diff --git a/agent/display.py b/agent/display.py
index 382ca4746..462d2a439 100644
--- a/agent/display.py
+++ b/agent/display.py
@@ -239,7 +239,6 @@ class KawaiiSpinner:
         self.frame_idx = 0
         self.start_time = None
         self.last_line_len = 0
-        self._last_flush_time = 0.0  # Rate-limit flushes for patch_stdout compat
         # Capture stdout NOW, before any redirect_stdout(devnull) from
         # child agents can replace sys.stdout with a black hole.
         self._out = sys.stdout
@@ -253,6 +252,22 @@ class KawaiiSpinner:
         except (ValueError, OSError):
             pass
 
+    def _is_patch_stdout_proxy(self) -> bool:
+        """Return True when stdout is prompt_toolkit's StdoutProxy.
+
+        patch_stdout wraps sys.stdout in a StdoutProxy that queues writes and
+        injects newlines around each flush().  The \\r overwrite never lands on
+        the correct line — each spinner frame ends up on its own line.
+
+        The CLI already drives a TUI widget (_spinner_text) for spinner display,
+        so KawaiiSpinner's \\r-based animation is redundant under StdoutProxy.
+        """
+        out = self._out
+        # StdoutProxy has a 'raw' attribute (bool) that plain file objects lack.
+        if hasattr(out, 'raw') and type(out).__name__ == 'StdoutProxy':
+            return True
+        return False
+
     def _animate(self):
         # When stdout is not a real terminal (e.g. Docker, systemd, pipe),
         # skip the animation entirely — it creates massive log bloat.
@@ -263,6 +278,16 @@ class KawaiiSpinner:
                 time.sleep(0.5)
             return
 
+        # When running inside prompt_toolkit's patch_stdout context the CLI
+        # renders spinner state via a dedicated TUI widget (_spinner_text).
+        # Driving a \r-based animation here too causes visual overdraw: the
+        # StdoutProxy injects newlines around each flush, so every frame lands
+        # on a new line and overwrites the status bar.
+        if self._is_patch_stdout_proxy():
+            while self.running:
+                time.sleep(0.1)
+            return
+
         # Cache skin wings at start (avoid per-frame imports)
         skin = _get_skin()
         wings = skin.get_spinner_wings() if skin else []
@@ -279,18 +304,7 @@ class KawaiiSpinner:
             else:
                 line = f"  {frame} {self.message} ({elapsed:.1f}s)"
             pad = max(self.last_line_len - len(line), 0)
-            # Rate-limit flush() calls to avoid spinner spam under
-            # prompt_toolkit's patch_stdout.  Each flush() pushes a queue
-            # item that may trigger a separate run_in_terminal() call; if
-            # items are processed one-at-a-time the \r overwrite is lost
-            # and every frame appears on its own line.  By flushing at
-            # most every 0.4s we guarantee multiple \r-frames are batched
-            # into a single write, so the terminal collapses them correctly.
-            now = time.time()
-            should_flush = (now - self._last_flush_time) >= 0.4
-            self._write(f"\r{line}{' ' * pad}", end='', flush=should_flush)
-            if should_flush:
-                self._last_flush_time = now
+            self._write(f"\r{line}{' ' * pad}", end='', flush=True)
             self.last_line_len = len(line)
             self.frame_idx += 1
             time.sleep(0.12)