From 841e81016783e389b190a0bef03a3a6a53be8b75 Mon Sep 17 00:00:00 2001
From: Copilot <198982749+Copilot@users.noreply.github.com>
Date: Tue, 17 Feb 2026 16:00:12 -0800
Subject: [PATCH] Fix StdioServerTransport.DisposeAsync() hang:
 CancellableStdinStream missing Dispose override (#1276)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: stephentoub <2642209+stephentoub@users.noreply.github.com>
---
 .../Server/StdioServerTransport.cs                     | 10 ++++++++++
 .../Transport/StdioServerTransportTests.cs             |  2 +-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/ModelContextProtocol.Core/Server/StdioServerTransport.cs b/src/ModelContextProtocol.Core/Server/StdioServerTransport.cs
index 307c180..f434263 100644
--- a/src/ModelContextProtocol.Core/Server/StdioServerTransport.cs
+++ b/src/ModelContextProtocol.Core/Server/StdioServerTransport.cs
@@ -59,6 +59,16 @@ public sealed class StdioServerTransport : StreamServerTransport
         }
 #endif
 
+        protected override void Dispose(bool disposing)
+        {
+            if (disposing)
+            {
+                stdinStream.Dispose();
+            }
+
+            base.Dispose(disposing);
+        }
+
         // The McpServer shouldn't call flush on the stdin Stream, but it doesn't need to throw just in case.
         public override void Flush() { }
 
diff --git a/tests/ModelContextProtocol.Tests/Transport/StdioServerTransportTests.cs b/tests/ModelContextProtocol.Tests/Transport/StdioServerTransportTests.cs
index 54a1a96..a993b41 100644
--- a/tests/ModelContextProtocol.Tests/Transport/StdioServerTransportTests.cs
+++ b/tests/ModelContextProtocol.Tests/Transport/StdioServerTransportTests.cs
@@ -24,7 +24,7 @@ public class StdioServerTransportTests : LoggedTest
         };
     }
 
-    [Fact(Skip="https://github.com/modelcontextprotocol/csharp-sdk/issues/143")]
+    [Fact]
     public async Task Constructor_Should_Initialize_With_Valid_Parameters()
     {
         // Act