diff --git a/lib/python/picongpu/picmi/diagnostics/auto.py b/lib/python/picongpu/picmi/diagnostics/auto.py
index a8783e8d4c..79b0110803 100644
--- a/lib/python/picongpu/picmi/diagnostics/auto.py
+++ b/lib/python/picongpu/picmi/diagnostics/auto.py
@@ -1,11 +1,13 @@
 """
 This file is part of PIConGPU.
 Copyright 2025 PIConGPU contributors
-Authors: Pawel Ordyna
+Authors: Pawel Ordyna, Masoud Afshari
 License: GPLv3+
 """
 
 import typeguard
+from typing import Union
+
 
 from ...pypicongpu.output.auto import Auto as PyPIConGPUAuto
 from ..copy_attributes import default_converts_to
@@ -20,13 +22,22 @@ class Auto:
 
     Parameters
     ----------
-    period: int
+    period: int or TimeStepSpec
         Number of simulation steps between consecutive outputs.
         Unit: steps (simulation time steps).
     """
 
-    period: TimeStepSpec
-    """Number of simulation steps between consecutive outputs. Unit: steps (simulation time steps)."""
+    def __init__(self, period: Union[int, TimeStepSpec]) -> None:
+        if not isinstance(period, (int, TimeStepSpec)):
+            raise TypeError("period must be an integer or TimeStepSpec")
+        if isinstance(period, int):
+            if period < 0:
+                raise ValueError("period must be non-negative")
+            self.period = TimeStepSpec[::period]("steps") if period > 0 else TimeStepSpec([])("steps")
+        else:
+            self.period = period
 
-    def __init__(self, period: TimeStepSpec) -> None:
-        self.period = period
+    def check(self, *args, **kwargs):
+        """Validate that period is a valid TimeStepSpec."""
+        if not isinstance(self.period, TimeStepSpec):
+            raise TypeError("period must be a TimeStepSpec")
diff --git a/test/python/picongpu/quick/picmi/diagnostics/__init__.py b/test/python/picongpu/quick/picmi/diagnostics/__init__.py
index 2d4b6a07c1..8afd0d0fda 100644
--- a/test/python/picongpu/quick/picmi/diagnostics/__init__.py
+++ b/test/python/picongpu/quick/picmi/diagnostics/__init__.py
@@ -1,9 +1,10 @@
 """
 This file is part of PIConGPU.
 Copyright 2025 PIConGPU contributors
-Authors: Julian Lenz
+Authors: Julian Lenz, Masoud Afshari
 License: GPLv3+
 """
 
 # flake8: noqa
 from .timestepspec import *  # pyflakes.ignore
+from .auto import *  # pyflakes.ignore
diff --git a/test/python/picongpu/quick/picmi/diagnostics/auto.py b/test/python/picongpu/quick/picmi/diagnostics/auto.py
new file mode 100644
index 0000000000..bb20bc6439
--- /dev/null
+++ b/test/python/picongpu/quick/picmi/diagnostics/auto.py
@@ -0,0 +1,64 @@
+"""
+This file is part of PIConGPU.
+Copyright 2025 PIConGPU contributors
+Authors: Masoud Afshari
+License: GPLv3+
+"""
+
+import unittest
+import typeguard
+from picongpu.picmi.diagnostics import Auto, TimeStepSpec
+from picongpu.pypicongpu.output.auto import Auto as PyPIConGPUAuto
+from picongpu.pypicongpu.output.timestepspec import TimeStepSpec as PyPIConGPUTimeStepSpec
+
+
+TESTCASES_VALID = [
+    (10, [{"start": 0, "stop": -1, "step": 10}]),
+    (TimeStepSpec(slice(None, None, 10)), [{"start": 0, "stop": -1, "step": 10}]),
+]
+
+TESTCASES_INVALID = [
+    ("invalid", "period must be an integer or TimeStepSpec"),
+    (-10, "period must be non-negative"),
+]
+
+
+class PICMI_TestAuto(unittest.TestCase):
+    def test_valid_periods(self):
+        """Test Auto instantiation, validation, and conversion."""
+        for period, expected_specs in TESTCASES_VALID:
+            with self.subTest(period=period):
+                auto = Auto(period=period)
+                self.assertIsInstance(auto.period, TimeStepSpec)
+                auto.check()
+
+                # Convert to PyPIConGPUAuto
+                pypicongpu_auto = auto.get_as_pypicongpu(0.5, 200)
+                self.assertIsInstance(pypicongpu_auto, PyPIConGPUAuto)
+                self.assertIsInstance(pypicongpu_auto.period, PyPIConGPUTimeStepSpec)
+
+                # Validate rendered specs
+                serialized = pypicongpu_auto.get_rendering_context()
+                self.assertTrue(serialized["typeID"]["auto"])
+                self.assertEqual(serialized["data"]["period"]["specs"], expected_specs)
+
+    def test_invalid_period_type(self):
+        """Test invalid input types."""
+        with self.assertRaises(typeguard.TypeCheckError):
+            Auto(period="invalid")
+
+    def test_negative_period(self):
+        """Test negative integer period raises error."""
+        with self.assertRaisesRegex(ValueError, "period must be non-negative"):
+            Auto(period=-5)
+
+    def test_check_invalid_period(self):
+        """Test that check() catches wrong type."""
+        auto = Auto(period=10)
+        auto.period = "invalid"
+        with self.assertRaisesRegex(TypeError, "period must be a TimeStepSpec"):
+            auto.check()
+
+
+if __name__ == "__main__":
+    unittest.main()