diff --git a/src/Libraries/Microsoft.Extensions.AI.Abstractions/Contents/HostedFileContent.cs b/src/Libraries/Microsoft.Extensions.AI.Abstractions/Contents/HostedFileContent.cs
index 5f0f13d8b24..cc9d8fd4e97 100644
--- a/src/Libraries/Microsoft.Extensions.AI.Abstractions/Contents/HostedFileContent.cs
+++ b/src/Libraries/Microsoft.Extensions.AI.Abstractions/Contents/HostedFileContent.cs
@@ -25,7 +25,7 @@ public sealed class HostedFileContent : AIContent
     /// <exception cref="ArgumentException"><paramref name="fileId"/> is empty or composed entirely of whitespace.</exception>
     public HostedFileContent(string fileId)
     {
-        FileId = fileId;
+        FileId = Throw.IfNullOrWhitespace(fileId);
     }
 
     /// <summary>
diff --git a/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Contents/HostedFileContentTests.cs b/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Contents/HostedFileContentTests.cs
index 44750ae396c..58768d32553 100644
--- a/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Contents/HostedFileContentTests.cs
+++ b/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Contents/HostedFileContentTests.cs
@@ -12,9 +12,9 @@ public class HostedFileContentTests
     [Fact]
     public void Constructor_InvalidInput_Throws()
     {
-        Assert.Throws<ArgumentNullException>(() => new HostedFileContent(null!));
-        Assert.Throws<ArgumentException>(() => new HostedFileContent(string.Empty));
-        Assert.Throws<ArgumentException>(() => new HostedFileContent(" "));
+        Assert.Throws<ArgumentNullException>("fileId", () => new HostedFileContent(null!));
+        Assert.Throws<ArgumentException>("fileId", () => new HostedFileContent(string.Empty));
+        Assert.Throws<ArgumentException>("fileId", () => new HostedFileContent(" "));
     }
 
     [Fact]
@@ -36,9 +36,9 @@ public void Constructor_PropsRoundtrip()
         c.FileId = "id456";
         Assert.Equal("id456", c.FileId);
 
-        Assert.Throws<ArgumentNullException>(() => c.FileId = null!);
-        Assert.Throws<ArgumentException>(() => c.FileId = string.Empty);
-        Assert.Throws<ArgumentException>(() => c.FileId = " ");
+        Assert.Throws<ArgumentNullException>("value", () => c.FileId = null!);
+        Assert.Throws<ArgumentException>("value", () => c.FileId = string.Empty);
+        Assert.Throws<ArgumentException>("value", () => c.FileId = " ");
 
         Assert.Null(c.RawRepresentation);
         object raw = new();
@@ -89,7 +89,7 @@ public void MediaType_Roundtrips()
     public void MediaType_InvalidValue_Throws(string invalidMediaType)
     {
         HostedFileContent c = new("id123");
-        Assert.Throws<ArgumentException>(() => c.MediaType = invalidMediaType);
+        Assert.Throws<ArgumentException>("value", () => c.MediaType = invalidMediaType);
     }
 
     [Theory]
diff --git a/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Contents/HostedVectorStoreContentTests.cs b/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Contents/HostedVectorStoreContentTests.cs
index d709dc3ac87..105d8f2efd9 100644
--- a/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Contents/HostedVectorStoreContentTests.cs
+++ b/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Contents/HostedVectorStoreContentTests.cs
@@ -12,9 +12,9 @@ public class HostedVectorStoreContentTests
     [Fact]
     public void Constructor_InvalidInput_Throws()
     {
-        Assert.Throws<ArgumentNullException>(() => new HostedVectorStoreContent(null!));
-        Assert.Throws<ArgumentException>(() => new HostedVectorStoreContent(string.Empty));
-        Assert.Throws<ArgumentException>(() => new HostedVectorStoreContent(" "));
+        Assert.Throws<ArgumentNullException>("vectorStoreId", () => new HostedVectorStoreContent(null!));
+        Assert.Throws<ArgumentException>("vectorStoreId", () => new HostedVectorStoreContent(string.Empty));
+        Assert.Throws<ArgumentException>("vectorStoreId", () => new HostedVectorStoreContent(" "));
     }
 
     [Fact]
@@ -35,9 +35,9 @@ public void Constructor_PropsRoundtrip()
         c.VectorStoreId = "id456";
         Assert.Equal("id456", c.VectorStoreId);
 
-        Assert.Throws<ArgumentNullException>(() => c.VectorStoreId = null!);
-        Assert.Throws<ArgumentException>(() => c.VectorStoreId = string.Empty);
-        Assert.Throws<ArgumentException>(() => c.VectorStoreId = " ");
+        Assert.Throws<ArgumentNullException>("value", () => c.VectorStoreId = null!);
+        Assert.Throws<ArgumentException>("value", () => c.VectorStoreId = string.Empty);
+        Assert.Throws<ArgumentException>("value", () => c.VectorStoreId = " ");
         Assert.Equal("id456", c.VectorStoreId);
 
         Assert.Null(c.RawRepresentation);
diff --git a/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Utilities/AIJsonSchemaTransformCacheTests.cs b/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Utilities/AIJsonSchemaTransformCacheTests.cs
index 4233e5cdbe1..8f514f7a15e 100644
--- a/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Utilities/AIJsonSchemaTransformCacheTests.cs
+++ b/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Utilities/AIJsonSchemaTransformCacheTests.cs
@@ -12,13 +12,13 @@ public static class AIJsonSchemaTransformCacheTests
     [Fact]
     public static void NullOptions_ThrowsArgumentNullException()
     {
-        Assert.Throws<ArgumentNullException>(() => new AIJsonSchemaTransformCache(transformOptions: null!));
+        Assert.Throws<ArgumentNullException>("transformOptions", () => new AIJsonSchemaTransformCache(transformOptions: null!));
     }
 
     [Fact]
     public static void EmptyOptions_ThrowsArgumentException()
     {
-        Assert.Throws<ArgumentException>(() => new AIJsonSchemaTransformCache(transformOptions: new()));
+        Assert.Throws<ArgumentException>("transformOptions", () => new AIJsonSchemaTransformCache(transformOptions: new()));
     }
 
     [Fact]
@@ -33,14 +33,14 @@ public static void TransformOptions_ReturnsExpectedValue()
     public static void NullFunction_ThrowsArgumentNullException()
     {
         AIJsonSchemaTransformCache cache = new(new() { ConvertBooleanSchemas = true });
-        Assert.Throws<ArgumentNullException>(() => cache.GetOrCreateTransformedSchema(function: null!));
+        Assert.Throws<ArgumentNullException>("function", () => cache.GetOrCreateTransformedSchema(function: null!));
     }
 
     [Fact]
     public static void NullResponseFormat_ThrowsArgumentNullException()
     {
         AIJsonSchemaTransformCache cache = new(new() { ConvertBooleanSchemas = true });
-        Assert.Throws<ArgumentNullException>(() => cache.GetOrCreateTransformedSchema(responseFormat: null!));
+        Assert.Throws<ArgumentNullException>("responseFormat", () => cache.GetOrCreateTransformedSchema(responseFormat: null!));
     }
 
     [Fact]
diff --git a/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Utilities/AIJsonUtilitiesTests.cs b/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Utilities/AIJsonUtilitiesTests.cs
index cb61fcf7086..f27b35e847c 100644
--- a/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Utilities/AIJsonUtilitiesTests.cs
+++ b/test/Libraries/Microsoft.Extensions.AI.Abstractions.Tests/Utilities/AIJsonUtilitiesTests.cs
@@ -1074,8 +1074,8 @@ public static void AddAIContentType_NonAIContent_ThrowsArgumentException()
     public static void AddAIContentType_BuiltInAIContent_ThrowsArgumentException()
     {
         JsonSerializerOptions options = new();
-        Assert.Throws<ArgumentException>(() => options.AddAIContentType<AIContent>("discriminator"));
-        Assert.Throws<ArgumentException>(() => options.AddAIContentType<TextContent>("discriminator"));
+        Assert.Throws<ArgumentException>("contentType", () => options.AddAIContentType<AIContent>("discriminator"));
+        Assert.Throws<ArgumentException>("contentType", () => options.AddAIContentType<TextContent>("discriminator"));
     }
 
     [Fact]
@@ -1398,8 +1398,8 @@ public static void TransformJsonSchema_ValidateWithTestData(ITestData testData)
     public static void TransformJsonSchema_InvalidOptions_ThrowsArgumentException()
     {
         JsonElement schema = JsonDocument.Parse("{}").RootElement;
-        Assert.Throws<ArgumentNullException>(() => AIJsonUtilities.TransformSchema(schema, transformOptions: null!));
-        Assert.Throws<ArgumentException>(() => AIJsonUtilities.TransformSchema(schema, transformOptions: new()));
+        Assert.Throws<ArgumentNullException>("transformOptions", () => AIJsonUtilities.TransformSchema(schema, transformOptions: null!));
+        Assert.Throws<ArgumentException>("transformOptions", () => AIJsonUtilities.TransformSchema(schema, transformOptions: new()));
     }
 
     [Theory]
@@ -1412,7 +1412,7 @@ public static void TransformJsonSchema_InvalidInput_ThrowsArgumentException(stri
     {
         JsonElement schema = JsonDocument.Parse(invalidSchema).RootElement;
         AIJsonSchemaTransformOptions transformOptions = new() { ConvertBooleanSchemas = true };
-        Assert.Throws<ArgumentException>(() => AIJsonUtilities.TransformSchema(schema, transformOptions));
+        Assert.Throws<ArgumentException>("schema", () => AIJsonUtilities.TransformSchema(schema, transformOptions));
     }
 
     private class DerivedAIContent : AIContent
diff --git a/test/Libraries/Microsoft.Extensions.AI.Evaluation.NLP.Tests/NGramTests.cs b/test/Libraries/Microsoft.Extensions.AI.Evaluation.NLP.Tests/NGramTests.cs
index 6c0aefbb02a..f6401cabe08 100644
--- a/test/Libraries/Microsoft.Extensions.AI.Evaluation.NLP.Tests/NGramTests.cs
+++ b/test/Libraries/Microsoft.Extensions.AI.Evaluation.NLP.Tests/NGramTests.cs
@@ -21,7 +21,7 @@ public void Constructor_ValuesAndLength()
     [Fact]
     public void Constructor_ThrowsOnEmpty()
     {
-        Assert.Throws<ArgumentOutOfRangeException>(() => new NGram<int>(Array.Empty<int>()));
+        Assert.Throws<ArgumentOutOfRangeException>("values", () => new NGram<int>(Array.Empty<int>()));
     }
 
     [Fact]
@@ -61,7 +61,7 @@ public void NGramBuilder_Create_Works()
     [Fact]
     public void CreateNGrams()
     {
-        Assert.Throws<ArgumentOutOfRangeException>(() => new int[0].CreateNGrams(-1).ToList());
+        Assert.Throws<ArgumentOutOfRangeException>("n", () => new int[0].CreateNGrams(-1).ToList());
 
         ReadOnlySpan<int> data = [1, 2, 3];
 
@@ -81,11 +81,11 @@ public void CreateNGrams()
     [Fact]
     public void CreateAllNGrams()
     {
-        Assert.Throws<ArgumentOutOfRangeException>(() => new int[0].CreateAllNGrams(-1).ToList());
+        Assert.Throws<ArgumentOutOfRangeException>("minN", () => new int[0].CreateAllNGrams(-1).ToList());
 
-        Assert.Throws<ArgumentOutOfRangeException>(() => new int[0].CreateAllNGrams(0).ToList());
+        Assert.Throws<ArgumentOutOfRangeException>("minN", () => new int[0].CreateAllNGrams(0).ToList());
 
-        Assert.Throws<ArgumentOutOfRangeException>(() => new int[0].CreateAllNGrams(1, 0).ToList());
+        Assert.Throws<ArgumentOutOfRangeException>("maxN", () => new int[0].CreateAllNGrams(1, 0).ToList());
 
         ReadOnlySpan<int> arr = [1, 2, 3];
 
diff --git a/test/Libraries/Microsoft.Extensions.AI.Integration.Tests/ToolReductionTests.cs b/test/Libraries/Microsoft.Extensions.AI.Integration.Tests/ToolReductionTests.cs
index 02a045d9308..436d657acfa 100644
--- a/test/Libraries/Microsoft.Extensions.AI.Integration.Tests/ToolReductionTests.cs
+++ b/test/Libraries/Microsoft.Extensions.AI.Integration.Tests/ToolReductionTests.cs
@@ -16,7 +16,7 @@ public class ToolReductionTests
     public void EmbeddingToolReductionStrategy_Constructor_ThrowsWhenToolLimitIsLessThanOrEqualToZero()
     {
         using var gen = new DeterministicTestEmbeddingGenerator();
-        Assert.Throws<ArgumentOutOfRangeException>(() => new EmbeddingToolReductionStrategy(gen, toolLimit: 0));
+        Assert.Throws<ArgumentOutOfRangeException>("toolLimit", () => new EmbeddingToolReductionStrategy(gen, toolLimit: 0));
     }
 
     [Fact]
diff --git a/test/Libraries/Microsoft.Extensions.AI.Tests/ChatReduction/MessageCountingChatReducerTests.cs b/test/Libraries/Microsoft.Extensions.AI.Tests/ChatReduction/MessageCountingChatReducerTests.cs
index 000f4889bf3..b2b74c711d7 100644
--- a/test/Libraries/Microsoft.Extensions.AI.Tests/ChatReduction/MessageCountingChatReducerTests.cs
+++ b/test/Libraries/Microsoft.Extensions.AI.Tests/ChatReduction/MessageCountingChatReducerTests.cs
@@ -18,7 +18,7 @@ public class MessageCountingChatReducerTests
     [InlineData(-10)]
     public void Constructor_ThrowsOnInvalidTargetCount(int targetCount)
     {
-        Assert.Throws<ArgumentOutOfRangeException>(() => new MessageCountingChatReducer(targetCount));
+        Assert.Throws<ArgumentOutOfRangeException>(nameof(targetCount), () => new MessageCountingChatReducer(targetCount));
     }
 
     [Fact]
@@ -126,8 +126,8 @@ public async Task ReduceAsync_IgnoresFunctionCallsAndResults()
         [
             new ChatMessage(ChatRole.User, "What's the weather?"),
             new ChatMessage(ChatRole.Assistant, [new FunctionCallContent("call1", "get_weather", new Dictionary<string, object?> { ["location"] = "Seattle" })]),
-            new ChatMessage(ChatRole.Tool, [new FunctionResultContent("call1", "Sunny, 72°F")]),
-            new ChatMessage(ChatRole.Assistant, "The weather in Seattle is sunny and 72°F."),
+            new ChatMessage(ChatRole.Tool, [new FunctionResultContent("call1", "Sunny, 72°F")]),
+            new ChatMessage(ChatRole.Assistant, "The weather in Seattle is sunny and 72°F."),
             new ChatMessage(ChatRole.User, "Thanks!"),
             new ChatMessage(ChatRole.Assistant, "You're welcome!"),
         ];
diff --git a/test/Libraries/Microsoft.Extensions.AI.Tests/ChatReduction/SummarizingChatReducerTests.cs b/test/Libraries/Microsoft.Extensions.AI.Tests/ChatReduction/SummarizingChatReducerTests.cs
index 8d5901996aa..8fa801c4811 100644
--- a/test/Libraries/Microsoft.Extensions.AI.Tests/ChatReduction/SummarizingChatReducerTests.cs
+++ b/test/Libraries/Microsoft.Extensions.AI.Tests/ChatReduction/SummarizingChatReducerTests.cs
@@ -17,7 +17,7 @@ public class SummarizingChatReducerTests
     [Fact]
     public void Constructor_ThrowsOnNullChatClient()
     {
-        Assert.Throws<ArgumentNullException>(() => new SummarizingChatReducer(null!, targetCount: 5, threshold: 2));
+        Assert.Throws<ArgumentNullException>("chatClient", () => new SummarizingChatReducer(null!, targetCount: 5, threshold: 2));
     }
 
     [Theory]
@@ -27,7 +27,7 @@ public void Constructor_ThrowsOnNullChatClient()
     public void Constructor_ThrowsOnInvalidTargetCount(int targetCount)
     {
         using var chatClient = new TestChatClient();
-        Assert.Throws<ArgumentOutOfRangeException>(() => new SummarizingChatReducer(chatClient, targetCount, threshold: 2));
+        Assert.Throws<ArgumentOutOfRangeException>(nameof(targetCount), () => new SummarizingChatReducer(chatClient, targetCount, threshold: 2));
     }
 
     [Theory]
@@ -36,7 +36,7 @@ public void Constructor_ThrowsOnInvalidTargetCount(int targetCount)
     public void Constructor_ThrowsOnInvalidThresholdCount(int thresholdCount)
     {
         using var chatClient = new TestChatClient();
-        Assert.Throws<ArgumentOutOfRangeException>(() => new SummarizingChatReducer(chatClient, targetCount: 5, thresholdCount));
+        Assert.Throws<ArgumentOutOfRangeException>("threshold", () => new SummarizingChatReducer(chatClient, targetCount: 5, thresholdCount));
     }
 
     [Fact]