Generated the JSON contracts of providers, the runtime, and services at compile time (#1150)

app/MindWork AI Studio/Provider/OpenAI/ResponsesAPIRequest.cs

@@ -17,11 +17,26 @@ public record ResponsesAPIRequest(
     bool Store,
     IList<object> Tools)
 {
+    //
+    // The properties of the parameters, declared again to be settable. The source generation of System.Text.Json
+    // sets every init-only property while it creates the object, also one missing in the JSON, so its value from
+    // the parameterless constructor would get lost. Keep them first and in the order of the parameters, which is
+    // the order they get written in:
+    //
+    public string Model { get; set; } = Model;
+    public IList<object> Input { get; set; } = Input;
+    public bool Stream { get; set; } = Stream;
+    public bool Store { get; set; } = Store;
+    public IList<object> Tools { get; set; } = Tools;
+
     public ResponsesAPIRequest() : this(string.Empty, [], true, false, [])
     {
     }
-    
-    // Attention: The "required" modifier is not supported for [JsonExtensionData].
+
+    //
+    // Attention: The "required" modifier is not supported for [JsonExtensionData], and neither is init: the source
+    // generation of System.Text.Json refuses to write the request at all then.
+    //
     [JsonExtensionData]
-    public IDictionary<string, object> AdditionalApiParameters { get; init; } = new Dictionary<string, object>();
+    public IDictionary<string, object> AdditionalApiParameters { get; set; } = new Dictionary<string, object>();
 }