diff --git a/src/AnthropicClient/AnthropicClient.csproj b/src/AnthropicClient/AnthropicClient.csproj
index 17149b5..6e77cb6 100644
--- a/src/AnthropicClient/AnthropicClient.csproj
+++ b/src/AnthropicClient/AnthropicClient.csproj
@@ -35,7 +35,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="8.0.0" />
-    <PackageReference Include="System.Text.Json" Version="8.0.4" />
+    <PackageReference Include="System.Text.Json" Version="8.0.5" />
     <PackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" PrivateAssets="All" />
   </ItemGroup>
 
diff --git a/tests/AnthropicClient.Tests/AnthropicClient.Tests.csproj b/tests/AnthropicClient.Tests/AnthropicClient.Tests.csproj
index c5ad00c..0a5f3db 100644
--- a/tests/AnthropicClient.Tests/AnthropicClient.Tests.csproj
+++ b/tests/AnthropicClient.Tests/AnthropicClient.Tests.csproj
@@ -10,21 +10,21 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="FluentAssertions" Version="6.12.0" />
+    <PackageReference Include="FluentAssertions" Version="6.12.2" />
     <PackageReference Include="Microsoft.Extensions.Configuration" Version="8.0.0" />
     <PackageReference Include="Microsoft.Extensions.Configuration.EnvironmentVariables" Version="8.0.0" />
     <PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="8.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.8.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
     <PackageReference Include="RichardSzalay.MockHttp" Version="7.0.0" />
     <PackageReference Include="System.Linq.Async" Version="6.0.1" />
     <PackageReference Include="SystemTextJson.JsonDiffPatch.Xunit" Version="2.0.0" />
-    <PackageReference Include="xunit" Version="2.5.3" />
-    <PackageReference Include="xunit.runner.visualstudio" Version="2.5.3" />
-    <PackageReference Include="coverlet.collector" Version="6.0.0">
+    <PackageReference Include="xunit" Version="2.9.2" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.8.2" />
+    <PackageReference Include="coverlet.collector" Version="6.0.2">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="coverlet.msbuild" Version="6.0.0">
+    <PackageReference Include="coverlet.msbuild" Version="6.0.2">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
       <PrivateAssets>all</PrivateAssets>
     </PackageReference>
diff --git a/tests/AnthropicClient.Tests/Unit/Models/ToolTests.cs b/tests/AnthropicClient.Tests/Unit/Models/ToolTests.cs
index ba026b6..bf71ca2 100644
--- a/tests/AnthropicClient.Tests/Unit/Models/ToolTests.cs
+++ b/tests/AnthropicClient.Tests/Unit/Models/ToolTests.cs
@@ -8,11 +8,11 @@ public class ToolTests : SerializationTest
   [InlineData(null)]
   [InlineData("")]
   [InlineData(" ")]
-  public void Constructor_WhenGivenInvalidNameValue_ItShouldThrowArgumentException(string name)
+  public void Constructor_WhenGivenInvalidNameValue_ItShouldThrowArgumentException(string? name)
   {
     var method = () => true;
     var function = new AnthropicFunction(method.Method);
-    var action = () => new Tool(name, "description", function);
+    var action = () => new Tool(name!, "description", function);
 
     action.Should().Throw<ArgumentException>();
   }
@@ -21,11 +21,11 @@ public class ToolTests : SerializationTest
   [InlineData(null)]
   [InlineData("")]
   [InlineData(" ")]
-  public void Constructor_WhenGivenInvalidDescriptionValue_ItShouldThrowArgumentException(string description)
+  public void Constructor_WhenGivenInvalidDescriptionValue_ItShouldThrowArgumentException(string? description)
   {
     var method = () => true;
     var function = new AnthropicFunction(method.Method);
-    var action = () => new Tool("name", description, function);
+    var action = () => new Tool("name", description!, function);
 
     action.Should().Throw<ArgumentException>();
   }
@@ -86,9 +86,9 @@ public class ToolTests : SerializationTest
   [InlineData(typeof(TestClass), "")]
   [InlineData(typeof(TestClass), " ")]
   [InlineData(typeof(TestClass), "MadeUpMethod")]
-  public void CreateFromStaticMethod_WhenGivenInvalidMethodName_ItShouldThrowArgumentException(Type type, string methodName)
+  public void CreateFromStaticMethod_WhenGivenInvalidMethodName_ItShouldThrowArgumentException(Type type, string? methodName)
   {
-    var action = () => Tool.CreateFromStaticMethod("name", "description", type, methodName);
+    var action = () => Tool.CreateFromStaticMethod("name", "description", type, methodName!);
 
     action.Should().Throw<ArgumentException>();
   }
@@ -158,9 +158,9 @@ public class ToolTests : SerializationTest
   [InlineData("")]
   [InlineData(" ")]
   [InlineData("MadeUpMethod")]
-  public void CreateFromInstanceMethod_WhenGivenInvalidMethodName_ItShouldThrowArgumentException(string methodName)
+  public void CreateFromInstanceMethod_WhenGivenInvalidMethodName_ItShouldThrowArgumentException(string? methodName)
   {
-    var action = () => Tool.CreateFromInstanceMethod("name", "description", new TestClass(), methodName);
+    var action = () => Tool.CreateFromInstanceMethod("name", "description", new TestClass(), methodName!);
 
     action.Should().Throw<ArgumentException>();
   }