diff --git a/docs/src/conf.py b/docs/src/conf.py
index c7e5abacb..e9373df1c 100644
--- a/docs/src/conf.py
+++ b/docs/src/conf.py
@@ -9,7 +9,7 @@
 
 
 # When importing metatensor-torch, this will change the definition of the classes
-# to include in the documentation
+# to include the documentation
 os.environ["METATENSOR_IMPORT_FOR_SPHINX"] = "1"
 os.environ["RASCALINE_IMPORT_FOR_SPHINX"] = "1"
 
diff --git a/docs/src/dev-docs/new-architecture.rst b/docs/src/dev-docs/new-architecture.rst
index 2921a59a1..7d744d294 100644
--- a/docs/src/dev-docs/new-architecture.rst
+++ b/docs/src/dev-docs/new-architecture.rst
@@ -32,10 +32,10 @@ to these lines
         checkpoint_dir="path",
     )
 
-    model.save_checkpoint("final.ckpt")
+    model.save_checkpoint("model.ckpt")
 
     mts_atomistic_model = model.export()
-    mts_atomistic_model.export("path", collect_extensions="extensions-dir/")
+    mts_atomistic_model.export("model.pt", collect_extensions="extensions/")
 
 
 In order to follow this, a new architectures has two define two classes
diff --git a/src/metatensor/models/__main__.py b/src/metatensor/models/__main__.py
index 1c2157ae0..a4bc25c02 100644
--- a/src/metatensor/models/__main__.py
+++ b/src/metatensor/models/__main__.py
@@ -20,21 +20,6 @@
 from .utils.logging import setup_logging
 
 
-# This import is necessary to avoid errors when loading an
-# exported alchemical model, which depends on sphericart-torch.
-# TODO: Remove this when https://github.com/lab-cosmo/metatensor/issues/512
-# is ready
-try:
-    import sphericart.torch  # noqa: F401
-except ImportError:
-    pass
-
-try:
-    import rascaline.torch  # noqa: F401
-except ImportError:
-    pass
-
-
 logger = logging.getLogger(__name__)
 
 
diff --git a/src/metatensor/models/cli/eval.py b/src/metatensor/models/cli/eval.py
index b6f5ad5e8..7633d554e 100644
--- a/src/metatensor/models/cli/eval.py
+++ b/src/metatensor/models/cli/eval.py
@@ -58,7 +58,7 @@ def _add_eval_model_parser(subparser: argparse._SubParsersAction) -> None:
     )
     parser.add_argument(
         "-e",
-        "--extdir",
+        "--extensions-dir",
         type=str,
         required=False,
         dest="extensions_directory",
diff --git a/src/metatensor/models/cli/export.py b/src/metatensor/models/cli/export.py
index 5c452b425..121cc5a2c 100644
--- a/src/metatensor/models/cli/export.py
+++ b/src/metatensor/models/cli/export.py
@@ -63,4 +63,4 @@ def export_model(model: Any, output: Union[Path, str] = "exported-model.pt") ->
         torch.jit.save(model, path)
     else:
         mts_atomistic_model = model.export()
-        mts_atomistic_model.export(path)
+        mts_atomistic_model.export(path, collect_extensions="extensions")
diff --git a/src/metatensor/models/cli/train.py b/src/metatensor/models/cli/train.py
index 57683dfc6..2e55f79e3 100644
--- a/src/metatensor/models/cli/train.py
+++ b/src/metatensor/models/cli/train.py
@@ -389,7 +389,7 @@ def train_model(
         raise ArchitectureError(e)
 
     mts_atomistic_model = model.export()
-    mts_atomistic_model.export(str(output_checked))
+    mts_atomistic_model.export(str(output_checked), collect_extensions="extensions")
 
     ###########################
     # EVALUATE FINAL MODEL ####
diff --git a/src/metatensor/models/utils/evaluate_model.py b/src/metatensor/models/utils/evaluate_model.py
index 22e5689b1..aaf5e8fe2 100644
--- a/src/metatensor/models/utils/evaluate_model.py
+++ b/src/metatensor/models/utils/evaluate_model.py
@@ -22,7 +22,8 @@
     "ignore",
     category=UserWarning,
     message="neighbor",
-)  # TODO: this is not filtering out the warning for some reason
+)  # TODO: this is not filtering out the warning for some reason, therefore:
+warnings.filterwarnings("ignore")  # ignore all warnings if not in debug mode
 
 
 def evaluate_model(