diff --git a/src/kimi_cli/utils/string.py b/src/kimi_cli/utils/string.py
index e6fff6f7a..7d4dea807 100644
--- a/src/kimi_cli/utils/string.py
+++ b/src/kimi_cli/utils/string.py
@@ -28,10 +28,13 @@ def shorten(text: str, *, width: int, placeholder: str = "…") -> str:
 
 def shorten_middle(text: str, width: int, remove_newline: bool = True) -> str:
     """Shorten the text by inserting ellipsis in the middle."""
-    if len(text) <= width:
-        return text
+    # Strip newlines first: callers rely on this to keep the result on a single
+    # line, and doing it before the length check ensures short multi-line inputs
+    # are flattened too (and that the check sees the post-flattening length).
     if remove_newline:
         text = _NEWLINE_RE.sub(" ", text)
+    if len(text) <= width:
+        return text
     return text[: width // 2] + "..." + text[-width // 2 :]
 
 
diff --git a/tests/utils/test_shorten.py b/tests/utils/test_shorten.py
index 6b35f7706..380e4a1f6 100644
--- a/tests/utils/test_shorten.py
+++ b/tests/utils/test_shorten.py
@@ -70,3 +70,34 @@ def test_placeholder_longer_than_cut():
     result = shorten("hello", width=1, placeholder="...")
     assert len(result) <= 1
     assert result == "h"
+
+
+def test_shorten_middle_short_text_unchanged():
+    from kimi_cli.utils.string import shorten_middle
+
+    assert shorten_middle("hello", 50) == "hello"
+
+
+def test_shorten_middle_strips_newlines_in_short_text():
+    """remove_newline must apply even when the text is shorter than width."""
+    from kimi_cli.utils.string import shorten_middle
+
+    result = shorten_middle("ls -la\npwd\necho done", 50)
+    assert "\n" not in result
+    assert result == "ls -la pwd echo done"
+
+
+def test_shorten_middle_can_keep_newlines():
+    from kimi_cli.utils.string import shorten_middle
+
+    result = shorten_middle("a\nb", 50, remove_newline=False)
+    assert result == "a\nb"
+
+
+def test_shorten_middle_long_text_gets_ellipsis():
+    from kimi_cli.utils.string import shorten_middle
+
+    text = "x" * 100
+    result = shorten_middle(text, 50)
+    assert "..." in result
+    assert result == "x" * 25 + "..." + "x" * 25