diff --git a/src/tool_utils.py b/src/tool_utils.py
index bb60a1095..8255bc0a9 100644
--- a/src/tool_utils.py
+++ b/src/tool_utils.py
@@ -54,6 +54,8 @@ def _parse_tool_args(content):
     if isinstance(content, str):
         try:
             args = json.loads(content) if content.strip() else {}
+            if not isinstance(args, dict):
+                args = {}
         except (json.JSONDecodeError, TypeError) as e:
             raise ValueError(str(e))
     elif isinstance(content, dict):
diff --git a/tests/test_admin_tools_registry.py b/tests/test_admin_tools_registry.py
index 4bde9ea9e..0470a0e36 100644
--- a/tests/test_admin_tools_registry.py
+++ b/tests/test_admin_tools_registry.py
@@ -72,3 +72,8 @@ def test_parse_tool_args_lives_in_tool_utils_single_source():
     assert _parse_tool_args('{"action":"add"}') == {"action": "add"}
     # body-envelope unwrap still works
     assert _parse_tool_args('{"body":{"action":"x"}}') == {"action": "x"}
+
+    # non-dict JSON values should return {}
+    assert _parse_tool_args('[1, 2]') == {}
+    assert _parse_tool_args('42') == {}
+    assert _parse_tool_args('"hello"') == {}