diff --git a/src/HotChocolate/AspNetCore/src/Transport.Abstractions/FileReference.cs b/src/HotChocolate/AspNetCore/src/Transport.Abstractions/FileReference.cs
index 6c458f5702d..36b044dea12 100644
--- a/src/HotChocolate/AspNetCore/src/Transport.Abstractions/FileReference.cs
+++ b/src/HotChocolate/AspNetCore/src/Transport.Abstractions/FileReference.cs
@@ -10,6 +10,12 @@ public sealed class FileReference
 {
     private readonly Func<Stream> _openRead;
 
+    /// <inheritdoc cref="FileReference(Stream,string,string)"/>
+    public FileReference(Stream stream, string fileName)
+        : this(stream, fileName, null)
+    {
+    }
+
     /// <summary>
     /// Creates a new instance of <see cref="FileReference" />
     /// </summary>
@@ -19,13 +25,16 @@ public sealed class FileReference
     /// <param name="fileName">
     /// The file name.
     /// </param>
+    /// <param name="contentType">
+    /// The file content type.
+    /// </param>
     /// <exception cref="ArgumentNullException">
     /// <paramref name="stream"/> is <c>null</c>.
     /// </exception>
     /// <exception cref="ArgumentException">
     /// <paramref name="fileName"/> is <c>null</c>, empty or white space.
     /// </exception>
-    public FileReference(Stream stream, string fileName)
+    public FileReference(Stream stream, string fileName, string? contentType)
     {
         ArgumentNullException.ThrowIfNull(stream);
 
@@ -38,6 +47,13 @@ public FileReference(Stream stream, string fileName)
 
         _openRead = () => stream;
         FileName = fileName;
+        ContentType = contentType;
+    }
+
+    /// <inheritdoc cref="FileReference(Func{Stream},string,string)"/>
+    public FileReference(Func<Stream> openRead, string fileName)
+        : this(openRead, fileName, null)
+    {
     }
 
     /// <summary>
@@ -49,13 +65,16 @@ public FileReference(Stream stream, string fileName)
     /// <param name="fileName">
     /// The file name.
     /// </param>
+    /// <param name="contentType">
+    /// The file content type.
+    /// </param>
     /// <exception cref="ArgumentException">
     /// <paramref name="fileName"/> is <c>null</c>, empty or white space.
     /// </exception>
     /// <exception cref="ArgumentNullException">
     /// <paramref name="openRead"/> is <c>null</c>.
     /// </exception>
-    public FileReference(Func<Stream> openRead, string fileName)
+    public FileReference(Func<Stream> openRead, string fileName, string? contentType)
     {
         if (string.IsNullOrWhiteSpace(fileName))
         {
@@ -66,13 +85,19 @@ public FileReference(Func<Stream> openRead, string fileName)
 
         _openRead = openRead ?? throw new ArgumentNullException(nameof(openRead));
         FileName = fileName;
+        ContentType = contentType;
     }
 
     /// <summary>
-    /// The file name eg. <c>foo.txt</c>.
+    /// The file name e.g. <c>"foo.txt"</c>.
     /// </summary>
     public string FileName { get; }
 
+    /// <summary>
+    /// The content type of the file e.g. <c>"application/pdf"</c>.
+    /// </summary>
+    public string? ContentType { get; }
+
     /// <summary>
     /// Opens the file stream.
     /// </summary>
diff --git a/src/HotChocolate/AspNetCore/src/Transport.Http/DefaultGraphQLHttpClient.cs b/src/HotChocolate/AspNetCore/src/Transport.Http/DefaultGraphQLHttpClient.cs
index 77196d02e2c..fc13218585c 100644
--- a/src/HotChocolate/AspNetCore/src/Transport.Http/DefaultGraphQLHttpClient.cs
+++ b/src/HotChocolate/AspNetCore/src/Transport.Http/DefaultGraphQLHttpClient.cs
@@ -215,8 +215,13 @@ private static HttpContent CreateMultipartContent(
 
         foreach (var fileInfo in fileInfos)
         {
-            var file = new StreamContent(fileInfo.File.OpenRead());
-            form.Add(file, fileInfo.Name, fileInfo.File.FileName);
+            var fileContent = new StreamContent(fileInfo.File.OpenRead());
+            if (!string.IsNullOrEmpty(fileInfo.File.ContentType))
+            {
+                fileContent.Headers.ContentType = new MediaTypeHeaderValue(fileInfo.File.ContentType);
+            }
+
+            form.Add(fileContent, fileInfo.Name, fileInfo.File.FileName);
         }
 
         return form;
diff --git a/src/HotChocolate/AspNetCore/test/Transport.Http.Tests/GraphQLHttpClientTests.cs b/src/HotChocolate/AspNetCore/test/Transport.Http.Tests/GraphQLHttpClientTests.cs
index 02e18271606..a3f9b952aea 100644
--- a/src/HotChocolate/AspNetCore/test/Transport.Http.Tests/GraphQLHttpClientTests.cs
+++ b/src/HotChocolate/AspNetCore/test/Transport.Http.Tests/GraphQLHttpClientTests.cs
@@ -1,4 +1,5 @@
 using System.Net;
+using System.Text;
 using System.Text.Json;
 using HotChocolate.AspNetCore.Tests.Utilities;
 using HotChocolate.Language;
@@ -881,13 +882,19 @@ public async Task Get_Subscription_Over_SSE_With_Errors()
         await snapshot.MatchMarkdownAsync(cts.Token);
     }
 
-    [Fact]
-    public async Task Post_GraphQL_FileUpload()
+    [Theory]
+    [InlineData((string?)null)]
+    [InlineData("application/pdf")]
+    public async Task Post_GraphQL_FileUpload(string? contentType)
     {
         // arrange
         using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5000));
-        using var testServer = CreateStarWarsServer();
-        var httpClient = testServer.CreateClient();
+        var server = CreateStarWarsServer(
+            configureServices: s => s
+                .AddGraphQLServer("test")
+                .AddType<UploadType>()
+                .AddQueryType<UploadTestQuery>());
+        var httpClient = server.CreateClient();
         var client = new DefaultGraphQLHttpClient(httpClient);
 
         var stream = new MemoryStream("abc"u8.ToArray());
@@ -895,15 +902,19 @@ public async Task Post_GraphQL_FileUpload()
         var operation = new OperationRequest(
             """
             query ($upload: Upload!) {
-              singleUpload(file: $upload)
+              singleInfoUpload(file: $upload) {
+                name
+                content
+                contentType
+              }
             }
             """,
             variables: new Dictionary<string, object?>
             {
-                ["upload"] = new FileReference(() => stream, "test.txt")
+                ["upload"] = new FileReference(() => stream, "test.txt", contentType)
             });
 
-        var requestUri = new Uri(CreateUrl("/upload"));
+        var requestUri = new Uri(CreateUrl("/test"));
 
         var request = new GraphQLHttpRequest(operation, requestUri)
         {
@@ -917,10 +928,14 @@ public async Task Post_GraphQL_FileUpload()
         // assert
         using var body = await response.ReadAsResultAsync(cts.Token);
         body.MatchInlineSnapshot(
-            """
+            $$$"""
             {
               "data": {
-                "singleUpload": "abc"
+                "singleInfoUpload": {
+                  "name": "test.txt",
+                  "content": "abc",
+                  "contentType": "{{{contentType}}}"
+                }
               }
             }
             """);
@@ -1006,4 +1021,26 @@ public async IAsyncEnumerable<string> CreateStream()
         public string OnError([EventMessage] string message)
             => message;
     }
+
+    public class UploadTestQuery
+    {
+        public async Task<FileInfoOutput> SingleInfoUpload(IFile file)
+        {
+            await using var stream = file.OpenReadStream();
+            using var sr = new StreamReader(stream, Encoding.UTF8);
+            return new FileInfoOutput
+            {
+                Content = await sr.ReadToEndAsync(),
+                ContentType = file.ContentType ?? string.Empty,
+                Name = file.Name
+            };
+        }
+
+        public class FileInfoOutput
+        {
+            public string? Content { get; init; }
+            public string? ContentType { get; init; }
+            public string? Name { get; init; }
+        }
+    }
 }
diff --git a/src/StrawberryShake/Client/src/Core/Upload.cs b/src/StrawberryShake/Client/src/Core/Upload.cs
index 92e2c670506..4108b4e8822 100644
--- a/src/StrawberryShake/Client/src/Core/Upload.cs
+++ b/src/StrawberryShake/Client/src/Core/Upload.cs
@@ -5,13 +5,20 @@ namespace StrawberryShake;
 /// </summary>
 public readonly struct Upload
 {
+    /// <inheritdoc cref="Upload(Stream, string, string?)"/>
+    public Upload(Stream content, string fileName)
+        : this(content, fileName, null)
+    {
+    }
+
     /// <summary>
-    /// Creates a new instance of Upload
+    /// Creates a new instance of the Upload-scalar.
     /// </summary>
-    public Upload(Stream content, string fileName)
+    public Upload(Stream content, string fileName, string? contentType)
     {
         Content = content;
         FileName = fileName;
+        ContentType = contentType;
     }
 
     /// <summary>
@@ -23,4 +30,12 @@ public Upload(Stream content, string fileName)
     /// The name of the file
     /// </summary>
     public string FileName { get; }
+
+    /// <summary>
+    /// The optional MIME type of the file.
+    /// </summary>
+    /// <remarks>
+    /// If specified, this value is applied as the HTTP Content-Type header.
+    /// </remarks>
+    public string? ContentType { get; }
 }
diff --git a/src/StrawberryShake/Client/src/Transport.Http/HttpConnection.cs b/src/StrawberryShake/Client/src/Transport.Http/HttpConnection.cs
index 25ab30e9f07..4bbd073ce13 100644
--- a/src/StrawberryShake/Client/src/Transport.Http/HttpConnection.cs
+++ b/src/StrawberryShake/Client/src/Transport.Http/HttpConnection.cs
@@ -241,7 +241,7 @@ private static void MapVariables(List<object?> variables)
             {
                 case Dictionary<string, object> result:
                     result[currentPath] =
-                        new FileReference(upload.Value.Content, upload.Value.FileName);
+                        new FileReference(upload.Value.Content, upload.Value.FileName, upload.Value.ContentType);
                     break;
 
                 case List<object> array:
@@ -258,7 +258,7 @@ private static void MapVariables(List<object?> variables)
                     }
 
                     array[arrayIndex] =
-                        new FileReference(upload.Value.Content, upload.Value.FileName);
+                        new FileReference(upload.Value.Content, upload.Value.FileName, upload.Value.ContentType);
 
                     break;
 
diff --git a/src/StrawberryShake/Client/src/Transport.InMemory/DependencyInjection/InMemoryClient.cs b/src/StrawberryShake/Client/src/Transport.InMemory/DependencyInjection/InMemoryClient.cs
index 8740fd55577..32c29a389fb 100644
--- a/src/StrawberryShake/Client/src/Transport.InMemory/DependencyInjection/InMemoryClient.cs
+++ b/src/StrawberryShake/Client/src/Transport.InMemory/DependencyInjection/InMemoryClient.cs
@@ -129,7 +129,7 @@ await interceptor
             default:
                 if (fileValue is Upload upload)
                 {
-                    return new StreamFile(upload.FileName, () => upload.Content);
+                    return new StreamFile(upload.FileName, () => upload.Content, null, upload.ContentType);
                 }
 
                 return variables;
diff --git a/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadScalarTest.cs b/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadScalarTest.cs
index 28765ded0db..0399ac93649 100644
--- a/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadScalarTest.cs
+++ b/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadScalarTest.cs
@@ -12,8 +12,10 @@ public UploadScalarTest(TestServerFactory serverFactory) : base(serverFactory)
     {
     }
 
-    [Fact]
-    public async Task Execute_UploadScalar_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_UploadScalar_Argument(string? contentType)
     {
         // arrange
         var ct = new CancellationTokenSource(20_000).Token;
@@ -24,7 +26,7 @@ public async Task Execute_UploadScalar_Argument()
         // act
         var result = await client.TestUpload.ExecuteAsync(
             "foo",
-            new Upload(data, "test-file"),
+            new Upload(data, "test-file", contentType),
             null,
             null,
             null,
@@ -33,11 +35,13 @@ public async Task Execute_UploadScalar_Argument()
             cancellationToken: ct);
 
         // assert
-        Assert.Equal("test-file:a", result.Data!.Upload);
+        Assert.Equal($"[test-file:a|{contentType}]", result.Data!.Upload);
     }
 
-    [Fact]
-    public async Task Execute_UploadScalarList_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_UploadScalarList_Argument(string? contentType)
     {
         // arrange
         var ct = new CancellationTokenSource(20_000).Token;
@@ -50,7 +54,7 @@ public async Task Execute_UploadScalarList_Argument()
         var result = await client.TestUpload.ExecuteAsync(
             "foo",
             null,
-            new Upload?[] { new Upload(dataA, "A"), new Upload(dataB, "B") },
+            new Upload?[] { new Upload(dataA, "A", contentType), new Upload(dataB, "B", contentType) },
             null,
             null,
             null,
@@ -58,11 +62,13 @@ public async Task Execute_UploadScalarList_Argument()
             cancellationToken: ct);
 
         // assert
-        Assert.Equal("A:a,B:b", result.Data!.Upload);
+        Assert.Equal($"[A:a|{contentType}],[B:b|{contentType}]", result.Data!.Upload);
     }
 
-    [Fact]
-    public async Task Execute_UploadScalarNested_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_UploadScalarNested_Argument(string? contentType)
     {
         // arrange
         var ct = new CancellationTokenSource(20_000).Token;
@@ -76,18 +82,20 @@ public async Task Execute_UploadScalarNested_Argument()
             "foo",
             null,
             null,
-            new[] { new Upload?[] { new Upload(dataA, "A"), new Upload(dataB, "B") } },
+            new[] { new Upload?[] { new Upload(dataA, "A", contentType), new Upload(dataB, "B", contentType) } },
             null,
             null,
             null,
             cancellationToken: ct);
 
         // assert
-        Assert.Equal("A:a,B:b", result.Data!.Upload);
+        Assert.Equal($"[A:a|{contentType}],[B:b|{contentType}]", result.Data!.Upload);
     }
 
-    [Fact]
-    public async Task Execute_Input_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_Input_Argument(string? contentType)
     {
         // arrange
         var ct = new CancellationTokenSource(20_000).Token;
@@ -105,7 +113,7 @@ public async Task Execute_Input_Argument()
             {
                 Bar = new BarInput()
                 {
-                    Baz = new BazInput() { File = new Upload(data, "test-file") }
+                    Baz = new BazInput() { File = new Upload(data, "test-file", contentType) }
                 }
             },
             null,
@@ -113,11 +121,13 @@ public async Task Execute_Input_Argument()
             cancellationToken: ct);
 
         // assert
-        Assert.Equal("test-file:a", result.Data!.Upload);
+        Assert.Equal($"[test-file:a|{contentType}]", result.Data!.Upload);
     }
 
-    [Fact]
-    public async Task Execute_InputList_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_InputList_Argument(string? contentType)
     {
         // arrange
         var ct = new CancellationTokenSource(20_000).Token;
@@ -138,14 +148,14 @@ public async Task Execute_InputList_Argument()
                 {
                     Bar = new BarInput()
                     {
-                        Baz = new BazInput() { File = new Upload(dataA, "A") }
+                        Baz = new BazInput() { File = new Upload(dataA, "A", contentType) }
                     }
                 },
                 new TestInput()
                 {
                     Bar = new BarInput()
                     {
-                        Baz = new BazInput() { File = new Upload(dataB, "B") }
+                        Baz = new BazInput() { File = new Upload(dataB, "B", contentType) }
                     }
                 }
             },
@@ -153,11 +163,13 @@ public async Task Execute_InputList_Argument()
             cancellationToken: ct);
 
         // assert
-        Assert.Equal("A:a,B:b", result.Data!.Upload);
+        Assert.Equal($"[A:a|{contentType}],[B:b|{contentType}]", result.Data!.Upload);
     }
 
-    [Fact]
-    public async Task Execute_InputNested_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_InputNested_Argument(string? contentType)
     {
         // arrange
         var ct = new CancellationTokenSource(20_000).Token;
@@ -182,14 +194,14 @@ public async Task Execute_InputNested_Argument()
                     {
                         Bar = new BarInput()
                         {
-                            Baz = new BazInput() { File = new Upload(dataA, "A") }
+                            Baz = new BazInput() { File = new Upload(dataA, "A", contentType) }
                         }
                     },
                     new TestInput()
                     {
                         Bar = new BarInput()
                         {
-                            Baz = new BazInput() { File = new Upload(dataB, "B") }
+                            Baz = new BazInput() { File = new Upload(dataB, "B", contentType) }
                         }
                     }
                 }
@@ -197,7 +209,7 @@ public async Task Execute_InputNested_Argument()
             cancellationToken: ct);
 
         // assert
-        Assert.Equal("A:a,B:b", result.Data!.Upload);
+        Assert.Equal($"[A:a|{contentType}],[B:b|{contentType}]", result.Data!.Upload);
     }
 
     public static UploadScalarClient CreateClient(IWebHost host, int port)
@@ -218,8 +230,10 @@ public static UploadScalarClient CreateClient(IWebHost host, int port)
         return services.GetRequiredService<UploadScalarClient>();
     }
 
-    [Fact]
-    public async Task Execute_ListWorksWithNull()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_ListWorksWithNull(string? contentType)
     {
         // arrange
         var ct = new CancellationTokenSource(20_000).Token;
@@ -232,7 +246,7 @@ public async Task Execute_ListWorksWithNull()
         var result = await client.TestUpload.ExecuteAsync(
             "foo",
             null,
-            new Upload?[] { new Upload(dataA, "A"), null, new Upload(dataB, "B") },
+            new Upload?[] { new Upload(dataA, "A", contentType), null, new Upload(dataB, "B", contentType) },
             null,
             null,
             null,
@@ -240,6 +254,6 @@ public async Task Execute_ListWorksWithNull()
             cancellationToken: ct);
 
         // assert
-        Assert.Equal("A:a,null,B:b", result.Data!.Upload);
+        Assert.Equal($"[A:a|{contentType}],[|],[B:b|{contentType}]", result.Data!.Upload);
     }
 }
diff --git a/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadScalar_InMemoryTest.cs b/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadScalar_InMemoryTest.cs
index d0c1f81b363..6e00e0c19aa 100644
--- a/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadScalar_InMemoryTest.cs
+++ b/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadScalar_InMemoryTest.cs
@@ -10,8 +10,10 @@ public UploadScalarInMemoryTest(TestServerFactory serverFactory) : base(serverFa
     {
     }
 
-    [Fact]
-    public async Task Execute_UploadScalar_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_UploadScalar_Argument(string? contentType)
     {
         // arrange
         var client = CreateClient();
@@ -20,7 +22,7 @@ public async Task Execute_UploadScalar_Argument()
         // act
         var result = await client.TestUpload.ExecuteAsync(
             "foo",
-            new Upload(data, "test-file"),
+            new Upload(data, "test-file", contentType),
             null,
             null,
             null,
@@ -28,11 +30,13 @@ public async Task Execute_UploadScalar_Argument()
             null);
 
         // assert
-        Assert.Equal("test-file:a", result.Data!.Upload);
+        Assert.Equal($"[test-file:a|{contentType}]", result.Data!.Upload);
     }
 
-    [Fact]
-    public async Task Execute_UploadScalarList_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_UploadScalarList_Argument(string? contentType)
     {
         // arrange
         var client = CreateClient();
@@ -43,18 +47,20 @@ public async Task Execute_UploadScalarList_Argument()
         var result = await client.TestUpload.ExecuteAsync(
             "foo",
             null,
-            new Upload?[] { new Upload(dataA, "A"), new Upload(dataB, "B") },
+            new Upload?[] { new Upload(dataA, "A", contentType), new Upload(dataB, "B", contentType) },
             null,
             null,
             null,
             null);
 
         // assert
-        Assert.Equal("A:a,B:b", result.Data!.Upload);
+        Assert.Equal($"[A:a|{contentType}],[B:b|{contentType}]", result.Data!.Upload);
     }
 
-    [Fact]
-    public async Task Execute_UploadScalarNested_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_UploadScalarNested_Argument(string? contentType)
     {
         // arrange
         var client = CreateClient();
@@ -66,17 +72,19 @@ public async Task Execute_UploadScalarNested_Argument()
             "foo",
             null,
             null,
-            new[] { new Upload?[] { new Upload(dataA, "A"), new Upload(dataB, "B") } },
+            new[] { new Upload?[] { new Upload(dataA, "A", contentType), new Upload(dataB, "B", contentType) } },
             null,
             null,
             null);
 
         // assert
-        Assert.Equal("A:a,B:b", result.Data!.Upload);
+        Assert.Equal($"[A:a|{contentType}],[B:b|{contentType}]", result.Data!.Upload);
     }
 
-    [Fact]
-    public async Task Execute_Input_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_Input_Argument(string? contentType)
     {
         // arrange
         var client = CreateClient();
@@ -92,18 +100,20 @@ public async Task Execute_Input_Argument()
             {
                 Bar = new BarInput()
                 {
-                    Baz = new BazInput() { File = new Upload(data, "test-file") }
+                    Baz = new BazInput() { File = new Upload(data, "test-file", contentType) }
                 }
             },
             null,
             null);
 
         // assert
-        Assert.Equal("test-file:a", result.Data!.Upload);
+        Assert.Equal($"[test-file:a|{contentType}]", result.Data!.Upload);
     }
 
-    [Fact]
-    public async Task Execute_InputList_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_InputList_Argument(string? contentType)
     {
         // arrange
         var client = CreateClient();
@@ -122,25 +132,27 @@ public async Task Execute_InputList_Argument()
                 {
                     Bar = new BarInput()
                     {
-                        Baz = new BazInput() { File = new Upload(dataA, "A") }
+                        Baz = new BazInput() { File = new Upload(dataA, "A", contentType) }
                     }
                 },
                 new TestInput()
                 {
                     Bar = new BarInput()
                     {
-                        Baz = new BazInput() { File = new Upload(dataB, "B") }
+                        Baz = new BazInput() { File = new Upload(dataB, "B", contentType) }
                     }
                 }
             },
             null);
 
         // assert
-        Assert.Equal("A:a,B:b", result.Data!.Upload);
+        Assert.Equal($"[A:a|{contentType}],[B:b|{contentType}]", result.Data!.Upload);
     }
 
-    [Fact]
-    public async Task Execute_InputNested_Argument()
+    [Theory]
+    [InlineData(null)]
+    [InlineData("application/pdf")]
+    public async Task Execute_InputNested_Argument(string? contentType)
     {
         // arrange
         var client = CreateClient();
@@ -163,21 +175,21 @@ public async Task Execute_InputNested_Argument()
                     {
                         Bar = new BarInput()
                         {
-                            Baz = new BazInput() { File = new Upload(dataA, "A") }
+                            Baz = new BazInput() { File = new Upload(dataA, "A", contentType) }
                         }
                     },
                     new TestInput()
                     {
                         Bar = new BarInput()
                         {
-                            Baz = new BazInput() { File = new Upload(dataB, "B") }
+                            Baz = new BazInput() { File = new Upload(dataB, "B", contentType) }
                         }
                     }
                 }
             });
 
         // assert
-        Assert.Equal("A:a,B:b", result.Data!.Upload);
+        Assert.Equal($"[A:a|{contentType}],[B:b|{contentType}]", result.Data!.Upload);
     }
 
     public static UploadScalar_InMemoryClient CreateClient()
diff --git a/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadSchemaHelpers.cs b/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadSchemaHelpers.cs
index 09bd62d2af1..0d12fbec085 100644
--- a/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadSchemaHelpers.cs
+++ b/src/StrawberryShake/CodeGeneration/test/CodeGeneration.CSharp.Tests/Integration/UploadSchemaHelpers.cs
@@ -42,40 +42,43 @@ public string Upload(
         {
             if (single is not null)
             {
-                return single.ReadContents();
+                return Format(single);
             }
 
             if (list is not null)
             {
-                return string.Join(",", list.Select(x => x?.ReadContents() ?? "null"));
+                return string.Join(",", list.Select(Format));
             }
 
             if (nested is not null)
             {
                 return string.Join(",",
-                    nested.SelectMany(y => y!.Select(x => x?.ReadContents() ?? "null")));
+                    nested.SelectMany(y => y!.Select(Format)));
             }
 
             if (objectSingle is not null)
             {
-                return objectSingle.Bar!.Baz!.File!.ReadContents();
+                return Format(objectSingle.Bar!.Baz!.File);
             }
 
             if (objectList is not null)
             {
                 return string.Join(",",
-                    objectList.Select(x => x?.Bar!.Baz!.File!.ReadContents() ?? "null"));
+                    objectList.Select(x => Format(x?.Bar!.Baz!.File)));
             }
 
             if (objectNested is not null)
             {
                 return string.Join(",",
                     objectNested.SelectMany(y
-                        => y!.Select(x => x?.Bar!.Baz!.File!.ReadContents() ?? "null")));
+                        => y!.Select(x => Format(x?.Bar!.Baz!.File))));
             }
 
             return "error";
         }
+
+        private static string Format(IFile? file) =>
+            $"[{file?.ReadContents()}|{file?.ContentType}]";
     }
 
     public record Test(Bar? Bar);