Hide experimental types from external source generators using internal property pattern (#1301)

src/ModelContextProtocol.Core/Protocol/CallToolRequestParams.cs

@@ -1,3 +1,4 @@
+using System.Diagnostics.CodeAnalysis;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 
@@ -33,6 +34,16 @@ public sealed class CallToolRequestParams : RequestParams
     /// When present, indicates that the requestor wants this operation executed as a task.
     /// The receiver must support task augmentation for this specific request type.
     /// </remarks>
+    [Experimental(Experimentals.Tasks_DiagnosticId, UrlFormat = Experimentals.Tasks_Url)]
+    [JsonIgnore]
+    public McpTaskMetadata? Task
+    {
+        get => TaskCore;
+        set => TaskCore = value;
+    }
+
+    // See ExperimentalInternalPropertyTests.cs before modifying this property.
+    [JsonInclude]
     [JsonPropertyName("task")]
-    public McpTaskMetadata? Task { get; set; }
+    internal McpTaskMetadata? TaskCore { get; set; }
 }

src/ModelContextProtocol.Core/Protocol/CallToolResult.cs

@@ -1,3 +1,4 @@
+using System.Diagnostics.CodeAnalysis;
 using System.Text.Json.Nodes;
 using System.Text.Json.Serialization;
 
@@ -72,6 +73,16 @@ public sealed class CallToolResult : Result
     /// (<see cref="Content"/>, <see cref="StructuredContent"/>, <see cref="IsError"/>) may not be populated.
     /// The actual tool result can be retrieved later via <c>tasks/result</c>.
     /// </remarks>
+    [Experimental(Experimentals.Tasks_DiagnosticId, UrlFormat = Experimentals.Tasks_Url)]
+    [JsonIgnore]
+    public McpTask? Task
+    {
+        get => TaskCore;
+        set => TaskCore = value;
+    }
+
+    // See ExperimentalInternalPropertyTests.cs before modifying this property.
+    [JsonInclude]
     [JsonPropertyName("task")]
-    public McpTask? Task { get; set; }
+    internal McpTask? TaskCore { get; set; }
 }

src/ModelContextProtocol.Core/Protocol/ClientCapabilities.cs

@@ -1,4 +1,5 @@
 using System.ComponentModel;
+using System.Diagnostics.CodeAnalysis;
 using System.Text.Json.Serialization;
 using ModelContextProtocol.Client;
 using ModelContextProtocol.Server;
@@ -80,6 +81,16 @@ public sealed class ClientCapabilities
     /// See <see cref="McpTasksCapability"/> for details on configuring which operations support tasks.
     /// </para>
     /// </remarks>
+    [Experimental(Experimentals.Tasks_DiagnosticId, UrlFormat = Experimentals.Tasks_Url)]
+    [JsonIgnore]
+    public McpTasksCapability? Tasks
+    {
+        get => TasksCore;
+        set => TasksCore = value;
+    }
+
+    // See ExperimentalInternalPropertyTests.cs before modifying this property.
+    [JsonInclude]
     [JsonPropertyName("tasks")]
-    public McpTasksCapability? Tasks { get; set; }
+    internal McpTasksCapability? TasksCore { get; set; }
 }

src/ModelContextProtocol.Core/Protocol/CreateMessageRequestParams.cs

@@ -1,3 +1,4 @@
+using System.Diagnostics.CodeAnalysis;
 using System.Text.Json;
 using System.Text.Json.Serialization;
 
@@ -160,6 +161,16 @@ public sealed class CreateMessageRequestParams : RequestParams
     /// When present, indicates that the requestor wants this operation executed as a task.
     /// The receiver must support task augmentation for this specific request type.
     /// </remarks>
+    [Experimental(Experimentals.Tasks_DiagnosticId, UrlFormat = Experimentals.Tasks_Url)]
+    [JsonIgnore]
+    public McpTaskMetadata? Task
+    {
+        get => TaskCore;
+        set => TaskCore = value;
+    }
+
+    // See ExperimentalInternalPropertyTests.cs before modifying this property.
+    [JsonInclude]
     [JsonPropertyName("task")]
-    public McpTaskMetadata? Task { get; set; }
+    internal McpTaskMetadata? TaskCore { get; set; }
 }

src/ModelContextProtocol.Core/Protocol/ElicitRequestParams.cs

@@ -99,8 +99,18 @@ public sealed class ElicitRequestParams : RequestParams
     /// When present, indicates that the requestor wants this operation executed as a task.
     /// The receiver must support task augmentation for this specific request type.
     /// </remarks>
+    [Experimental(Experimentals.Tasks_DiagnosticId, UrlFormat = Experimentals.Tasks_Url)]
+    [JsonIgnore]
+    public McpTaskMetadata? Task
+    {
+        get => TaskCore;
+        set => TaskCore = value;
+    }
+
+    // See ExperimentalInternalPropertyTests.cs before modifying this property.
+    [JsonInclude]
     [JsonPropertyName("task")]
-    public McpTaskMetadata? Task { get; set; }
+    internal McpTaskMetadata? TaskCore { get; set; }
 
     /// <summary>Represents a request schema used in a form mode elicitation request.</summary>
     public sealed class RequestSchema

src/ModelContextProtocol.Core/Protocol/ServerCapabilities.cs

@@ -1,4 +1,5 @@
 using System.ComponentModel;
+using System.Diagnostics.CodeAnalysis;
 using System.Text.Json.Serialization;
 using ModelContextProtocol.Server;
 
@@ -79,6 +80,16 @@ public sealed class ServerCapabilities
     /// See <see cref="McpTasksCapability"/> for details on configuring which operations support tasks.
     /// </para>
     /// </remarks>
+    [Experimental(Experimentals.Tasks_DiagnosticId, UrlFormat = Experimentals.Tasks_Url)]
+    [JsonIgnore]
+    public McpTasksCapability? Tasks
+    {
+        get => TasksCore;
+        set => TasksCore = value;
+    }
+
+    // See ExperimentalInternalPropertyTests.cs before modifying this property.
+    [JsonInclude]
     [JsonPropertyName("tasks")]
-    public McpTasksCapability? Tasks { get; set; }
+    internal McpTasksCapability? TasksCore { get; set; }
 }

src/ModelContextProtocol.Core/Protocol/Tool.cs

@@ -128,8 +128,17 @@ public sealed class Tool : IBaseMetadata
     /// regarding task augmentation support. See <see cref="ToolExecution"/> for details.
     /// </remarks>
     [Experimental(Experimentals.Tasks_DiagnosticId, UrlFormat = Experimentals.Tasks_Url)]
+    [JsonIgnore]
+    public ToolExecution? Execution
+    {
+        get => ExecutionCore;
+        set => ExecutionCore = value;
+    }
+
+    // See ExperimentalInternalPropertyTests.cs before modifying this property.
+    [JsonInclude]
     [JsonPropertyName("execution")]
-    public ToolExecution? Execution { get; set; }
+    internal ToolExecution? ExecutionCore { get; set; }
 
     /// <summary>
     /// Gets or sets an optional list of icons for this tool.