fix(tools): raise ToolUsageError instead of bare raise on non-dict args

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

@@ -849,9 +849,13 @@ def _original_tool_calling(
             return ToolUsageError(f"{I18N_DEFAULT.errors('tool_arguments_error')}")
 
         if not isinstance(arguments, dict):
+            error = ToolUsageError(f"{I18N_DEFAULT.errors('tool_arguments_error')}")
+            # A bare ``raise`` here would fail with "No active exception to
+            # re-raise" (this path is outside the except block above), so raise
+            # the intended ToolUsageError explicitly.
             if raise_error:
-                raise
-            return ToolUsageError(f"{I18N_DEFAULT.errors('tool_arguments_error')}")
+                raise error
+            return error
 
         return ToolCalling(
             tool_name=sanitize_tool_name(tool.name),

lib/crewai/tests/tools/test_tool_usage.py

@@ -25,7 +25,7 @@
 )
 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.tool_utils import execute_tool_and_check_finality
 from pydantic import BaseModel, Field
 import pytest
@@ -261,6 +261,46 @@ def test_last_raw_result_falls_back_only_until_recorded():
     assert tool_usage.get_last_raw_result("formatted result") is None
 
 
+def _tool_usage_for_calling() -> ToolUsage:
+    return ToolUsage(
+        tools_handler=MagicMock(),
+        tools=[],
+        task=MagicMock(),
+        function_calling_llm=MagicMock(),
+        agent=MagicMock(),
+        action=MagicMock(),
+    )
+
+
+def test_original_tool_calling_non_dict_raises_tool_usage_error():
+    """When validated arguments are not a dict and raise_error=True, a
+    ToolUsageError must be raised — not a RuntimeError from a bare `raise`
+    with no active exception (#6430)."""
+    tool_usage = _tool_usage_for_calling()
+
+    with (
+        patch.object(tool_usage, "_select_tool", return_value=MagicMock()),
+        patch.object(tool_usage, "_validate_tool_input", return_value=[1, 2, 3]),
+    ):
+        with pytest.raises(ToolUsageError):
+            tool_usage._original_tool_calling("some tool string", raise_error=True)
+
+
+def test_original_tool_calling_non_dict_returns_error_when_not_raising():
+    """With raise_error=False, non-dict arguments return a ToolUsageError."""
+    tool_usage = _tool_usage_for_calling()
+
+    with (
+        patch.object(tool_usage, "_select_tool", return_value=MagicMock()),
+        patch.object(tool_usage, "_validate_tool_input", return_value=[1, 2, 3]),
+    ):
+        result = tool_usage._original_tool_calling(
+            "some tool string", raise_error=False
+        )
+
+    assert isinstance(result, ToolUsageError)
+
+
 def test_validate_tool_input_booleans_and_none():
     tool_usage = ToolUsage(
         tools_handler=MagicMock(),