diff --git a/mace/calculators/__init__.py b/mace/calculators/__init__.py
index cb2a16f88..3315275ad 100644
--- a/mace/calculators/__init__.py
+++ b/mace/calculators/__init__.py
@@ -1,9 +1,11 @@
 from .foundations_models import mace_anicc, mace_mp, mace_off, mace_omol, mace_polar
 from .lammps_mace import LAMMPS_MACE
 from .mace import MACECalculator
+from .mace_torchsim import MaceTorchSimModel
 
 __all__ = [
     "MACECalculator",
+    "MaceTorchSimModel",
     "LAMMPS_MACE",
     "mace_mp",
     "mace_off",
diff --git a/tests/test_torchsim.py b/tests/test_torchsim.py
index 68ec7b752..9ef0d9548 100644
--- a/tests/test_torchsim.py
+++ b/tests/test_torchsim.py
@@ -8,14 +8,19 @@
 import numpy as np
 import pytest
 import torch
-from ase import build
+
+from mace.calculators import mace_mp, mace_off
 
 try:
     import torch_sim as ts
-
-    TORCHSIM_AVAILABLE = True
-except ImportError:
-    TORCHSIM_AVAILABLE = False
+    from torch_sim.models.interface import validate_model_outputs
+    from torch_sim.testing import (
+        SIMSTATE_BULK_GENERATORS,
+        SIMSTATE_MOLECULE_GENERATORS,
+        assert_model_calculator_consistency,
+    )
+except (ImportError, ModuleNotFoundError):
+    pytest.skip("Skipping torch-sim tests due to ImportError", allow_module_level=True)
 
 try:
     import cuequivariance as cue  # noqa: F401
@@ -24,13 +29,95 @@
 except ImportError:
     CUET_AVAILABLE = False
 
-pytestmark = pytest.mark.skipif(
-    not TORCHSIM_AVAILABLE, reason="torch-sim not installed"
-)
+from mace.calculators.mace_torchsim import MaceTorchSimModel
 
 pytest_mace_dir = Path(__file__).parent.parent
 run_train = Path(__file__).parent.parent / "mace" / "cli" / "run_train.py"
 
+DEVICE = torch.device("cpu")
+DTYPE = torch.float64
+MACE_MP_MODEL = "small-0b"
+MACE_OFF_MODEL = "small"
+
+
+def _to_dtype_name(dtype: torch.dtype) -> str:
+    if dtype == torch.float32:
+        return "float32"
+    if dtype == torch.float64:
+        return "float64"
+    raise ValueError(f"Unsupported dtype {dtype}")
+
+
+# ---------------------------------------------------------------------------
+# Fixtures for foundation-model tests
+# ---------------------------------------------------------------------------
+
+
+@pytest.fixture(scope="module")
+def raw_mace_mp_model():
+    return mace_mp(
+        model=MACE_MP_MODEL,
+        device=str(DEVICE),
+        default_dtype=_to_dtype_name(DTYPE),
+        return_raw_model=True,
+    )
+
+
+@pytest.fixture(scope="module")
+def raw_mace_off_model():
+    return mace_off(
+        model=MACE_OFF_MODEL,
+        device=str(DEVICE),
+        default_dtype=_to_dtype_name(DTYPE),
+        return_raw_model=True,
+    )
+
+
+@pytest.fixture
+def ase_mace_mp_calculator():
+    return mace_mp(
+        model=MACE_MP_MODEL,
+        device=str(DEVICE),
+        default_dtype=_to_dtype_name(DTYPE),
+        dispersion=False,
+    )
+
+
+@pytest.fixture
+def ase_mace_off_calculator():
+    return mace_off(
+        model=MACE_OFF_MODEL,
+        device=str(DEVICE),
+        default_dtype=_to_dtype_name(DTYPE),
+    )
+
+
+@pytest.fixture
+def ts_mace_mp_model(raw_mace_mp_model):
+    return MaceTorchSimModel(
+        model=raw_mace_mp_model,
+        device=DEVICE,
+        dtype=DTYPE,
+        compute_forces=True,
+        compute_stress=True,
+    )
+
+
+@pytest.fixture
+def ts_mace_off_model(raw_mace_off_model):
+    return MaceTorchSimModel(
+        model=raw_mace_off_model,
+        device=DEVICE,
+        dtype=DTYPE,
+        compute_forces=True,
+        compute_stress=False,
+    )
+
+
+# ---------------------------------------------------------------------------
+# Fixtures for locally-trained-model tests
+# ---------------------------------------------------------------------------
+
 
 @pytest.fixture(scope="module")
 def trained_model_path(tmp_path_factory):
@@ -123,6 +210,71 @@ def water_atoms():
     return atoms
 
 
+# ---------------------------------------------------------------------------
+# Foundation-model tests
+# ---------------------------------------------------------------------------
+
+
+@pytest.mark.parametrize("sim_state_name", ("si_sim_state", "rattled_si_sim_state"))
+def test_torch_sim_mace_mp_consistency(
+    sim_state_name, ts_mace_mp_model, ase_mace_mp_calculator
+):
+    sim_state = SIMSTATE_BULK_GENERATORS[sim_state_name](DEVICE, DTYPE)
+    assert_model_calculator_consistency(
+        model=ts_mace_mp_model,
+        calculator=ase_mace_mp_calculator,
+        sim_state=sim_state,
+    )
+
+
+@pytest.mark.parametrize("sim_state_name", ("benzene_sim_state",))
+def test_torch_sim_mace_off_consistency(
+    sim_state_name, ts_mace_off_model, ase_mace_off_calculator
+):
+    sim_state = SIMSTATE_MOLECULE_GENERATORS[sim_state_name](DEVICE, DTYPE)
+    assert_model_calculator_consistency(
+        model=ts_mace_off_model,
+        calculator=ase_mace_off_calculator,
+        sim_state=sim_state,
+    )
+
+
+@pytest.mark.parametrize("dtype", (torch.float32, torch.float64))
+def test_torch_sim_mace_dtype_smoke(raw_mace_mp_model, dtype: torch.dtype):
+    model = MaceTorchSimModel(
+        model=raw_mace_mp_model,
+        device=DEVICE,
+        dtype=dtype,
+        compute_forces=True,
+        compute_stress=True,
+    )
+    state = SIMSTATE_BULK_GENERATORS["si_sim_state"](DEVICE, dtype)
+    output = model(state)
+
+    assert output["energy"].shape == (1,)
+    assert torch.is_floating_point(output["energy"])
+    assert output["forces"].shape == state.positions.shape
+    assert torch.is_floating_point(output["forces"])
+    assert output["stress"].shape == (1, 3, 3)
+
+
+def test_torch_sim_mace_off_output_keys(ts_mace_off_model):
+    state = SIMSTATE_MOLECULE_GENERATORS["benzene_sim_state"](DEVICE, DTYPE)
+    output = ts_mace_off_model(state)
+    assert "energy" in output
+    assert "forces" in output
+    assert "stress" not in output
+
+
+def test_torch_sim_mace_validate_outputs(ts_mace_mp_model):
+    validate_model_outputs(ts_mace_mp_model, DEVICE, DTYPE)
+
+
+# ---------------------------------------------------------------------------
+# Locally-trained-model tests
+# ---------------------------------------------------------------------------
+
+
 def test_torchsim_basic(trained_model_path, water_atoms):
     from mace.calculators.mace_torchsim import MaceTorchSimModel