diff --git a/tests/tool_parsers/test_glm47_moe_tool_parser.py b/tests/tool_parsers/test_glm47_moe_tool_parser.py
index 5e5501e4abff..51696c954788 100644
--- a/tests/tool_parsers/test_glm47_moe_tool_parser.py
+++ b/tests/tool_parsers/test_glm47_moe_tool_parser.py
@@ -91,6 +91,12 @@ def test_args_with_newlines(self, glm47_tool_parser, mock_request):
         assert r.tools_called
         assert json.loads(r.tool_calls[0].function.arguments) == {"city": "Beijing"}
 
+    def test_whitespace_preserved_in_arg_values(self, glm47_tool_parser, mock_request):
+        out = "<tool_call>get_weather<arg_key>city</arg_key><arg_value>  Beijing  </arg_value></tool_call>"
+        r = glm47_tool_parser.extract_tool_calls(out, request=mock_request)
+        assert r.tools_called
+        assert json.loads(r.tool_calls[0].function.arguments) == {"city": "  Beijing  "}
+
     def test_content_before(self, glm47_tool_parser, mock_request):
         out = "Checking.<tool_call>get_current_date</tool_call>"
         r = glm47_tool_parser.extract_tool_calls(out, request=mock_request)
diff --git a/tests/tool_parsers/test_glm4_moe_tool_parser.py b/tests/tool_parsers/test_glm4_moe_tool_parser.py
index 9f430b7814fc..c706d0a4c257 100644
--- a/tests/tool_parsers/test_glm4_moe_tool_parser.py
+++ b/tests/tool_parsers/test_glm4_moe_tool_parser.py
@@ -801,6 +801,36 @@ def test_extract_tool_calls_numeric_deserialization(glm4_moe_tool_parser, mock_r
     assert isinstance(args["enabled"], bool)
 
 
+def test_whitespace_preserved_in_arg_values(glm4_moe_tokenizer):
+    """Test that string arguments preserve leading and trailing whitespace."""
+    tools = [
+        ChatCompletionToolsParam(
+            function=FunctionDefinition(
+                name="apply_diff",
+                parameters={
+                    "type": "object",
+                    "properties": {
+                        "s": {"type": "string"},
+                    },
+                    "required": ["s"],
+                },
+            ),
+        ),
+    ]
+    parser = Glm4MoeModelToolParser(glm4_moe_tokenizer, tools=tools)
+    request = ChatCompletionRequest(model=MODEL, messages=[], tools=tools)
+
+    model_output = """<tool_call>apply_diff
+<arg_key>s</arg_key>
+<arg_value>    indented code    </arg_value>
+</tool_call>"""
+
+    extracted_tool_calls = parser.extract_tool_calls(model_output, request=request)
+    args = json.loads(extracted_tool_calls.tool_calls[0].function.arguments)
+
+    assert args["s"] == "    indented code    "
+
+
 def test_zero_argument_tool_call(glm4_moe_tool_parser, mock_request):
     """Regression: zero-argument tool call crash (PR #32321)."""
     model_output = """<tool_call>get_time
diff --git a/vllm/tool_parsers/glm4_moe_tool_parser.py b/vllm/tool_parsers/glm4_moe_tool_parser.py
index ac266ede3f48..64c4beb14357 100644
--- a/vllm/tool_parsers/glm4_moe_tool_parser.py
+++ b/vllm/tool_parsers/glm4_moe_tool_parser.py
@@ -210,9 +210,10 @@ def extract_tool_calls(
                 arg_dct: dict[str, Any] = {}
                 for key, value in pairs:
                     arg_key = key.strip()
-                    arg_val = value.strip()
-                    if not self._is_string_type(tc_name, arg_key, self.tools):
-                        arg_val = self._deserialize(arg_val)
+                    if self._is_string_type(tc_name, arg_key, self.tools):
+                        arg_val = value
+                    else:
+                        arg_val = self._deserialize(value.strip())
                     logger.debug("arg_key = %s, arg_val = %s", arg_key, arg_val)
                     arg_dct[arg_key] = arg_val
                 tool_calls.append(