diff --git a/src/ClaudeDo.Worker/Planning/WindowsTerminalPlanningLauncher.cs b/src/ClaudeDo.Worker/Planning/WindowsTerminalPlanningLauncher.cs
index a38948c..cb03995 100644
--- a/src/ClaudeDo.Worker/Planning/WindowsTerminalPlanningLauncher.cs
+++ b/src/ClaudeDo.Worker/Planning/WindowsTerminalPlanningLauncher.cs
@@ -3,6 +3,8 @@
 //   Allowed-tools:     --allowedTools (camelCase), comma-separated tokens
 //   System prompt:     --append-system-prompt-file <path>  (file form)
 //   Session ID:        no pre-assign flag; resume with --resume <id>
+// Launch model: wt.exe directly spawns claude.exe via argv (UseShellExecute=false).
+// No cmd /k shim — arbitrary initial-prompt content would be re-parsed by cmd.exe otherwise.
 
 using System.Diagnostics;
 
@@ -38,29 +40,31 @@ public sealed class WindowsTerminalPlanningLauncher : IPlanningTerminalLauncher
         if (resolvedClaude is null)
             throw new PlanningLaunchException($"claude executable not found: {_claudePath}");
 
-        var initialPrompt = File.Exists(ctx.Files.InitialPromptPath)
-            ? File.ReadAllText(ctx.Files.InitialPromptPath)
-            : string.Empty;
-
-        // Build cmd line: set MAX_THINKING_TOKENS=20000 && claude <args> "prompt"
-        // UseShellExecute=true means we cannot set psi.Environment, so we inject via cmd /k.
-        var claudeArgs = BuildStartArgs(ctx, initialPrompt, resolvedClaude);
-        var cmdLine = $"set MAX_THINKING_TOKENS=20000 && {claudeArgs}";
-
         var psi = new ProcessStartInfo
         {
             FileName = resolvedWt,
-            UseShellExecute = true,
-            WorkingDirectory = ctx.WorkingDir,
+            UseShellExecute = false,
+            CreateNoWindow = false,
         };
-        // wt.exe -d <workingDir> cmd /k "<cmdLine>"
+
+        psi.Environment["MAX_THINKING_TOKENS"] = "20000";
+
         psi.ArgumentList.Add("-d");
         psi.ArgumentList.Add(ctx.WorkingDir);
-        psi.ArgumentList.Add("cmd");
-        psi.ArgumentList.Add("/k");
-        psi.ArgumentList.Add(cmdLine);
+        psi.ArgumentList.Add(resolvedClaude);
+        psi.ArgumentList.Add("--model");
+        psi.ArgumentList.Add(Model);
+        psi.ArgumentList.Add("--mcp-config");
+        psi.ArgumentList.Add(ctx.Files.McpConfigPath);
+        psi.ArgumentList.Add("--append-system-prompt-file");
+        psi.ArgumentList.Add(ctx.Files.SystemPromptPath);
+        psi.ArgumentList.Add("--allowedTools");
+        psi.ArgumentList.Add(AllowedTools);
+        psi.ArgumentList.Add(File.ReadAllText(ctx.Files.InitialPromptPath));
+
+        var proc = Process.Start(psi)
+            ?? throw new PlanningLaunchException("Failed to start Windows Terminal process.");
 
-        Process.Start(psi);
         return Task.CompletedTask;
     }
 
@@ -69,9 +73,6 @@ public sealed class WindowsTerminalPlanningLauncher : IPlanningTerminalLauncher
         if (!Directory.Exists(ctx.WorkingDir))
             throw new PlanningLaunchException($"Working directory does not exist: {ctx.WorkingDir}");
 
-        if (!File.Exists(ctx.McpConfigPath))
-            throw new PlanningLaunchException($"MCP config file not found: {ctx.McpConfigPath}");
-
         var resolvedWt = Resolve(_wtPath);
         if (resolvedWt is null)
             throw new PlanningLaunchException($"Windows Terminal not found: {_wtPath}");
@@ -83,32 +84,24 @@ public sealed class WindowsTerminalPlanningLauncher : IPlanningTerminalLauncher
         var psi = new ProcessStartInfo
         {
             FileName = resolvedWt,
-            UseShellExecute = true,
-            WorkingDirectory = ctx.WorkingDir,
+            UseShellExecute = false,
+            CreateNoWindow = false,
         };
+
         psi.ArgumentList.Add("-d");
         psi.ArgumentList.Add(ctx.WorkingDir);
-        psi.ArgumentList.Add("cmd");
-        psi.ArgumentList.Add("/k");
-        psi.ArgumentList.Add(BuildResumeArgs(ctx, resolvedClaude));
+        psi.ArgumentList.Add(resolvedClaude);
+        psi.ArgumentList.Add("--resume");
+        psi.ArgumentList.Add(ctx.ClaudeSessionId);
+        psi.ArgumentList.Add("--mcp-config");
+        psi.ArgumentList.Add(ctx.McpConfigPath);
+
+        var proc = Process.Start(psi)
+            ?? throw new PlanningLaunchException("Failed to start Windows Terminal process.");
 
-        Process.Start(psi);
         return Task.CompletedTask;
     }
 
-    private static string BuildStartArgs(PlanningSessionStartContext ctx, string initialPrompt, string claudePath)
-    {
-        // Build as a flat string for cmd /k; quote paths that may contain spaces.
-        return $"\"{claudePath}\" --mcp-config \"{ctx.Files.McpConfigPath}\" --append-system-prompt-file \"{ctx.Files.SystemPromptPath}\" --allowedTools \"{AllowedTools}\" --model {Model} \"{EscapeArg(initialPrompt)}\"";
-    }
-
-    private static string BuildResumeArgs(PlanningSessionResumeContext ctx, string claudePath)
-    {
-        return $"\"{claudePath}\" --resume {ctx.ClaudeSessionId} --mcp-config \"{ctx.McpConfigPath}\"";
-    }
-
-    private static string EscapeArg(string value) => value.Replace("\"", "\\\"");
-
     private static string? Resolve(string pathOrName)
     {
         if (File.Exists(pathOrName))