diff --git a/src/Linq2GraphQL.Client/ArgumentValue.cs b/src/Linq2GraphQL.Client/ArgumentValue.cs
index f7b5151..9c01eed 100644
--- a/src/Linq2GraphQL.Client/ArgumentValue.cs
+++ b/src/Linq2GraphQL.Client/ArgumentValue.cs
@@ -1,6 +1,6 @@
 namespace Linq2GraphQL.Client;
 
-public class ArgumentValue
+public record ArgumentValue
 {
     public ArgumentValue(string graphName, string graphType, object value)
     {
@@ -10,8 +10,8 @@ public ArgumentValue(string graphName, string graphType, object value)
         VariableName = graphName;
     }
 
-    public string GraphName { get; set; }
-    public string GraphType { get; set; }
-    public object Value { get; set; }
-    public string VariableName { get; set; }
+    public string GraphName { get; init; }
+    public string GraphType { get; init; }
+    public object Value { get; init; }
+    public string VariableName { get; set; } // mutable: unique suffix appended during query building
 }
\ No newline at end of file
diff --git a/src/Linq2GraphQL.Client/GraphQLRequest.cs b/src/Linq2GraphQL.Client/GraphQLRequest.cs
index b60f063..9835454 100644
--- a/src/Linq2GraphQL.Client/GraphQLRequest.cs
+++ b/src/Linq2GraphQL.Client/GraphQLRequest.cs
@@ -2,9 +2,9 @@
 
 namespace Linq2GraphQL.Client;
 
-public class GraphQLRequest
+public record GraphQLRequest
 {
-    [JsonPropertyName("query")] public string Query { get; set; }
+    [JsonPropertyName("query")] public string Query { get; init; }
 
-    [JsonPropertyName("variables")] public Dictionary<string, object> Variables { get; set; }
+    [JsonPropertyName("variables")] public Dictionary<string, object> Variables { get; init; }
 }
\ No newline at end of file