diff --git a/python/composio/tools/base/runtime.py b/python/composio/tools/base/runtime.py
index 88b36c5c43..53aea634a1 100644
--- a/python/composio/tools/base/runtime.py
+++ b/python/composio/tools/base/runtime.py
@@ -262,7 +262,7 @@ def _get_auth_params(app: str, entity_id: str) -> t.Optional[t.Dict]:
         return None
 
 
-def _build_executable_from_args(
+def _build_executable_from_args(  # pylint: disable=too-many-statements
     f: t.Callable,
     app: str,
 ) -> t.Tuple[t.Callable, t.Type[BaseModel], t.Type[BaseModel], bool,]:
@@ -291,6 +291,11 @@ def _build_executable_from_args(
     }
     shell_argument = None
     auth_params = False
+    if "return" not in argspec.annotations:
+        raise InvalidRuntimeAction(
+            f"Please add return type on runtime action `{f.__name__}`"
+        )
+
     for arg, annot in argspec.annotations.items():
         if annot is Shell:
             shell_argument = arg
@@ -323,7 +328,6 @@ def _build_executable_from_args(
                 description = paramdesc[arg]
 
             default = defaults.get(arg, ...)
-
         if arg == "return":
             if returns is not None:
                 arg, _ = returns
diff --git a/python/tests/test_tools/test_base/test_runtime.py b/python/tests/test_tools/test_base/test_runtime.py
index 6019f102fd..5f704cf72a 100644
--- a/python/tests/test_tools/test_base/test_runtime.py
+++ b/python/tests/test_tools/test_base/test_runtime.py
@@ -113,6 +113,22 @@ def square(number: int) -> int:
             return number**2
 
 
+def test_missing_return_type() -> None:
+    with pytest.raises(
+        InvalidRuntimeAction,
+        match="Please add return type on runtime action `square`",
+    ):
+
+        @action(toolname="math")
+        def square(number: int):
+            """
+            Calculate square of a number
+
+            :return result: Square of number
+            """
+            return number**2
+
+
 def test_tool_namespace() -> None:
     """Test to make sure two runtime actions can be defined using one tool name."""