diff --git a/app/MindWork AI Studio/Tools/ERIClient/ERIClientBase.cs b/app/MindWork AI Studio/Tools/ERIClient/ERIClientBase.cs
index 7d8f0cbe8..9b616d85f 100644
--- a/app/MindWork AI Studio/Tools/ERIClient/ERIClientBase.cs	
+++ b/app/MindWork AI Studio/Tools/ERIClient/ERIClientBase.cs	
@@ -9,7 +9,7 @@ public abstract class ERIClientBase(IERIDataSource dataSource) : IDisposable
 {
     protected readonly IERIDataSource DataSource = dataSource;
     
-    internal static readonly JsonSerializerOptions JSON_OPTIONS = new()
+    internal static readonly JsonSerializerOptions JSON_OPTIONS = new JsonSerializerOptions
     {
         WriteIndented = true,
         AllowTrailingCommas = true,
@@ -20,8 +20,9 @@ public abstract class ERIClientBase(IERIDataSource dataSource) : IDisposable
         Converters =
         {
             new JsonStringEnumConverter(JsonNamingPolicy.SnakeCaseUpper),
-        }
-    };
+        },
+        TypeInfoResolver = ERIClientJsonContext.Default,
+    }.AsReadOnly();
     
     protected readonly HttpClient HttpClient = ExternalHttpClientTimeout.CreateHttpClient(new Uri($"{dataSource.Hostname}:{dataSource.Port}"), ExternalHttpTrustPolicy.ALLOW_CUSTOM_ROOTS_WHEN_HOST_WHITELISTED);
     
diff --git a/app/MindWork AI Studio/Tools/ERIClient/ERIClientJsonContext.cs b/app/MindWork AI Studio/Tools/ERIClient/ERIClientJsonContext.cs
new file mode 100644
index 000000000..30db29e2b
--- /dev/null
+++ b/app/MindWork AI Studio/Tools/ERIClient/ERIClientJsonContext.cs	
@@ -0,0 +1,23 @@
+using System.Text.Json.Serialization;
+
+using AIStudio.Tools.ERIClient.DataModel;
+
+namespace AIStudio.Tools.ERIClient;
+
+/// <summary>
+/// The contracts with which System.Text.Json reads and writes the calls to ERI servers, built at compile time.
+/// </summary>
+[JsonSourceGenerationOptions(GenerationMode = JsonSourceGenerationMode.Metadata)]
+
+// The request:
+[JsonSerializable(typeof(RetrievalRequest))]
+
+// The answers:
+[JsonSerializable(typeof(List<AuthScheme>))]
+[JsonSerializable(typeof(AuthResponse))]
+[JsonSerializable(typeof(DataSourceInfo))]
+[JsonSerializable(typeof(List<EmbeddingInfo>))]
+[JsonSerializable(typeof(List<RetrievalInfo>))]
+[JsonSerializable(typeof(List<Context>))]
+[JsonSerializable(typeof(SecurityRequirements))]
+internal sealed partial class ERIClientJsonContext : JsonSerializerContext;
\ No newline at end of file
diff --git a/app/MindWork AI Studio/Tools/ToolCallingSystem/ToolCallingImplementations/WebSearch/WebSearchJson.cs b/app/MindWork AI Studio/Tools/ToolCallingSystem/ToolCallingImplementations/WebSearch/WebSearchJson.cs
index 6ac1d24aa..136c31e8a 100644
--- a/app/MindWork AI Studio/Tools/ToolCallingSystem/ToolCallingImplementations/WebSearch/WebSearchJson.cs	
+++ b/app/MindWork AI Studio/Tools/ToolCallingSystem/ToolCallingImplementations/WebSearch/WebSearchJson.cs	
@@ -14,10 +14,11 @@ namespace AIStudio.Tools.ToolCallingSystem.ToolCallingImplementations.WebSearch;
 /// </remarks>
 internal static class WebSearchJson
 {
-    public static readonly JsonSerializerOptions OPTIONS = new()
+    public static readonly JsonSerializerOptions OPTIONS = new JsonSerializerOptions
     {
         PropertyNamingPolicy = JsonNamingPolicy.SnakeCaseLower,
         PropertyNameCaseInsensitive = true,
         DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull,
-    };
+        TypeInfoResolver = WebSearchJsonContext.Default,
+    }.AsReadOnly();
 }
\ No newline at end of file
diff --git a/app/MindWork AI Studio/Tools/ToolCallingSystem/ToolCallingImplementations/WebSearch/WebSearchJsonContext.cs b/app/MindWork AI Studio/Tools/ToolCallingSystem/ToolCallingImplementations/WebSearch/WebSearchJsonContext.cs
new file mode 100644
index 000000000..8185029af
--- /dev/null
+++ b/app/MindWork AI Studio/Tools/ToolCallingSystem/ToolCallingImplementations/WebSearch/WebSearchJsonContext.cs	
@@ -0,0 +1,21 @@
+using System.Text.Json.Serialization;
+
+using AIStudio.Tools.ToolCallingSystem.ToolCallingImplementations.WebSearch.Staan;
+using AIStudio.Tools.ToolCallingSystem.ToolCallingImplementations.WebSearch.Tavily;
+
+namespace AIStudio.Tools.ToolCallingSystem.ToolCallingImplementations.WebSearch;
+
+/// <summary>
+/// The contracts with which System.Text.Json reads and writes the calls to the search services, built at
+/// compile time.
+/// </summary>
+/// <remarks>
+/// SearXNG is missing on purpose: its answers differ between instances, so its client reads them as a tree
+/// of JSON nodes instead.
+/// </remarks>
+[JsonSourceGenerationOptions(GenerationMode = JsonSourceGenerationMode.Metadata)]
+[JsonSerializable(typeof(StaanSearchRequest))]
+[JsonSerializable(typeof(StaanSearchResponse))]
+[JsonSerializable(typeof(TavilySearchRequest))]
+[JsonSerializable(typeof(TavilySearchResponse))]
+internal sealed partial class WebSearchJsonContext : JsonSerializerContext;
\ No newline at end of file
diff --git a/app/Tests/Serialization/JsonCoverageTests.cs b/app/Tests/Serialization/JsonCoverageTests.cs
index e40776b90..716585793 100644
--- a/app/Tests/Serialization/JsonCoverageTests.cs
+++ b/app/Tests/Serialization/JsonCoverageTests.cs
@@ -18,6 +18,8 @@ public sealed class JsonCoverageTests
     [TestCaseSource(typeof(JsonTestRoots), nameof(JsonTestRoots.ProviderAnswers))]
     [TestCaseSource(typeof(JsonTestRoots), nameof(JsonTestRoots.RuntimeRequests))]
     [TestCaseSource(typeof(JsonTestRoots), nameof(JsonTestRoots.RuntimeAnswers))]
+    [TestCaseSource(typeof(JsonTestRoots), nameof(JsonTestRoots.ServiceRequests))]
+    [TestCaseSource(typeof(JsonTestRoots), nameof(JsonTestRoots.ServiceAnswers))]
     public void EveryContractComesFromSourceGeneration(JsonTestRoot root)
     {
         var typesWithoutGeneratedContract = JsonTypeGraph.Collect(root.Type, root.Options)