diff --git a/README.rst b/README.rst
index 1668b50..1aacbec 100644
--- a/README.rst
+++ b/README.rst
@@ -20,6 +20,10 @@ It requires the following packages:
 - Pandas,
 - Rich.
 
+
+CLI
+***
+
 usage: roiloc [-h] -p PATH -i INPUTPATTERN [-r ROI [ROI ...]] -c CONTRAST [-b]
               [-t TRANSFORM] [-m MARGIN [MARGIN ...]] [--mask MASK]
               [--extracrops EXTRACROPS [EXTRACROPS ...]] [--savesteps]
@@ -57,6 +61,41 @@ arguments::
                         atlas).
 
 
+Python API
+**********
+
+Even if the CLI interface is the main use case, a Python API is also available since v0.2.0.
+
+The API syntax retakes sklearn's API syntax, with a ``RoiLocator`` class, having ``fit``, ``transform``, ``fit_transform`` and ``inverse_transform`` methods as seen below.
+
+.. code-block:: python
+
+    import ants
+    from roiloc.locator import RoiLocator
+
+    image = ants.image_read("./sub00_t2w.nii.gz",
+                            reorient="LPI")
+
+    locator = RoiLocator(contrast="t2", roi="hippocampus", bet=False)
+
+    # Fit the locator and get the transformed MRIs
+    right, left = locator.fit_transform(image)
+    # Coordinates can be obtained through the `coords` attribute
+    print(locator.get_coords())
+
+    # Let 'model' be a segmentation model of the hippocampus
+    right_seg = model(right)
+    left_seg = model(left)
+
+    # Transform the segmentation back to the original image
+    right_seg = locator.inverse_transform(right_seg)
+    left_seg = locator.inverse_transform(left_seg)
+
+    # Save the resulting segmentations in the original space
+    ants.image_write(right_seg, "./sub00_hippocampus_right.nii.gz")
+    ants.image_write(left_seg, "./sub00_hippocampus_left.nii.gz")
+
+
 Installation
 ************
 
diff --git a/roiloc/locator.py b/roiloc/locator.py
index 8d1d9f8..a50bc13 100644
--- a/roiloc/locator.py
+++ b/roiloc/locator.py
@@ -4,11 +4,35 @@
 from ants.core import ANTsImage
 
 from .location import crop, get_coords
-from .registration import get_roi, register
+from .registration import get_roi
 from .template import get_atlas, get_mni, get_roi_indices
 
 
 class RoiLocator:
+    """Crop an MRI image to a ROI.
+
+    Args:
+        contrast (str): Contrast to use for registration.
+        roi (str): ROI to use for registration.
+        bet (bool, optional): Use brain extracted MNI template. Defaults to False.
+        transform_type (str, optional): Type of transformation for the registration.
+                                        Defaults to "AffineFast".
+        margin (list, optional): Margin to apply. Defaults to [4, 4, 4].
+        mask (Optional[ANTsImage], optional): Brain mask to improve registration quality.
+                                              Defaults to None.
+
+    Attributes:
+        coords (dict): Dictionary of coordinates for each side of the ROI.
+        _fwdtransforms (list): List of forward transforms.
+        _invtransforms (list): List of inverse transforms.
+        _mni (ANTsImage): MNI template.
+        _atlas (ANTsImage): CerebrA atlas image.
+        _roi_idx (list): List of indices for the ROI in the CerebrA atlas.
+        _image (ANTsImage): Input image used to inverse transform.
+
+    Exemples:
+        >>> from roiloc.locator import RoiLocator
+    """
 
     def __init__(self,
                  contrast: str,
@@ -17,6 +41,7 @@ def __init__(self,
                  transform_type: str = "AffineFast",
                  margin: list = [4, 4, 4],
                  mask: Optional[ANTsImage] = None):
+
         self.transform_type = transform_type
         self.margin = margin
         self.mask = mask
@@ -31,9 +56,19 @@ def __init__(self,
         self.coords = {}
 
     def get_coords(self) -> dict:
+        """Get the coordinates of the ROI.
+
+        Returns:
+            dict: Dictionary of coordinates for each side of the ROI.
+        """
         return self.coords
 
     def fit(self, image: ANTsImage):
+        """Fit the ROI to the image and set coords.
+
+        Args:
+            image (ANTsImage): Image to fit the ROI to.
+        """
         self._image = image
 
         registration = ants.registration(fixed=image,
@@ -59,16 +94,40 @@ def fit(self, image: ANTsImage):
             self.coords[side] = coords
 
     def transform(self, image: ANTsImage) -> list:
+        """Crop the image to the ROI.
+
+        Args:
+            image (ANTsImage): Image to transform.
+
+        Returns:
+            list: List of transformed images.
+        """
         return [
             crop(image, self.coords[side], log_coords=False, ri=True)
             for side in ["right", "left"]
         ]
 
     def fit_transform(self, image: ANTsImage) -> list:
+        """Fit the ROI to the image and transform.
+
+        Args:
+            image (ANTsImage): Image to fit the ROI to.
+
+        Returns:
+            list: List of transformed images.
+        """
         self.fit(image)
         return self.transform(image)
 
     def inverse_transform(self, image: ANTsImage) -> ANTsImage:
+        """Inverse transform the image to the native space.
+
+        Args:
+            image (ANTsImage): Image to inverse transform.
+
+        Returns:
+            ANTsImage: Inverse transformed image.
+        """
         return ants.decrop_image(image, self._image)