diff --git a/fancy_gym/envs/registry.py b/fancy_gym/envs/registry.py
index 5176699..c3eb896 100644
--- a/fancy_gym/envs/registry.py
+++ b/fancy_gym/envs/registry.py
@@ -1,4 +1,4 @@
-from typing import Tuple, Union
+from typing import Tuple, Union, Callable, List, Dict, Any, Optional
 
 import copy
 import importlib
@@ -113,14 +113,41 @@ MOVEMENT_PRIMITIVE_ENVIRONMENTS_FOR_NS = {}
 
 
 def register(
-        id,
-        entry_point=None,
-        mp_wrapper=DefaultMPWrapper,
-        register_step_based=True,  # TODO: Detect
-        add_mp_types=KNOWN_MPS,
-        mp_config_override={},
+        id: str,
+        entry_point: Optional[Union[Callable, str]] = None,
+        mp_wrapper: RawInterfaceWrapper = DefaultMPWrapper,
+        register_step_based: bool = True,  # TODO: Detect
+        add_mp_types: List[str] = KNOWN_MPS,
+        mp_config_override: Dict[str, Any] = {},
         **kwargs
 ):
+    """
+    Registers a Gymnasium environment, including Movement Primitives (MP) versions.
+    If you only want to register MP versions for an already registered environment, use fancy_gym.upgrade instead.
+
+    Args:
+        id (str): The unique identifier for the environment.
+        entry_point (Optional[Union[Callable, str]]): The entry point for creating the environment.
+        mp_wrapper (RawInterfaceWrapper): The MP wrapper for the environment.
+        register_step_based (bool): Whether to also register the raw srtep-based version of the environment (default True).
+        add_mp_types (List[str]): List of additional MP types to register.
+        mp_config_override (Dict[str, Any]): Dictionary for overriding MP configuration.
+        **kwargs: Additional keyword arguments which are passed to the environment constructor.
+
+    Notes:
+        - When `register_step_based` is True, the raw environment will also be registered to gymnasium otherwise only mp-versions will be registered.
+        - `entry_point` can be given as a string, allowing the same notation as gymnasium.
+        - If `id` already exists in the Gymnasium registry and `register_step_based` is True,
+          a warning message will be printed, suggesting to set `register_step_based=False` or use `fancy_gym.upgrade`.
+
+    Example:
+        To register a step-based environment with Movement Primitive versions (will use default mp_wrapper):
+        >>> register("MyEnv-v0", MyEnvClass"my_module:MyEnvClass")
+
+        The entry point can also be provided as a string:
+        >>> register("MyEnv-v0", "my_module:MyEnvClass")
+
+    """
     if register_step_based and id in gym_registry:
         print(f'[Info] Gymnasium env with id "{id}" already exists. You should supply register_step_based=False or use fancy_gym.upgrade if you only want to register mp versions of an existing env.')
     if register_step_based:
@@ -135,23 +162,48 @@ def register(
 
 
 def upgrade(
-        id,
-        mp_wrapper=DefaultMPWrapper,
-        add_mp_types=KNOWN_MPS,
-        base_id=None,
-        mp_config_override={},
+        id: str,
+        mp_wrapper: RawInterfaceWrapper = DefaultMPWrapper,
+        add_mp_types: List[str] = KNOWN_MPS,
+        base_id: Optional[str] = None,
+        mp_config_override: Dict[str, Any] = {},
 ):
+    """
+    Upgrades an existing Gymnasium environment to include Movement Primitives (MP) versions.
+    We expect the raw step-based env to be already registered with gymnasium. Otherwise please use fancy_gym.register instead.
+
+    Args:
+        id (str): The unique identifier for the environment.
+        mp_wrapper (RawInterfaceWrapper): The MP wrapper for the environment (default is DefaultMPWrapper).
+        add_mp_types (List[str]): List of additional MP types to register (default is KNOWN_MPS).
+        base_id (Optional[str]): The unique identifier for the environment to upgrade. Will use id if non is provided. Can be defined to allow multiple registrations of different versions for the same step-based environment.
+        mp_config_override (Dict[str, Any]): Dictionary for overriding MP configuration.
+
+    Notes:
+        - The `id` parameter should match the ID of the existing Gymnasium environment you wish to upgrade. You can also pick a new one, but then `base_id` needs to be provided.
+        - The `mp_wrapper` parameter specifies the MP wrapper to use, allowing for customization.
+        - `add_mp_types` can be used to specify additional MP types to register alongside the base environment.
+        - The `base_id` parameter should match the ID of the existing Gymnasium environment you wish to upgrade.
+        - `mp_config_override` allows for customizing MP configuration if needed.
+
+    Example:
+        To upgrade an existing environment with MP versions:
+        >>> upgrade("MyEnv-v0", mp_wrapper=CustomMPWrapper)
+
+        To upgrade an existing environment with custom MP types and configuration:
+        >>> upgrade("MyEnv-v0", mp_wrapper=CustomMPWrapper, add_mp_types=["ProDMP", "DMP"], mp_config_override={"param": 42})
+    """
     if not base_id:
         base_id = id
     register_mps(id, base_id, mp_wrapper, add_mp_types, mp_config_override)
 
 
-def register_mps(id, base_id, mp_wrapper, add_mp_types=KNOWN_MPS, mp_config_override={}):
+def register_mps(id: str, base_id: str, mp_wrapper: RawInterfaceWrapper, add_mp_types: List[str] = KNOWN_MPS, mp_config_override: Dict[str, Any] = {}):
     for mp_type in add_mp_types:
         register_mp(id, base_id, mp_wrapper, mp_type, mp_config_override.get(mp_type, {}))
 
 
-def register_mp(id, base_id, mp_wrapper, mp_type, mp_config_override={}):
+def register_mp(id: str, base_id: str, mp_wrapper: RawInterfaceWrapper, mp_type: List[str], mp_config_override: Dict[str, Any] = {}):
     assert mp_type in KNOWN_MPS, 'Unknown mp_type'
     assert id not in ALL_MOVEMENT_PRIMITIVE_ENVIRONMENTS[mp_type], f'The environment {id} is already registered for {mp_type}.'