Refused JSON contracts built by reflection and checked all of them in the trimmed build (#1152)

app/MindWork AI Studio/Tools/ToolCallingSystem/ToolExecutionResult.cs

@@ -21,7 +21,11 @@ public sealed class ToolExecutionResult
     /// with every umlaut as six characters. The relaxed encoder escapes only what JSON requires.
     /// </remarks>
     // Internal, so a tool which keeps its result within a budget measures exactly what the model gets:
-    internal static readonly JsonSerializerOptions MODEL_CONTENT_OPTIONS = new() { Encoder = JavaScriptEncoder.UnsafeRelaxedJsonEscaping };
+    internal static readonly JsonSerializerOptions MODEL_CONTENT_OPTIONS = new JsonSerializerOptions
+    {
+        Encoder = JavaScriptEncoder.UnsafeRelaxedJsonEscaping,
+        TypeInfoResolver = ToolExecutionResultJsonContext.Default,
+    }.AsReadOnly();
 
     public string? TextContent { get; init; }
 

app/MindWork AI Studio/Tools/ToolCallingSystem/ToolExecutionResultJsonContext.cs

@@ -0,0 +1,15 @@
+using System.Text.Json.Nodes;
+using System.Text.Json.Serialization;
+
+namespace AIStudio.Tools.ToolCallingSystem;
+
+/// <summary>
+/// The contracts of the options with which a tool result is written for the model, built at compile time.
+/// </summary>
+/// <remarks>
+/// A JSON result is a tree of JSON nodes, which writes itself and needs no contract from the options. The
+/// context is there all the same, so that these options can never fall back to reflection either.
+/// </remarks>
+[JsonSourceGenerationOptions(GenerationMode = JsonSourceGenerationMode.Metadata)]
+[JsonSerializable(typeof(JsonNode))]
+internal sealed partial class ToolExecutionResultJsonContext : JsonSerializerContext;