diff --git a/src/AnthropicClient/Utils/JsonSchemaGenerator.cs b/src/AnthropicClient/Utils/JsonSchemaGenerator.cs
index f5101e3..abd23a7 100644
--- a/src/AnthropicClient/Utils/JsonSchemaGenerator.cs
+++ b/src/AnthropicClient/Utils/JsonSchemaGenerator.cs
@@ -180,7 +180,7 @@ static class JsonSchemaGenerator
       // 3. Required
       // 4. Default values
       // 5. Possible values
-      var memberPropertyName = memberType.Name;
+      var memberPropertyName = member.Name;
       var memberDescription = string.Empty;
       var memberRequired = Nullable.GetUnderlyingType(memberType) is null;
 
diff --git a/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTestData.cs b/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTestData.cs
index dd0f89f..b4ee0b2 100644
--- a/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTestData.cs
+++ b/tests/AnthropicClient.Tests/Unit/Utils/JsonSchemaGeneratorTestData.cs
@@ -462,12 +462,12 @@ public class JsonSchemaGeneratorTestData : IEnumerable<object[]>
             ["type"] = "object",
             ["properties"] = new JsonObject()
             {
-              ["String"] = new JsonObject()
+              ["Name"] = new JsonObject()
               {
                 ["type"] = "string",
                 ["description"] = string.Empty
               },
-              ["Int32"] = new JsonObject()
+              ["Age"] = new JsonObject()
               {
                 ["type"] = "integer",
                 ["description"] = string.Empty
@@ -475,8 +475,8 @@ public class JsonSchemaGeneratorTestData : IEnumerable<object[]>
             },
             ["required"] = new JsonArray()
             {
-              "String",
-              "Int32"
+              "Name",
+              "Age"
             }
           }
         },