diff --git a/src/ClaudeDo.Ui/Services/PtyTerminalSession.cs b/src/ClaudeDo.Ui/Services/PtyTerminalSession.cs
index adf631ee..82980292 100644
--- a/src/ClaudeDo.Ui/Services/PtyTerminalSession.cs
+++ b/src/ClaudeDo.Ui/Services/PtyTerminalSession.cs
@@ -68,6 +68,14 @@ public sealed class PtyTerminalSession : IDisposable
         await WaitForLaunchGateAsync(s_launchGate, s_launchGateTimeout, ct);
         try
         {
+            // If ClaudeDo.App itself was started from inside a claude session (e.g. a dev/test
+            // launch), it inherits these markers and every embedded PTY session would otherwise
+            // inherit them too — the child claude then thinks it's a spawned subagent and
+            // disables transcript saving / degrades its own startup banner. Every ConPTY tile
+            // must look like a fresh top-level session regardless of how ClaudeDo.App was launched.
+            Environment.SetEnvironmentVariable("CLAUDE_CODE_CHILD_SESSION", null);
+            Environment.SetEnvironmentVariable("CLAUDECODE", null);
+
             foreach (var (key, value) in descriptor.Env)
                 Environment.SetEnvironmentVariable(key, value);