,
-            string.IsNullOrWhiteSpace(envelope.BodyText) ? [] : Encoding.UTF8.GetBytes(envelope.BodyText),
+            bodyBytes,
             meta as IReadOnlyDictionary<string, object?>, CancellationToken.None).GetAwaiter().GetResult();
 
         return ProtocolDispatchResult.Ok(
@@ -743,4 +749,4 @@ public sealed class JiboCloudProtocolService(ICloudStateStore stateStore, IMedia
             return Task.FromResult<MediaContentSnapshot?>(null);
         }
     }
-}
\ No newline at end of file
+}
diff --git a/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Infrastructure/Media/AzureBlobMediaContentStore.cs b/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Infrastructure/Media/AzureBlobMediaContentStore.cs
index abddb0a..b2304da 100644
--- a/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Infrastructure/Media/AzureBlobMediaContentStore.cs
+++ b/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Infrastructure/Media/AzureBlobMediaContentStore.cs
@@ -1,4 +1,5 @@
 using System.Text.Json;
+using System.Security.Cryptography;
 using Azure.Storage.Blobs;
 using Jibo.Cloud.Application.Abstractions;
 
@@ -31,11 +32,17 @@ internal sealed class AzureBlobMediaContentStore : IMediaContentStore
         var metaBlob = _containerClient.GetBlobClient($"{relative}.json");
         await _containerClient.CreateIfNotExistsAsync(cancellationToken: cancellationToken);
         await contentBlob.UploadAsync(new MemoryStream(content), true, cancellationToken);
+        var manifestMeta = meta is null
+            ? new Dictionary<string, object?>(StringComparer.OrdinalIgnoreCase)
+            : new Dictionary<string, object?>(meta, StringComparer.OrdinalIgnoreCase);
+        manifestMeta["contentLength"] = content.Length;
+        manifestMeta["contentSha256"] = Convert.ToHexString(SHA256.HashData(content)).ToLowerInvariant();
+        manifestMeta["storedUtc"] = DateTimeOffset.UtcNow;
         var payload = JsonSerializer.Serialize(new
         {
             path,
             contentType,
-            meta
+            meta = manifestMeta
         }, JsonOptions);
         await metaBlob.UploadAsync(BinaryData.FromString(payload), true, cancellationToken);
     }
@@ -77,4 +84,4 @@ internal sealed class AzureBlobMediaContentStore : IMediaContentStore
             Meta = meta as IReadOnlyDictionary<string, object?> ?? new Dictionary<string, object?>(meta)
         };
     }
-}
\ No newline at end of file
+}
diff --git a/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Infrastructure/Media/FileMediaContentStore.cs b/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Infrastructure/Media/FileMediaContentStore.cs
index 5ce97a9..a8cd896 100644
--- a/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Infrastructure/Media/FileMediaContentStore.cs
+++ b/OpenJibo/src/Jibo.Cloud/dotnet/src/Jibo.Cloud.Infrastructure/Media/FileMediaContentStore.cs
@@ -1,4 +1,5 @@
 using System.Text.Json;
+using System.Security.Cryptography;
 using Jibo.Cloud.Application.Abstractions;
 
 namespace Jibo.Cloud.Infrastructure.Media;
@@ -29,11 +30,17 @@ internal sealed class FileMediaContentStore : IMediaContentStore
 
         Directory.CreateDirectory(Path.GetDirectoryName(contentPath)!);
         await File.WriteAllBytesAsync(contentPath, content, cancellationToken);
+        var manifestMeta = meta is null
+            ? new Dictionary<string, object?>(StringComparer.OrdinalIgnoreCase)
+            : new Dictionary<string, object?>(meta, StringComparer.OrdinalIgnoreCase);
+        manifestMeta["contentLength"] = content.Length;
+        manifestMeta["contentSha256"] = Convert.ToHexString(SHA256.HashData(content)).ToLowerInvariant();
+        manifestMeta["storedUtc"] = DateTimeOffset.UtcNow;
         var payload = new
         {
             path,
             contentType,
-            meta
+            meta = manifestMeta
         };
         await File.WriteAllTextAsync(metaPath, JsonSerializer.Serialize(payload, JsonOptions), cancellationToken);
     }
@@ -79,4 +86,4 @@ internal sealed class FileMediaContentStore : IMediaContentStore
             Meta = meta as IReadOnlyDictionary<string, object?> ?? new Dictionary<string, object?>(meta)
         };
     }
-}
\ No newline at end of file
+}
diff --git a/OpenJibo/tests/Jibo.Cloud.Tests/Protocol/JiboCloudProtocolServiceTests.cs b/OpenJibo/tests/Jibo.Cloud.Tests/Protocol/JiboCloudProtocolServiceTests.cs
index 3e13553..ff28a7c 100644
--- a/OpenJibo/tests/Jibo.Cloud.Tests/Protocol/JiboCloudProtocolServiceTests.cs
+++ b/OpenJibo/tests/Jibo.Cloud.Tests/Protocol/JiboCloudProtocolServiceTests.cs
@@ -1,3 +1,5 @@
+using System.Security.Cryptography;
+using System.Text;
 using System.Text.Json;
 using Jibo.Cloud.Application.Services;
 using Jibo.Cloud.Domain.Models;
@@ -420,6 +422,46 @@ public sealed class JiboCloudProtocolServiceTests
         Assert.Equal("binary-photo-placeholder", mediaGet.BodyText);
     }
 
+    [Fact]
+    public async Task MediaCreate_WritesBinaryManifestMetadataForSync()
+    {
+        var directoryPath = Path.Combine(Path.GetTempPath(), "OpenJibo.Media.Tests", Guid.NewGuid().ToString("N"));
+        var service = new JiboCloudProtocolService(new InMemoryCloudStateStore(),
+            new FileMediaContentStore(directoryPath));
+        const string bodyText = "binary-photo-placeholder";
+
+        var result = await service.DispatchAsync(new ProtocolEnvelope
+        {
+            HostName = "api.jibo.com",
+            Method = "POST",
+            ServicePrefix = "Media_20160725",
+            Operation = "Create",
+            Headers = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase)
+            {
+                ["Content-Type"] = "image/jpeg",
+                ["x-path"] = "photo-blob-manifest",
+                ["x-type"] = "image"
+            },
+            BodyText = bodyText
+        });
+
+        using var createdPayload = JsonDocument.Parse(result.BodyText);
+        var meta = createdPayload.RootElement.GetProperty("meta");
+        Assert.Equal(bodyText.Length, meta.GetProperty("contentLength").GetInt32());
+        Assert.Equal(
+            Convert.ToHexString(SHA256.HashData(Encoding.UTF8.GetBytes(bodyText))).ToLowerInvariant(),
+            meta.GetProperty("contentSha256").GetString());
+
+        var metaPath = Path.Combine(directoryPath, "photo-blob-manifest.json");
+        using var manifest = JsonDocument.Parse(await File.ReadAllTextAsync(metaPath));
+        var manifestMeta = manifest.RootElement.GetProperty("meta");
+        Assert.Equal(bodyText.Length, manifestMeta.GetProperty("contentLength").GetInt32());
+        Assert.Equal(
+            Convert.ToHexString(SHA256.HashData(Encoding.UTF8.GetBytes(bodyText))).ToLowerInvariant(),
+            manifestMeta.GetProperty("contentSha256").GetString());
+        Assert.True(manifestMeta.TryGetProperty("storedUtc", out _));
+    }
+
     [Fact]
     public async Task KeyCreateSymmetricKey_ReturnsKeyPayload()
     {
@@ -468,4 +510,4 @@ public sealed class JiboCloudProtocolServiceTests
         Assert.Contains(people,
             person => string.Equals(person.LoopId, store.GetLoops()[0].LoopId, StringComparison.OrdinalIgnoreCase));
     }
-}
\ No newline at end of file
+}