Fix Claude Code Registration and HTTP Transport Issues

MCPForUnity/Editor/Clients/McpClientConfiguratorBase.cs

@@ -334,7 +334,24 @@ public ClaudeCliMcpConfigurator(McpClient client) : base(client) { }
 
         public override string GetConfigPath() => "Managed via Claude CLI";
 
+        /// <summary>
+        /// Checks the Claude CLI registration status.
+        /// MUST be called from the main Unity thread due to EditorPrefs and Application.dataPath access.
+        /// </summary>
         public override McpStatus CheckStatus(bool attemptAutoRewrite = true)
+        {
+            // Capture main-thread-only values before delegating to thread-safe method
+            string projectDir = Path.GetDirectoryName(Application.dataPath);
+            bool useHttpTransport = EditorPrefs.GetBool(EditorPrefKeys.UseHttpTransport, true);
+            return CheckStatusWithProjectDir(projectDir, useHttpTransport, attemptAutoRewrite);
+        }
+
+        /// <summary>
+        /// Internal thread-safe version of CheckStatus.
+        /// Can be called from background threads because all main-thread-only values are passed as parameters.
+        /// Both projectDir and useHttpTransport are REQUIRED (non-nullable) to enforce thread safety at compile time.
+        /// </summary>
+        internal McpStatus CheckStatusWithProjectDir(string projectDir, bool useHttpTransport, bool attemptAutoRewrite = true)
         {
             try
             {
@@ -347,8 +364,11 @@ public override McpStatus CheckStatus(bool attemptAutoRewrite = true)
                     return client.status;
                 }
 
-                string args = "mcp list";
-                string projectDir = Path.GetDirectoryName(Application.dataPath);
+                // projectDir is required - no fallback to Application.dataPath
+                if (string.IsNullOrEmpty(projectDir))
+                {
+                    throw new ArgumentNullException(nameof(projectDir), "Project directory must be provided for thread-safe execution");
+                }
 
                 string pathPrepend = null;
                 if (Application.platform == RuntimePlatform.OSXEditor)
@@ -372,10 +392,35 @@ public override McpStatus CheckStatus(bool attemptAutoRewrite = true)
                 }
                 catch { }
 
-                if (ExecPath.TryRun(claudePath, args, projectDir, out var stdout, out _, 10000, pathPrepend))
+                // Check if UnityMCP exists
+                if (ExecPath.TryRun(claudePath, "mcp list", projectDir, out var listStdout, out var listStderr, 10000, pathPrepend))
                 {
-                    if (!string.IsNullOrEmpty(stdout) && stdout.IndexOf("UnityMCP", StringComparison.OrdinalIgnoreCase) >= 0)
+                    if (!string.IsNullOrEmpty(listStdout) && listStdout.IndexOf("UnityMCP", StringComparison.OrdinalIgnoreCase) >= 0)
                     {
+                        // UnityMCP is registered - now verify transport mode matches
+                        // useHttpTransport parameter is required (non-nullable) to ensure thread safety
+                        bool currentUseHttp = useHttpTransport;
+
+                        // Get detailed info about the registration to check transport type
+                        if (ExecPath.TryRun(claudePath, "mcp get UnityMCP", projectDir, out var getStdout, out var getStderr, 7000, pathPrepend))
+                        {
+                            // Parse the output to determine registered transport mode
+                            // The CLI output format contains "Type: http" or "Type: stdio"
+                            bool registeredWithHttp = getStdout.Contains("Type: http", StringComparison.OrdinalIgnoreCase);
+                            bool registeredWithStdio = getStdout.Contains("Type: stdio", StringComparison.OrdinalIgnoreCase);
+
+                            // Check for transport mismatch
+                            if ((currentUseHttp && registeredWithStdio) || (!currentUseHttp && registeredWithHttp))
+                            {
+                                string registeredTransport = registeredWithHttp ? "HTTP" : "stdio";
+                                string currentTransport = currentUseHttp ? "HTTP" : "stdio";
+                                string errorMsg = $"Transport mismatch: Claude Code is registered with {registeredTransport} but current setting is {currentTransport}. Click Configure to re-register.";
+                                client.SetStatus(McpStatus.Error, errorMsg);
+                                McpLog.Warn(errorMsg);
+                                return client.status;
+                            }
+                        }
+
                         client.SetStatus(McpStatus.Configured);
                         return client.status;
                     }
@@ -452,26 +497,29 @@ private void Register()
             }
             catch { }
 
-            bool already = false;
-            if (!ExecPath.TryRun(claudePath, args, projectDir, out var stdout, out var stderr, 15000, pathPrepend))
+            // Check if UnityMCP already exists and remove it first to ensure clean registration
+            // This ensures we always use the current transport mode setting
+            bool serverExists = ExecPath.TryRun(claudePath, "mcp get UnityMCP", projectDir, out _, out _, 7000, pathPrepend);
+            if (serverExists)
             {
-                string combined = ($"{stdout}\n{stderr}") ?? string.Empty;
-                if (combined.IndexOf("already exists", StringComparison.OrdinalIgnoreCase) >= 0)
+                McpLog.Info("Existing UnityMCP registration found - removing to ensure transport mode is up-to-date");
+                if (!ExecPath.TryRun(claudePath, "mcp remove UnityMCP", projectDir, out var removeStdout, out var removeStderr, 10000, pathPrepend))
                 {
-                    already = true;
-                }
-                else
-                {
-                    throw new InvalidOperationException($"Failed to register with Claude Code:\n{stderr}\n{stdout}");
+                    McpLog.Warn($"Failed to remove existing UnityMCP registration: {removeStderr}. Attempting to register anyway...");
                 }
             }
 
-            if (!already)
+            // Now add the registration with the current transport mode
+            if (!ExecPath.TryRun(claudePath, args, projectDir, out var stdout, out var stderr, 15000, pathPrepend))
             {
-                McpLog.Info("Successfully registered with Claude Code.");
+                throw new InvalidOperationException($"Failed to register with Claude Code:\n{stderr}\n{stdout}");
             }
 
-            CheckStatus();
+            McpLog.Info($"Successfully registered with Claude Code using {(useHttpTransport ? "HTTP" : "stdio")} transport.");
+
+            // Set status to Configured immediately after successful registration
+            // The UI will trigger an async verification check separately to avoid blocking
+            client.SetStatus(McpStatus.Configured);
         }
 
         private void Unregister()
@@ -514,7 +562,7 @@ private void Unregister()
             }
 
             client.SetStatus(McpStatus.NotConfigured);
-            CheckStatus();
+            // Status is already set - no need for blocking CheckStatus() call
         }
 
         public override string GetManualSnippet()

MCPForUnity/Editor/Windows/Components/ClientConfig/McpClientConfigSection.cs

@@ -6,6 +6,7 @@
 using System.Runtime.InteropServices;
 using System.Threading.Tasks;
 using MCPForUnity.Editor.Clients;
+using MCPForUnity.Editor.Constants;
 using MCPForUnity.Editor.Helpers;
 using MCPForUnity.Editor.Models;
 using MCPForUnity.Editor.Services;
@@ -288,12 +289,14 @@ private void OnCopyJsonClicked()
             McpLog.Info("Configuration copied to clipboard");
         }
 
-        public void RefreshSelectedClient()
+        public void RefreshSelectedClient(bool forceImmediate = false)
         {
             if (selectedClientIndex >= 0 && selectedClientIndex < configurators.Count)
             {
                 var client = configurators[selectedClientIndex];
-                RefreshClientStatus(client, forceImmediate: true);
+                // Force immediate for non-Claude CLI, or when explicitly requested
+                bool shouldForceImmediate = forceImmediate || client is not ClaudeCliMcpConfigurator;
+                RefreshClientStatus(client, shouldForceImmediate);
                 UpdateManualConfiguration();
                 UpdateClaudeCliPathVisibility();
             }
@@ -318,14 +321,6 @@ private void RefreshClientStatus(IMcpClientConfigurator client, bool forceImmedi
 
         private void RefreshClaudeCliStatus(IMcpClientConfigurator client, bool forceImmediate)
         {
-            if (forceImmediate)
-            {
-                MCPServiceLocator.Client.CheckClientStatus(client, attemptAutoRewrite: false);
-                lastStatusChecks[client] = DateTime.UtcNow;
-                ApplyStatusToUi(client);
-                return;
-            }
-
             bool hasStatus = lastStatusChecks.ContainsKey(client);
             bool needsRefresh = !hasStatus || ShouldRefreshClient(client);
 
@@ -338,14 +333,21 @@ private void RefreshClaudeCliStatus(IMcpClientConfigurator client, bool forceImm
                 ApplyStatusToUi(client);
             }
 
-            if (needsRefresh && !statusRefreshInFlight.Contains(client))
+            if ((forceImmediate || needsRefresh) && !statusRefreshInFlight.Contains(client))
             {
                 statusRefreshInFlight.Add(client);
                 ApplyStatusToUi(client, showChecking: true);
 
+                // Capture main-thread-only values before async task
+                string projectDir = Path.GetDirectoryName(Application.dataPath);
+                bool useHttpTransport = EditorPrefs.GetBool(EditorPrefKeys.UseHttpTransport, true);
+
                 Task.Run(() =>
                 {
-                    MCPServiceLocator.Client.CheckClientStatus(client, attemptAutoRewrite: false);
+                    // This method is only called for Claude CLI configurators, so we can safely cast
+                    // Use thread-safe version with captured main-thread values
+                    var claudeConfigurator = (ClaudeCliMcpConfigurator)client;
+                    claudeConfigurator.CheckStatusWithProjectDir(projectDir, useHttpTransport, attemptAutoRewrite: false);
                 }).ContinueWith(t =>
                 {
                     bool faulted = false;

MCPForUnity/Editor/Windows/Components/Connection/McpConnectionSection.cs

@@ -55,6 +55,7 @@ private enum TransportProtocol
 
         // Events
         public event Action OnManualConfigUpdateRequested;
+        public event Action OnTransportChanged;
 
         public VisualElement Root { get; private set; }
 
@@ -115,6 +116,7 @@ private void RegisterCallbacks()
                 UpdateHttpFieldVisibility();
                 RefreshHttpUi();
                 OnManualConfigUpdateRequested?.Invoke();
+                OnTransportChanged?.Invoke();
                 McpLog.Info($"Transport changed to: {evt.newValue}");
             });
 

MCPForUnity/Editor/Windows/MCPForUnityEditorWindow.cs

@@ -175,6 +175,8 @@ public void CreateGUI()
                 connectionSection = new McpConnectionSection(connectionRoot);
                 connectionSection.OnManualConfigUpdateRequested += () =>
                     clientConfigSection?.UpdateManualConfiguration();
+                connectionSection.OnTransportChanged += () =>
+                    clientConfigSection?.RefreshSelectedClient(forceImmediate: true);
             }
 
             // Load and initialize Client Configuration section