diff --git a/python/packages/core/agent_framework/_mcp.py b/python/packages/core/agent_framework/_mcp.py
index d872b2b92d..d4d5d515dd 100644
--- a/python/packages/core/agent_framework/_mcp.py
+++ b/python/packages/core/agent_framework/_mcp.py
@@ -544,7 +544,7 @@ class MCPTool:
     @property
     def functions(self) -> list[FunctionTool]:
         """Get the list of functions that are allowed."""
-        if not self.allowed_tools:
+        if self.allowed_tools is None:
             return self._functions
         allowed_names = set(self.allowed_tools)
         filtered_functions: list[FunctionTool] = []
diff --git a/python/packages/core/tests/core/test_mcp.py b/python/packages/core/tests/core/test_mcp.py
index 519d8e5db3..365c188a35 100644
--- a/python/packages/core/tests/core/test_mcp.py
+++ b/python/packages/core/tests/core/test_mcp.py
@@ -1465,6 +1465,7 @@ def test_mcp_tool_approval_mode_returns_none_for_unmatched_names() -> None:
             3,
             ["tool_one", "tool_two", "tool_three"],
         ),  # None means all tools are allowed
+        ([], 0, []),  # Empty list means no tools are allowed
         (["tool_one"], 1, ["tool_one"]),  # Only tool_one is allowed
         (
             ["tool_one", "tool_three"],