fix(tools): raise ToolUsageError instead of bare raise in _original_tool_calling

lib/crewai/src/crewai/tools/tool_usage.py

@@ -850,7 +850,7 @@ def _original_tool_calling(
 
         if not isinstance(arguments, dict):
             if raise_error:
-                raise
+                raise ToolUsageError(f"{I18N_DEFAULT.errors('tool_arguments_error')}")
             return ToolUsageError(f"{I18N_DEFAULT.errors('tool_arguments_error')}")
 
         return ToolCalling(

lib/crewai/tests/tools/test_tool_usage.py

@@ -25,7 +25,8 @@
 )
 from crewai.tools import BaseTool
 from crewai.tools.tool_calling import ToolCalling
-from crewai.tools.tool_usage import ToolUsage
+from crewai.tools.tool_usage import ToolUsage, ToolUsageError
+from crewai.utilities.i18n import I18N_DEFAULT
 from crewai.utilities.tool_utils import execute_tool_and_check_finality
 from pydantic import BaseModel, Field
 import pytest
@@ -903,3 +904,26 @@ def on_finished(source, event):
     assert len(finished_events) == 0, (
         "ToolUsageFinishedEvent should NOT be emitted after ToolUsageErrorEvent"
     )
+
+
+def test_original_tool_calling_raises_tool_usage_error_for_non_dict_arguments():
+    """Regression test for #6430: non-dict arguments must raise ToolUsageError,
+    not a bare `raise` (which would raise RuntimeError: No active exception)."""
+    tool_usage = ToolUsage(
+        tools_handler=MagicMock(),
+        tools=[RandomNumberTool()],
+        task=MagicMock(),
+        function_calling_llm=MagicMock(),
+        agent=example_agent,
+        action=MagicMock(tool="Random Number Generator", tool_input="[]"),
+    )
+
+    with patch.object(tool_usage, "_validate_tool_input", return_value=["not", "a", "dict"]):
+        with pytest.raises(ToolUsageError) as e_info:
+            tool_usage._original_tool_calling("irrelevant", raise_error=True)
+
+        assert str(e_info.value) == I18N_DEFAULT.errors("tool_arguments_error")
+
+        result = tool_usage._original_tool_calling("irrelevant", raise_error=False)
+        assert isinstance(result, ToolUsageError)
+        assert str(result) == I18N_DEFAULT.errors("tool_arguments_error")