diff --git a/gazu/context.py b/gazu/context.py
index 1e39d02..8ba9340 100644
--- a/gazu/context.py
+++ b/gazu/context.py
@@ -1,3 +1,5 @@
+from __future__ import annotations
+
 from . import user as gazu_user
 from . import project as gazu_project
 from . import asset as gazu_asset
@@ -6,7 +8,7 @@
 from . import scene as gazu_scene
 
 
-def all_open_projects(user_context=False):
+def all_open_projects(user_context: bool = False) -> list[dict]:
     """
     Return the list of projects for which the user has a task.
     """
@@ -16,7 +18,9 @@ def all_open_projects(user_context=False):
         return gazu_project.all_open_projects()
 
 
-def all_assets_for_project(project, user_context=False):
+def all_assets_for_project(
+    project: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of assets for which the user has a task.
     """
@@ -26,7 +30,9 @@ def all_assets_for_project(project, user_context=False):
         return gazu_asset.all_assets_for_project(project)
 
 
-def all_asset_types_for_project(project, user_context=False):
+def all_asset_types_for_project(
+    project: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of asset types for which the user has a task.
     """
@@ -37,8 +43,8 @@ def all_asset_types_for_project(project, user_context=False):
 
 
 def all_assets_for_asset_type_and_project(
-    project, asset_type, user_context=False
-):
+    project: str | dict, asset_type: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of assets for given project and asset_type and for which
     the user has a task.
@@ -51,7 +57,9 @@ def all_assets_for_asset_type_and_project(
         return gazu_asset.all_assets_for_project_and_type(project, asset_type)
 
 
-def all_task_types_for_asset(asset, user_context=False):
+def all_task_types_for_asset(
+    asset: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of tasks for given asset and current user.
     """
@@ -61,7 +69,9 @@ def all_task_types_for_asset(asset, user_context=False):
         return gazu_task.all_task_types_for_asset(asset)
 
 
-def all_task_types_for_shot(shot, user_context=False):
+def all_task_types_for_shot(
+    shot: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of tasks for given shot and current user.
     """
@@ -71,7 +81,9 @@ def all_task_types_for_shot(shot, user_context=False):
         return gazu_task.all_task_types_for_shot(shot)
 
 
-def all_task_types_for_scene(scene, user_context=False):
+def all_task_types_for_scene(
+    scene: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of tasks for given scene and current user.
     """
@@ -81,7 +93,9 @@ def all_task_types_for_scene(scene, user_context=False):
         return gazu_task.all_task_types_for_scene(scene)
 
 
-def all_task_types_for_sequence(sequence, user_context=False):
+def all_task_types_for_sequence(
+    sequence: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of tasks for given sequence and current user.
     """
@@ -91,7 +105,9 @@ def all_task_types_for_sequence(sequence, user_context=False):
         return gazu_task.all_task_types_for_sequence(sequence)
 
 
-def all_sequences_for_project(project, user_context=False):
+def all_sequences_for_project(
+    project: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of sequences for given project and current user.
     """
@@ -101,7 +117,9 @@ def all_sequences_for_project(project, user_context=False):
         return gazu_shot.all_sequences_for_project(project)
 
 
-def all_scenes_for_project(project, user_context=False):
+def all_scenes_for_project(
+    project: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of scenes for given project and current user.
     """
@@ -111,7 +129,9 @@ def all_scenes_for_project(project, user_context=False):
         return gazu_scene.all_scenes(project)
 
 
-def all_shots_for_sequence(sequence, user_context=False):
+def all_shots_for_sequence(
+    sequence: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of shots for given sequence and current user.
     """
@@ -121,7 +141,9 @@ def all_shots_for_sequence(sequence, user_context=False):
         return gazu_shot.all_shots_for_sequence(sequence)
 
 
-def all_scenes_for_sequence(sequence, user_context=False):
+def all_scenes_for_sequence(
+    sequence: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of scenes for given sequence and current user.
     """
@@ -131,7 +153,9 @@ def all_scenes_for_sequence(sequence, user_context=False):
         return gazu_scene.all_scenes_for_sequence(sequence)
 
 
-def all_sequences_for_episode(episode, user_context=False):
+def all_sequences_for_episode(
+    episode: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of shots for given sequence and current user.
     """
@@ -141,7 +165,9 @@ def all_sequences_for_episode(episode, user_context=False):
         return gazu_shot.all_sequences_for_episode(episode)
 
 
-def all_episodes_for_project(project, user_context=False):
+def all_episodes_for_project(
+    project: str | dict, user_context: bool = False
+) -> list[dict]:
     """
     Return the list of shots for given sequence and current user.
     """
diff --git a/gazu/edit.py b/gazu/edit.py
index d7922e1..1ef8600 100644
--- a/gazu/edit.py
+++ b/gazu/edit.py
@@ -1,6 +1,9 @@
+from __future__ import annotations
+
 from . import client as raw
 
 from .cache import cache
+from .client import KitsuClient
 from .helpers import normalize_model_parameter
 from gazu.sorting import sort_by_name
 
@@ -8,7 +11,7 @@
 
 
 @cache
-def get_edit(edit_id, client=default):
+def get_edit(edit_id: str, client: KitsuClient = default) -> dict:
     """
     Args:
         edit_id (str): ID of claimed edit.
@@ -20,7 +23,9 @@ def get_edit(edit_id, client=default):
 
 
 @cache
-def get_edit_by_name(project, edit_name, client=default):
+def get_edit_by_name(
+    project: str | dict, edit_name: str, client: KitsuClient = default
+) -> dict | None:
     """
     Args:
         project (str / dict): The project dict or the project ID.
@@ -38,7 +43,7 @@ def get_edit_by_name(project, edit_name, client=default):
 
 
 @cache
-def get_edit_url(edit, client=default):
+def get_edit_url(edit: str | dict, client: KitsuClient = default) -> str:
     """
     Args:
         edit (str / dict): The edit dict or the edit ID.
@@ -62,7 +67,9 @@ def get_edit_url(edit, client=default):
 
 
 @cache
-def all_edits_for_project(project, client=default):
+def all_edits_for_project(
+    project: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Args:
         project (str / dict): The project dict or the project ID.
@@ -76,7 +83,9 @@ def all_edits_for_project(project, client=default):
 
 
 @cache
-def all_previews_for_edit(edit, client=default):
+def all_previews_for_edit(
+    edit: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Args:
         edit (str / dict): The edit dict or the edit ID.
@@ -89,13 +98,13 @@ def all_previews_for_edit(edit, client=default):
 
 
 def new_edit(
-    project,
-    name,
-    description=None,
-    data={},
-    episode=None,
-    client=default,
-):
+    project: str | dict,
+    name: str,
+    description: str | None = None,
+    data: dict = {},
+    episode: str | dict | None = None,
+    client: KitsuClient = default,
+) -> dict:
     """
     Create an edit for given project (and episode if given).
     Allow to set metadata too.
@@ -128,12 +137,20 @@ def new_edit(
         return edit
 
 
-def remove_edit(edit, force=False, client=default):
+def remove_edit(
+    edit: str | dict, force: bool = False, client: KitsuClient = default
+) -> str:
     """
     Remove given edit from database.
 
+    If the Edit has tasks linked to it, this will by default mark the
+    Edit as canceled. Deletion can be forced regardless of task links
+    with the `force` parameter.
+
     Args:
-        edit (dict / str): Edit to remove.
+        edit (str / dict): Edit to remove.
+        force (bool): Whether to force deletion of the edit regardless of
+            whether it has links to tasks.
     """
     edit = normalize_model_parameter(edit)
     path = "data/edits/%s" % edit["id"]
@@ -143,7 +160,7 @@ def remove_edit(edit, force=False, client=default):
     return raw.delete(path, params, client=client)
 
 
-def update_edit(edit, client=default):
+def update_edit(edit: dict, client: KitsuClient = default) -> dict:
     """
     Save given edit data into the API. Metadata are fully replaced by the ones
     set on given edit.
@@ -157,13 +174,15 @@ def update_edit(edit, client=default):
     return raw.put("data/entities/%s" % edit["id"], edit, client=client)
 
 
-def update_edit_data(edit, data={}, client=default):
+def update_edit_data(
+    edit: str | dict, data: dict = {}, client: KitsuClient = default
+) -> dict:
     """
     Update the metadata for the provided edit. Keys that are not provided are
     not changed.
 
     Args:
-        edit (dict / ID): The edit dict or ID to save in database.
+        edit (str / dict): The edit dict or ID to save in database.
         data (dict): Free field to set metadata of any kind.
 
     Returns:
diff --git a/gazu/encoder.py b/gazu/encoder.py
index 655705c..b5aedd7 100644
--- a/gazu/encoder.py
+++ b/gazu/encoder.py
@@ -1,6 +1,8 @@
 import json
 import datetime
 
+from typing import Any
+
 
 class CustomJSONEncoder(json.JSONEncoder):
     """
@@ -8,7 +10,7 @@ class CustomJSONEncoder(json.JSONEncoder):
     The standard does not want to assum how you handle dates.
     """
 
-    def default(self, obj):
+    def default(self, obj: Any) -> Any:
         if isinstance(obj, datetime.datetime):
             return obj.isoformat()
 
diff --git a/gazu/entity.py b/gazu/entity.py
index 2f23f04..bd45706 100644
--- a/gazu/entity.py
+++ b/gazu/entity.py
@@ -1,6 +1,9 @@
+from __future__ import annotations
+
 from . import client as raw
 
 from .cache import cache
+from .client import KitsuClient
 from .sorting import sort_by_name
 from .helpers import normalize_model_parameter
 
@@ -8,7 +11,7 @@
 
 
 @cache
-def all_entities(client=default):
+def all_entities(client: KitsuClient = default) -> list[dict]:
     """
     Returns:
         list: Retrieve all entities
@@ -17,7 +20,7 @@ def all_entities(client=default):
 
 
 @cache
-def all_entity_types(client=default):
+def all_entity_types(client: KitsuClient = default) -> list[dict]:
     """
     Returns:
         list: Entity types listed in database.
@@ -26,7 +29,7 @@ def all_entity_types(client=default):
 
 
 @cache
-def get_entity(entity_id, client=default):
+def get_entity(entity_id: str, client: KitsuClient = default) -> dict:
     """
     Args:
         entity_id (str): ID of claimed entity.
@@ -39,11 +42,15 @@ def get_entity(entity_id, client=default):
 
 
 @cache
-def get_entity_by_name(entity_name, project=None, client=default):
+def get_entity_by_name(
+    entity_name: str,
+    project: str | dict | None = None,
+    client: KitsuClient = default,
+) -> dict | None:
     """
     Args:
-        name (str): The name of the claimed entity.
-        project (str, dict): Project ID or dict.
+        entity_name (str): The name of the claimed entity.
+        project (str / dict): Project ID or dict.
 
     Returns:
         Retrieve entity matching given name (and project if given).
@@ -56,10 +63,13 @@ def get_entity_by_name(entity_name, project=None, client=default):
 
 
 @cache
-def get_entity_type(entity_type_id, client=default):
+def get_entity_type(
+    entity_type_id: str, client: KitsuClient = default
+) -> dict:
     """
     Args:
         entity_type_id (str): ID of claimed entity type.
+
     Returns:
         Retrieve entity type matching given ID (It can be an entity type of any
         kind).
@@ -68,7 +78,9 @@ def get_entity_type(entity_type_id, client=default):
 
 
 @cache
-def get_entity_type_by_name(entity_type_name, client=default):
+def get_entity_type_by_name(
+    entity_type_name: str, client: KitsuClient = default
+) -> dict | None:
     """
     Args:
         entity_type_name (str): The name of the claimed entity type
@@ -82,17 +94,17 @@ def get_entity_type_by_name(entity_type_name, client=default):
 
 
 @cache
-def guess_from_path(project_id, path, sep="/"):
+def guess_from_path(project_id: str, path: str, sep: str = "/") -> list[dict]:
     """
     Get list of possible project file tree templates matching a file path
     and data ids corresponding to template tokens.
 
     Args:
         project_id (str): Project id of given file
-        file_path (str): Path to a file
+        path (str): Path to a file
         sep (str): File path separator, defaults to "/"
     Returns:
-        list: dictionnaries with the corresponding entities and template name.
+        list: dictionaries with the corresponding entities and template name.
     """
     return raw.post(
         "/data/entities/guess_from_path",
@@ -100,38 +112,52 @@ def guess_from_path(project_id, path, sep="/"):
     )
 
 
-def new_entity_type(name, client=default):
+def new_entity_type(name: str, client: KitsuClient = default) -> dict:
     """
     Creates an entity type with the given name.
 
     Args:
-        name (str, client=default): The name of the entity type
+        name (str): The name of the entity type
 
     Returns:
         dict: The created entity type
+
+    Raises:
+        gazu.exception.ParameterException:
+            If an entity type with that name already exists.
     """
     data = {"name": name}
     return raw.create("entity-types", data, client=client)
 
 
-def remove_entity_type(entity_type, client=default):
+def remove_entity_type(
+    entity_type: str | dict, client: KitsuClient = default
+) -> str:
     """
     Remove given entity type from database.
 
     Args:
-        entity_type (dict / str): Entity type to remove.
+        entity_type (str / dict): Entity type to remove.
     """
     entity_type = normalize_model_parameter(entity_type)
     path = "data/entity-types/%s" % entity_type["id"]
     return raw.delete(path, client=client)
 
 
-def remove_entity(entity, force=False, client=default):
+def remove_entity(
+    entity: str | dict, force: bool = False, client: KitsuClient = default
+) -> str:
     """
     Remove given entity from database.
 
+    If the Entity has tasks linked to it, this will by default mark the
+    Entity as canceled. Deletion can be forced regardless of task links
+    with the `force` parameter.
+
     Args:
         entity (dict): Entity to remove.
+        force (bool): Whether to force deletion of the entity regardless of
+            whether it has links to tasks.
     """
     entity = normalize_model_parameter(entity)
     path = "data/entities/%s" % entity["id"]
@@ -141,10 +167,13 @@ def remove_entity(entity, force=False, client=default):
     return raw.delete(path, params, client=client)
 
 
-def all_entities_with_tasks_linked_to_entity(entity, client=default):
+def all_entities_with_tasks_linked_to_entity(
+    entity: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Args:
-        entity (dict): Entity to get linked entities.
+        entity (str / dict): Entity to get linked entities.
+
     Returns:
         list: Retrieve all entities linked to given entity.
     """
diff --git a/gazu/events.py b/gazu/events.py
index 0bace91..3290aef 100644
--- a/gazu/events.py
+++ b/gazu/events.py
@@ -4,10 +4,12 @@
 import signal
 import socketio
 
+from typing import Any, Callable
+
 from engineio.base_client import signal_handler
 from .exception import AuthFailedException
 
-from .client import default_client, get_event_host, make_auth_header
+from .client import default_client, get_event_host, KitsuClient, make_auth_header
 
 
 if os.name == "nt":
@@ -25,23 +27,23 @@ def WindowsSignalHandler(event):
 
 
 class EventsNamespace(socketio.ClientNamespace):
-    def on_connect(self):
+    def on_connect(self) -> None:
         pass
 
-    def on_disconnect(self):
+    def on_disconnect(self) -> None:
         pass
 
-    def on_error(self, data):
+    def on_error(self, data: str) -> str:
         return connect_error(data)
 
 
 def init(
-    client=default_client,
-    ssl_verify=False,
-    reconnection=True,
-    logger=False,
-    **kwargs
-):
+    client: KitsuClient = default_client,
+    ssl_verify: bool = False,
+    reconnection: bool = True,
+    logger: bool = False,
+    **kwargs: Any
+) -> socketio.Client:
     """
     Init configuration for SocketIO client.
 
@@ -61,13 +63,15 @@ def init(
     return event_client
 
 
-def connect_error(data):
+def connect_error(data: str) -> str:
     print("The connection failed!")
     print(data)
     return data
 
 
-def add_listener(event_client, event_name, event_handler):
+def add_listener(
+    event_client: socketio.Client, event_name: str, event_handler: Callable
+) -> socketio.Client:
     """
     Set a listener that reacts to a given event.
     """
@@ -75,7 +79,7 @@ def add_listener(event_client, event_name, event_handler):
     return event_client
 
 
-def run_client(event_client):
+def run_client(event_client: socketio.Client) -> socketio.Client:
     """
     Run event client (it blocks current thread). It listens to all events
     configured.
diff --git a/gazu/files.py b/gazu/files.py
index 7392d56..76f2ed5 100644
--- a/gazu/files.py
+++ b/gazu/files.py
@@ -1,13 +1,20 @@
+from __future__ import annotations
+
+from typing_extensions import Literal
+
+import requests
+
 from . import client as raw
 
 from .cache import cache
+from .client import KitsuClient
 from .helpers import normalize_model_parameter
 
 default = raw.default_client
 
 
 @cache
-def all_output_types(client=default):
+def all_output_types(client: KitsuClient = default) -> list[dict]:
     """
     Returns:
         list: Output types listed in database.
@@ -16,7 +23,9 @@ def all_output_types(client=default):
 
 
 @cache
-def all_output_types_for_entity(entity, client=default):
+def all_output_types_for_entity(
+    entity: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Args:
         entity (str / dict): The entity dict or the entity ID.
@@ -32,8 +41,8 @@ def all_output_types_for_entity(entity, client=default):
 
 @cache
 def all_output_types_for_asset_instance(
-    asset_instance, temporal_entity, client=default
-):
+    asset_instance: dict, temporal_entity: dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Returns:
         list: Output types for given asset instance and entity (shot or scene).
@@ -46,7 +55,9 @@ def all_output_types_for_asset_instance(
 
 
 @cache
-def get_output_type(output_type_id, client=default):
+def get_output_type(
+    output_type_id: str, client: KitsuClient = default
+) -> dict:
     """
     Args:
         output_type_id (str): ID of claimed output type.
@@ -58,7 +69,9 @@ def get_output_type(output_type_id, client=default):
 
 
 @cache
-def get_output_type_by_name(output_type_name, client=default):
+def get_output_type_by_name(
+    output_type_name: str, client: KitsuClient = default
+) -> dict | None:
     """
     Args:
         output_type_name (str): name of claimed output type.
@@ -71,7 +84,9 @@ def get_output_type_by_name(output_type_name, client=default):
     )
 
 
-def new_output_type(name, short_name, client=default):
+def new_output_type(
+    name: str, short_name: str, client: KitsuClient = default
+) -> dict:
     """
     Create a new output type in database.
 
@@ -91,7 +106,9 @@ def new_output_type(name, short_name, client=default):
 
 
 @cache
-def get_output_file(output_file_id, client=default):
+def get_output_file(
+    output_file_id: str, client: KitsuClient = default
+) -> dict:
     """
     Args:
         output_file_id (str): ID of claimed output file.
@@ -104,21 +121,26 @@ def get_output_file(output_file_id, client=default):
 
 
 @cache
-def get_output_file_by_path(path, client=default):
+def get_output_file_by_path(
+    path: str, client: KitsuClient = default
+) -> dict | None:
     """
     Args:
         path (str): Path of claimed output file.
 
     Returns:
-        dict: Output file matching given path.
+        dict: Output file matching given path, or None if there are no matches.
     """
     return raw.fetch_first("output-files", {"path": path}, client=client)
 
 
 @cache
 def get_all_working_files_for_entity(
-    entity, task=None, name=None, client=default
-):
+    entity: str | dict,
+    task: str | dict | None = None,
+    name: str | None = None,
+    client: KitsuClient = default,
+) -> list[dict]:
     """
     Retrieves all the working files of a given entity and specied parameters
     """
@@ -136,7 +158,9 @@ def get_all_working_files_for_entity(
 
 
 @cache
-def get_preview_file(preview_file_id, client=default):
+def get_preview_file(
+    preview_file_id: str, client: KitsuClient = default
+) -> dict:
     """
     Args:
         preview_file_id (str): ID of claimed preview file.
@@ -147,12 +171,23 @@ def get_preview_file(preview_file_id, client=default):
     return raw.fetch_one("preview-files", preview_file_id, client=client)
 
 
-def remove_preview_file(preview_file, force=False, client=default):
+def remove_preview_file(
+    preview_file: str | dict,
+    force: bool = False,
+    client: KitsuClient = default,
+) -> str:
     """
     Remove given preview file from database.
 
+    Depending on the configuration of the Kitsu server, the stored files linked
+    to the preview file may or may not be removed on deletion of a preview file.
+    The `force=True` parameter can be used to force deletion of the files
+    regardless of server config.
+
     Args:
         preview_file (str / dict): The preview_file dict or ID.
+        force (bool): Whether to force deletion of the files linked to the
+            preview file in storage.
     """
     preview_file = normalize_model_parameter(preview_file)
     params = {}
@@ -166,12 +201,14 @@ def remove_preview_file(preview_file, force=False, client=default):
 
 
 @cache
-def get_all_preview_files_for_task(task, client=default):
+def get_all_preview_files_for_task(
+    task: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Retrieves all the preview files for a given task.
 
     Args:
-        task (str, id): Target task
+        task (str / dict): Target task, as ID string or model dict.
     """
     task = normalize_model_parameter(task)
     return raw.fetch_all(
@@ -180,12 +217,14 @@ def get_all_preview_files_for_task(task, client=default):
 
 
 @cache
-def get_all_attachment_files_for_task(task, client=default):
+def get_all_attachment_files_for_task(
+    task: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Retrieves all the attachment files for a given task.
 
     Args:
-        task (str, id): Target task
+        task (str / dict): Target task, as ID string or model dict.
     """
     task = normalize_model_parameter(task)
     return raw.fetch_all(
@@ -194,14 +233,14 @@ def get_all_attachment_files_for_task(task, client=default):
 
 
 def all_output_files_for_entity(
-    entity,
-    output_type=None,
-    task_type=None,
-    name=None,
-    representation=None,
-    file_status=None,
-    client=default,
-):
+    entity: str | dict,
+    output_type: str | dict | None = None,
+    task_type: str | dict | None = None,
+    name: str | None = None,
+    representation: str | None = None,
+    file_status: str | dict | None = None,
+    client: KitsuClient = default,
+) -> list[dict]:
     """
     Args:
         entity (str / dict): The entity dict or ID.
@@ -239,15 +278,15 @@ def all_output_files_for_entity(
 
 @cache
 def all_output_files_for_asset_instance(
-    asset_instance,
-    temporal_entity=None,
-    task_type=None,
-    output_type=None,
-    name=None,
-    representation=None,
-    file_status=None,
-    client=default,
-):
+    asset_instance: str | dict,
+    temporal_entity: str | dict | None = None,
+    task_type: str | dict | None = None,
+    output_type: str | dict | None = None,
+    name: str | None = None,
+    representation: str | None = None,
+    file_status: str | dict | None = None,
+    client: KitsuClient = default,
+) -> list[dict]:
     """
     Args:
         asset_instance (str / dict): The instance dict or ID.
@@ -289,17 +328,17 @@ def all_output_files_for_asset_instance(
 
 
 def all_output_files_for_project(
-    project,
-    output_type=None,
-    task_type=None,
-    name=None,
-    representation=None,
-    file_status=None,
-    client=default,
-):
+    project: str | dict,
+    output_type: str | dict | None = None,
+    task_type: str | dict | None = None,
+    name: str | None = None,
+    representation: str | None = None,
+    file_status: str | dict | None = None,
+    client: KitsuClient = default,
+) -> list[dict]:
     """
     Args:
-        entity (str / dict): The entity dict or ID.
+        project (str / dict): The project dict or ID.
         output_type (str / dict): The output type dict or ID.
         task_type (str / dict): The task type dict or ID.
         name (str): The file name
@@ -335,16 +374,16 @@ def all_output_files_for_project(
 
 
 @cache
-def all_softwares(client=default):
+def all_softwares(client: KitsuClient = default) -> list[dict]:
     """
     Returns:
-        dict: Software versions listed in database.
+        list[dict]: Software versions listed in database.
     """
     return raw.fetch_all("softwares", client=client)
 
 
 @cache
-def get_software(software_id, client=default):
+def get_software(software_id: str, client: KitsuClient = default) -> dict:
     """
     Args:
         software_id (str): ID of claimed output type.
@@ -356,7 +395,9 @@ def get_software(software_id, client=default):
 
 
 @cache
-def get_software_by_name(software_name, client=default):
+def get_software_by_name(
+    software_name: str, client: KitsuClient = default
+) -> dict | None:
     """
     Args:
         software_name (str): Name of claimed output type.
@@ -367,7 +408,12 @@ def get_software_by_name(software_name, client=default):
     return raw.fetch_first("softwares", {"name": software_name}, client=client)
 
 
-def new_software(name, short_name, file_extension, client=default):
+def new_software(
+    name: str,
+    short_name: str,
+    file_extension: str,
+    client: KitsuClient = default,
+) -> dict:
     """
     Create a new software in datatabase.
 
@@ -393,23 +439,23 @@ def new_software(name, short_name, file_extension, client=default):
 
 @cache
 def build_working_file_path(
-    task,
-    name="main",
-    mode="working",
-    software=None,
-    revision=1,
-    sep="/",
-    client=default,
-):
+    task: str | dict,
+    name: str = "main",
+    mode: str = "working",
+    software: str | dict | None = None,
+    revision: int = 1,
+    sep: str = "/",
+    client: KitsuClient = default,
+) -> str:
     """
     From the file path template configured at the project level and arguments,
     it builds a file path location where to store related DCC file.
 
     Args:
-        task (str / id): Task related to working file.
+        task (str / dict): Task related to working file.
         name (str): Additional suffix for the working file name.
         mode (str): Allow to select a template inside the template.
-        software (str / id): Software at the origin of the file.
+        software (str / dict): Software at the origin of the file.
         revision (int): File revision.
         sep (str): OS separator.
 
@@ -433,30 +479,30 @@ def build_working_file_path(
 
 @cache
 def build_entity_output_file_path(
-    entity,
-    output_type,
-    task_type,
-    name="main",
-    mode="output",
-    representation="",
-    revision=0,
-    nb_elements=1,
-    sep="/",
-    client=default,
-):
+    entity: str | dict,
+    output_type: str | dict,
+    task_type: str | dict,
+    name: str = "main",
+    mode: str = "output",
+    representation: str = "",
+    revision: int = 0,
+    nb_elements: int = 1,
+    sep: str = "/",
+    client: KitsuClient = default,
+) -> str:
     """
     From the file path template configured at the project level and arguments,
     it builds a file path location where to store related DCC output file.
 
     Args:
-        entity (str / id): Entity for which an output file is needed.
-        output_type (str / id): Output type of the generated file.
-        task_type (str / id): Task type related to output file.
+        entity (str / dict): Entity for which an output file is needed.
+        output_type (str / dict): Output type of the generated file.
+        task_type (str / dict): Task type related to output file.
         name (str): Additional suffix for the working file name.
         mode (str): Allow to select a template inside the template.
         representation (str): Allow to select a template inside the template.
         revision (int): File revision.
-        nb_elements (str): To represent an image sequence, the amount of file is
+        nb_elements (int): To represent an image sequence, the amount of file is
                            needed.
         sep (str): OS separator.
 
@@ -489,32 +535,32 @@ def build_entity_output_file_path(
 
 @cache
 def build_asset_instance_output_file_path(
-    asset_instance,
-    temporal_entity,
-    output_type,
-    task_type,
-    name="main",
-    representation="",
-    mode="output",
-    revision=0,
-    nb_elements=1,
-    sep="/",
-    client=default,
-):
+    asset_instance: str | dict,
+    temporal_entity: str | dict,
+    output_type: str | dict,
+    task_type: str | dict,
+    name: str = "main",
+    representation: str = "",
+    mode: str = "output",
+    revision: int = 0,
+    nb_elements: int = 1,
+    sep: str = "/",
+    client: KitsuClient = default,
+) -> str:
     """
     From the file path template configured at the project level and arguments,
     it builds a file path location where to store related DCC output file.
 
     Args:
-        asset_instance_id entity (str / id): Asset instance for which a file
+        asset_instance_id entity (str / dict): Asset instance for which a file
         is required.
-        temporal entity (str / id): Temporal entity scene or shot in which
+        temporal entity (str / dict): Temporal entity scene or shot in which
         the asset instance appeared.
-        output_type (str / id): Output type of the generated file.
-        task_type (str / id): Task type related to output file.
+        output_type (str / dict): Output type of the generated file.
+        task_type (str / dict): Task type related to output file.
         name (str): Additional suffix for the working file name.
-        mode (str): Allow to select a template inside the template.
         representation (str): Allow to select a template inside the template.
+        mode (str): Allow to select a template inside the template.
         revision (int): File revision.
         nb_elements (str): To represent an image sequence, the amount of file is
                            needed.
@@ -551,28 +597,28 @@ def build_asset_instance_output_file_path(
 
 
 def new_working_file(
-    task,
-    name="main",
-    mode="working",
-    software=None,
-    comment="",
-    person=None,
-    revision=0,
-    sep="/",
-    client=default,
-):
+    task: str | dict,
+    name: str = "main",
+    mode: str = "working",
+    software: str | dict | None = None,
+    comment: str = "",
+    person: str | dict | None = None,
+    revision: int = 0,
+    sep: str = "/",
+    client: KitsuClient = default,
+) -> dict:
     """
     Create a new working_file for given task. It generates and store the
     expected path for given task and options. It sets a revision number
     (last revision + 1).
 
     Args:
-        task (str / id): Task related to working file.
+        task (str / dict): Task related to working file.
         name (str): Additional suffix for the working file name.
         mode (str): Allow to select a template inside the template.
-        software (str / id): Software at the origin of the file.
+        software (str / dict): Software at the origin of the file.
         comment (str): Comment related to created revision.
-        person (str / id): Author of the file.
+        person (str / dict): Author of the file.
         revision (int): File revision.
         sep (str): OS separator.
 
@@ -600,38 +646,38 @@ def new_working_file(
 
 
 def new_entity_output_file(
-    entity,
-    output_type,
-    task_type,
-    comment,
-    working_file=None,
-    person=None,
-    name="main",
-    mode="output",
-    revision=0,
-    nb_elements=1,
-    representation="",
-    sep="/",
-    file_status_id=None,
-    client=default,
-):
+    entity: str | dict,
+    output_type: str | dict,
+    task_type: str | dict,
+    comment: str,
+    working_file: str | dict | None = None,
+    person: str | dict | None = None,
+    name: str = "main",
+    mode: str = "output",
+    revision: int = 0,
+    nb_elements: int = 1,
+    representation: str = "",
+    sep: str = "/",
+    file_status_id: str | None = None,
+    client: KitsuClient = default,
+) -> dict:
     """
     Create a new output file for given entity, task type and output type.
     It generates and store the expected path and sets a revision number
     (last revision + 1).
 
     Args:
-        entity (str / id): Entity for which an output file is needed.
-        output_type (str / id): Output type of the generated file.
-        task_type (str / id): Task type related to output file.
+        entity (str / dict): Entity for which an output file is needed.
+        output_type (str / dict): Output type of the generated file.
+        task_type (str / dict): Task type related to output file.
         comment (str): Comment related to created revision.
-        working_file (str / id): Working file which is the source of the
+        working_file (str / dict): Working file which is the source of the
         generated file.
-        person (str / id): Author of the file.
+        person (str / dict): Author of the file.
         name (str): Additional suffix for the working file name.
         mode (str): Allow to select a template inside the template.
         revision (int): File revision.
-        nb_elements (str): To represent an image sequence, the amount of file is
+        nb_elements (int): To represent an image sequence, the amount of file is
                            needed.
         representation (str): Differientate file extensions. It can be useful
         to build folders based on extensions like abc, jpg, etc.
@@ -639,7 +685,7 @@ def new_entity_output_file(
         file_status_id (id): The id of the file status to set at creation
 
     Returns:
-        Created output file.
+        dict: Created output file.
     """
     entity = normalize_model_parameter(entity)
     output_type = normalize_model_parameter(output_type)
@@ -671,42 +717,45 @@ def new_entity_output_file(
 
 
 def new_asset_instance_output_file(
-    asset_instance,
-    temporal_entity,
-    output_type,
-    task_type,
-    comment,
-    name="master",
-    mode="output",
-    working_file=None,
-    person=None,
-    revision=0,
-    nb_elements=1,
-    representation="",
-    sep="/",
-    file_status_id=None,
-    client=default,
-):
+    asset_instance: str | dict,
+    temporal_entity: str | dict,
+    output_type: str | dict,
+    task_type: str | dict,
+    comment: str,
+    name: str = "master",
+    mode: str = "output",
+    working_file: str | dict | None = None,
+    person: str | dict | None = None,
+    revision: int = 0,
+    nb_elements: int = 1,
+    representation: str = "",
+    sep: str = "/",
+    file_status_id: str | dict | None = None,
+    client: KitsuClient = default,
+) -> dict:
     """
     Create a new output file for given asset instance, temporal entity, task
     type and output type.  It generates and store the expected path and sets a
     revision number (last revision + 1).
 
     Args:
-        entity (str / id): Entity for which an output file is needed.
-        output_type (str / id): Output type of the generated file.
-        task_type (str / id): Task type related to output file.
+        asset_instance (str / dict): Asset instance for which an output file
+            is needed.
+        temporal_entity (str / dict): Temporal entity for which an output file
+            is needed.
+        output_type (str / dict): Output type of the generated file.
+        task_type (str / dict): Task type related to output file.
         comment (str): Comment related to created revision.
-        working_file (str / id): Working file which is the source of the
-    generated file.
-        person (str / id): Author of the file.
+        working_file (str / dict): Working file which is the source of the
+            generated file.
+        person (str / dict): Author of the file.
         name (str): Additional suffix for the working file name.
         mode (str): Allow to select a template inside the template.
         revision (int): File revision.
-        nb_elements (str): To represent an image sequence, the amount of file
-    needed.
-        representation (str): Differientate file extensions. It can be useful
-    to build folders based on extensions like abc, jpg, cetc.
+        nb_elements (int): To represent an image sequence, the amount of file
+            needed.
+        representation (str): Differentiate file extensions. It can be useful
+            to build folders based on extensions like abc, jpg, cetc.
         sep (str): OS separator.
         file_status_id (id): The id of the file status to set at creation
 
@@ -747,19 +796,26 @@ def new_asset_instance_output_file(
 
 
 def get_next_entity_output_revision(
-    entity, output_type, task_type, name="main", client=default
-):
+    entity: str | dict,
+    output_type: str | dict,
+    task_type: str | dict,
+    name: str = "main",
+    client: KitsuClient = default,
+) -> int:
     """
     Args:
         entity (str / dict): The entity dict or ID.
         output_type (str / dict): The entity dict or ID.
         task_type (str / dict): The entity dict or ID.
+        name (str): Get version for output file with the given name.
 
     Returns:
-        int: Next revision of ouput files available for given entity, output
+        int: Next revision of output files available for given entity, output
         type and task type.
     """
     entity = normalize_model_parameter(entity)
+    output_type = normalize_model_parameter(output_type)
+    task_type = normalize_model_parameter(task_type)
     path = "data/entities/%s/output-files/next-revision" % entity["id"]
     data = {
         "name": name,
@@ -771,13 +827,13 @@ def get_next_entity_output_revision(
 
 
 def get_next_asset_instance_output_revision(
-    asset_instance,
-    temporal_entity,
-    output_type,
-    task_type,
-    name="master",
-    client=default,
-):
+    asset_instance: str | dict,
+    temporal_entity: str | dict,
+    output_type: str | dict,
+    task_type: str | dict,
+    name: str = "master",
+    client: KitsuClient = default,
+) -> int:
     """
     Args:
         asset_instance (str / dict): The asset instance dict or ID.
@@ -806,14 +862,18 @@ def get_next_asset_instance_output_revision(
 
 
 def get_last_entity_output_revision(
-    entity, output_type, task_type, name="master", client=default
-):
+    entity: str | dict,
+    output_type: str | dict,
+    task_type: str | dict,
+    name: str = "master",
+    client: KitsuClient = default,
+) -> int:
     """
     Args:
-        entity (str / dict, client=default): The entity dict or ID.
-        output_type (str / dict, client=default): The entity dict or ID.
-        task_type (str / dict, client=default): The entity dict or ID.
-        name (str, client=default): The output name
+        entity (str / dict): The entity dict or ID.
+        output_type (str / dict): The entity dict or ID.
+        task_type (str / dict): The entity dict or ID.
+        name (str): The output name
 
     Returns:
         int: Last revision of ouput files for given entity, output type and task
@@ -831,13 +891,13 @@ def get_last_entity_output_revision(
 
 
 def get_last_asset_instance_output_revision(
-    asset_instance,
-    temporal_entity,
-    output_type,
-    task_type,
-    name="master",
-    client=default,
-):
+    asset_instance: str | dict,
+    temporal_entity: str | dict,
+    output_type: str | dict,
+    task_type: str | dict,
+    name: str = "master",
+    client: KitsuClient = default,
+) -> int:
     """
     Generate last output revision for given asset instance.
     """
@@ -860,14 +920,14 @@ def get_last_asset_instance_output_revision(
 
 @cache
 def get_last_output_files_for_entity(
-    entity,
-    output_type=None,
-    task_type=None,
-    name=None,
-    representation=None,
-    file_status=None,
-    client=default,
-):
+    entity: str | dict,
+    output_type: str | dict | None = None,
+    task_type: str | dict | None = None,
+    name: str | None = None,
+    representation: str | None = None,
+    file_status: str | dict | None = None,
+    client: KitsuClient = default,
+) -> list[dict]:
     """
     Args:
         entity (str / dict): The entity dict or ID.
@@ -907,15 +967,15 @@ def get_last_output_files_for_entity(
 
 @cache
 def get_last_output_files_for_asset_instance(
-    asset_instance,
-    temporal_entity,
-    task_type=None,
-    output_type=None,
-    name=None,
-    representation=None,
-    file_status=None,
-    client=default,
-):
+    asset_instance: str | dict,
+    temporal_entity: str | dict,
+    task_type: str | dict | None = None,
+    output_type: str | dict | None = None,
+    name: str | None = None,
+    representation: str | None = None,
+    file_status: str | dict | None = None,
+    client: KitsuClient = default,
+) -> list[dict]:
     """
     Args:
         asset_instance (str / dict): The asset instance dict or ID.
@@ -959,7 +1019,9 @@ def get_last_output_files_for_asset_instance(
 
 
 @cache
-def get_working_files_for_task(task, client=default):
+def get_working_files_for_task(
+    task: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Args:
         task (str / dict): The task dict or the task ID.
@@ -973,7 +1035,9 @@ def get_working_files_for_task(task, client=default):
 
 
 @cache
-def get_last_working_files(task, client=default):
+def get_last_working_files(
+    task: str | dict, client: KitsuClient = default
+) -> dict:
     """
     Args:
         task (str / dict): The task dict or the task ID.
@@ -988,7 +1052,9 @@ def get_last_working_files(task, client=default):
 
 
 @cache
-def get_last_working_file_revision(task, name="main", client=default):
+def get_last_working_file_revision(
+    task: str | dict, name: str = "main", client: KitsuClient = default
+) -> dict:
     """
     Args:
         task (str / dict): The task dict or the task ID.
@@ -996,7 +1062,7 @@ def get_last_working_file_revision(task, name="main", client=default):
 
     Returns:
         dict: Last revisions stored in the API for given task and given file
-        name suffx.
+        name suffix.
     """
     task = normalize_model_parameter(task)
     path = "data/tasks/%s/working-files/last-revisions" % task["id"]
@@ -1005,7 +1071,9 @@ def get_last_working_file_revision(task, name="main", client=default):
 
 
 @cache
-def get_working_file(working_file_id, client=default):
+def get_working_file(
+    working_file_id: str, client: KitsuClient = default
+) -> dict:
     """
     Args:
         working_file_id (str): ID of claimed working file.
@@ -1016,7 +1084,9 @@ def get_working_file(working_file_id, client=default):
     return raw.fetch_one("working-files", working_file_id, client=client)
 
 
-def update_comment(working_file, comment, client=default):
+def update_comment(
+    working_file: str | dict, comment: str, client: KitsuClient = default
+) -> dict:
     """
     Update the file comment in database for given working file.
 
@@ -1034,7 +1104,9 @@ def update_comment(working_file, comment, client=default):
     )
 
 
-def update_modification_date(working_file, client=default):
+def update_modification_date(
+    working_file: str | dict, client: KitsuClient = default
+) -> dict:
     """
     Update modification date of given working file with current time (now).
 
@@ -1051,12 +1123,15 @@ def update_modification_date(working_file, client=default):
     )
 
 
-def update_output_file(output_file, data, client=default):
+def update_output_file(
+    output_file: str | dict, data: dict, client: KitsuClient = default
+) -> dict:
     """
     Update the data of given output file.
 
     Args:
         output_file (str / dict): The output file dict or ID.
+        data (dict): Data to update on the output file.
 
     Returns:
         dict: Modified output file
@@ -1066,7 +1141,9 @@ def update_output_file(output_file, data, client=default):
     return raw.put(path, data, client=client)
 
 
-def set_project_file_tree(project, file_tree_name, client=default):
+def set_project_file_tree(
+    project: str | dict, file_tree_name: str, client: KitsuClient = default
+) -> dict:
     """
     (Deprecated) Set given file tree template on given project. This template
     will be used to generate file paths. The template is selected from sources.
@@ -1085,7 +1162,9 @@ def set_project_file_tree(project, file_tree_name, client=default):
     return raw.post(path, data, client=client)
 
 
-def update_project_file_tree(project, file_tree, client=default):
+def update_project_file_tree(
+    project: str | dict, file_tree: dict, client: KitsuClient = default
+) -> dict:
     """
     Set given dict as file tree template on given project. This template
     will be used to generate file paths.
@@ -1103,20 +1182,29 @@ def update_project_file_tree(project, file_tree, client=default):
     return raw.put(path, data, client=client)
 
 
-def upload_working_file(working_file, file_path, client=default):
+def upload_working_file(
+    working_file: str | dict, file_path: str, client: KitsuClient = default
+) -> dict:
     """
     Save given file in working file storage.
 
     Args:
         working_file (str / dict): The working file dict or ID.
         file_path (str): Location on hard drive where to save the file.
+
+    Returns:
+        (dict): the working file model dictionary.
     """
     working_file = normalize_model_parameter(working_file)
     url_path = "/data/working-files/%s/file" % working_file["id"]
     return raw.upload(url_path, file_path, client=client)
 
 
-def download_working_file(working_file, file_path=None, client=default):
+def download_working_file(
+    working_file: str | dict,
+    file_path: str | None = None,
+    client: KitsuClient = default,
+) -> requests.Response:
     """
     Download given working file and save it at given location.
 
@@ -1137,7 +1225,9 @@ def download_working_file(working_file, file_path=None, client=default):
     )
 
 
-def download_preview_file(preview_file, file_path, client=default):
+def download_preview_file(
+    preview_file: str | dict, file_path: str, client: KitsuClient = default
+) -> requests.Response:
     """
     Download given preview file and save it at given location.
 
@@ -1152,7 +1242,9 @@ def download_preview_file(preview_file, file_path, client=default):
     )
 
 
-def get_preview_file_url(preview_file, client=default):
+def get_preview_file_url(
+    preview_file: str | dict, client: KitsuClient = default
+) -> str:
     """
     Return given preview file URL
 
@@ -1171,7 +1263,9 @@ def get_preview_file_url(preview_file, client=default):
     )
 
 
-def get_attachment_file(attachment_file_id, client=default):
+def get_attachment_file(
+    attachment_file_id: str, client: KitsuClient = default
+) -> dict:
     """
     Return attachment file object corresponding to given ID.
 
@@ -1181,7 +1275,9 @@ def get_attachment_file(attachment_file_id, client=default):
     return raw.fetch_one("attachment-files", attachment_file_id, client=client)
 
 
-def download_attachment_file(attachment_file, file_path, client=default):
+def download_attachment_file(
+    attachment_file: str | dict, file_path: str, client: KitsuClient = default
+) -> requests.Response:
     """
     Download given attachment file and save it at given location.
 
@@ -1199,7 +1295,9 @@ def download_attachment_file(attachment_file, file_path, client=default):
     )
 
 
-def download_preview_file_thumbnail(preview_file, file_path, client=default):
+def download_preview_file_thumbnail(
+    preview_file: str | dict, file_path: str, client: KitsuClient = default
+) -> requests.Response:
     """
     Download given preview file thumbnail and save it at given location.
 
@@ -1216,7 +1314,9 @@ def download_preview_file_thumbnail(preview_file, file_path, client=default):
     )
 
 
-def download_preview_file_cover(preview_file, file_path, client=default):
+def download_preview_file_cover(
+    preview_file: str | dict, file_path: str, client: KitsuClient = default
+) -> requests.Response:
     """
     Download given preview file cover and save it at given location.
     Args:
@@ -1231,9 +1331,12 @@ def download_preview_file_cover(preview_file, file_path, client=default):
     )
 
 
-def download_person_avatar(person, file_path, client=default):
+def download_person_avatar(
+    person: str | dict, file_path: str, client: KitsuClient = default
+) -> requests.Response:
     """
     Download given person's avatar and save it at given location.
+
     Args:
         person (str / dict): The person dict or ID.
         file_path (str): Location on hard drive where to save the file.
@@ -1246,13 +1349,19 @@ def download_person_avatar(person, file_path, client=default):
     )
 
 
-def upload_person_avatar(person, file_path, client=default):
+def upload_person_avatar(
+    person: str | dict, file_path: str, client: KitsuClient = default
+) -> dict[Literal["thumbnail_path"], str]:
     """
     Upload given file as person avatar.
 
     Args:
         person (str / dict): The person dict or the person ID.
         file_path (str): Path of the file to upload as avatar.
+
+    Returns:
+        dict: Dictionary with a key of 'thumbnail_path' and a value of the
+            path to the static image file, relative to the host url.
     """
     path = (
         "/pictures/thumbnails/persons/%s"
@@ -1261,9 +1370,12 @@ def upload_person_avatar(person, file_path, client=default):
     return raw.upload(path, file_path, client=client)
 
 
-def download_project_avatar(project, file_path, client=default):
+def download_project_avatar(
+    project: str | dict, file_path: str, client: KitsuClient = default
+) -> requests.Response:
     """
     Download given project's avatar and save it at given location.
+
     Args:
         project (str / dict): The project dict or ID.
         file_path (str): Location on hard drive where to save the file.
@@ -1276,13 +1388,19 @@ def download_project_avatar(project, file_path, client=default):
     )
 
 
-def upload_project_avatar(project, file_path, client=default):
+def upload_project_avatar(
+    project: str | dict, file_path: str, client: KitsuClient = default
+) -> dict[Literal["thumbnail_path"], str]:
     """
     Upload given file as project avatar.
 
     Args:
         project (str / dict): The project dict or ID.
         file_path (str): Path of the file to upload as avatar.
+
+    Returns:
+        dict: Dictionary with a key of 'thumbnail_path' and a value of the
+            path to the static image file, relative to the host url.
     """
     path = (
         "/pictures/thumbnails/projects/%s"
@@ -1291,9 +1409,12 @@ def upload_project_avatar(project, file_path, client=default):
     return raw.upload(path, file_path, client=client)
 
 
-def download_organisation_avatar(organisation, file_path, client=default):
+def download_organisation_avatar(
+    organisation: str | dict, file_path: str, client: KitsuClient = default
+) -> requests.Response:
     """
     Download given organisation's avatar and save it at given location.
+
     Args:
         organisation (str / dict): The organisation dict or ID.
         file_path (str): Location on hard drive where to save the file.
@@ -1306,13 +1427,19 @@ def download_organisation_avatar(organisation, file_path, client=default):
     )
 
 
-def upload_organisation_avatar(organisation, file_path, client=default):
+def upload_organisation_avatar(
+    organisation: str | dict, file_path: str, client: KitsuClient = default
+) -> dict[Literal["thumbnail_path"], str]:
     """
     Upload given file as organisation avatar.
 
     Args:
         organisation (str / dict): The organisation dict or ID.
         file_path (str): Path of the file to upload as avatar.
+
+    Returns:
+        dict: Dictionary with a key of 'thumbnail_path' and a value of the
+            path to the static image file, relative to the host url.
     """
     path = (
         "/pictures/thumbnails/organisations/%s"
@@ -1321,12 +1448,15 @@ def upload_organisation_avatar(organisation, file_path, client=default):
     return raw.upload(path, file_path, client=client)
 
 
-def update_preview(preview_file, data, client=default):
+def update_preview(
+    preview_file: str | dict, data: dict, client: KitsuClient = default
+) -> dict:
     """
     Update the data of given preview file.
 
     Args:
         preview_file (str / dict): The preview file dict or ID.
+        data (dict): Data to update on the prevew file.
 
     Returns:
         dict: Modified preview file
@@ -1336,9 +1466,17 @@ def update_preview(preview_file, data, client=default):
     return raw.put(path, data, client=client)
 
 
-def new_file_status(name, color, client=default):
+def new_file_status(
+    name: str, color: str, client: KitsuClient = default
+) -> dict:
     """
     Create a new file status if not existing yet.
+
+    If the file status already exists, the existing record will be returned.
+
+    Args:
+        name (str): the name of the status to create.
+        color (str): The color for the status as a Hex string, e.g "#00FF00".
     """
     data = {"name": name, "color": color}
     status = get_file_status_by_name(name, client=client)
@@ -1349,7 +1487,7 @@ def new_file_status(name, color, client=default):
 
 
 @cache
-def get_file_status(status_id, client=default):
+def get_file_status(status_id: str, client: KitsuClient = default) -> dict:
     """
     Return file status object corresponding to given ID.
 
@@ -1360,7 +1498,9 @@ def get_file_status(status_id, client=default):
 
 
 @cache
-def get_file_status_by_name(name, client=default):
+def get_file_status_by_name(
+    name: str, client: KitsuClient = default
+) -> dict | None:
     """
     Return file status object corresponding to given name
 
diff --git a/gazu/playlist.py b/gazu/playlist.py
index edd1e02..6d0f8f7 100644
--- a/gazu/playlist.py
+++ b/gazu/playlist.py
@@ -1,15 +1,22 @@
+from __future__ import annotations
+
+import requests
+
+from typing_extensions import Literal
+
 from . import client as raw
 
 from .helpers import normalize_model_parameter
 from .sorting import sort_by_name
 
 from .cache import cache
+from .client import KitsuClient
 
 default = raw.default_client
 
 
 @cache
-def all_playlists(client=default):
+def all_playlists(client: KitsuClient = default) -> list[dict]:
     """
     Returns:
         list: All playlists for all projects.
@@ -18,7 +25,9 @@ def all_playlists(client=default):
 
 
 @cache
-def all_shots_for_playlist(playlist, client=default):
+def all_shots_for_playlist(
+    playlist: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Args:
         playlist (str / dict): The playlist dict or the playlist ID.
@@ -32,10 +41,13 @@ def all_shots_for_playlist(playlist, client=default):
 
 
 @cache
-def all_playlists_for_project(project, client=default, page=1):
+def all_playlists_for_project(
+    project: str | dict, client: KitsuClient = default, page: int = 1
+) -> list[dict]:
     """
     Args:
         project (str / dict): The project dict or the project ID.
+        page (int): Page number for pagination
 
     Returns:
         list: All playlists for the given project
@@ -51,16 +63,16 @@ def all_playlists_for_project(project, client=default, page=1):
 
 
 @cache
-def all_playlists_for_episode(episode, client=default):
+def all_playlists_for_episode(
+    episode: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
-
     Args:
         episode (str / dict): The episode dict or the episode ID.
 
     Returns:
         list: All playlists for the given episode.
     """
-
     project = normalize_model_parameter(episode["project_id"])
     return sort_by_name(
         raw.fetch_all(
@@ -75,7 +87,7 @@ def all_playlists_for_episode(episode, client=default):
 
 
 @cache
-def get_playlist(playlist, client=default):
+def get_playlist(playlist: str | dict, client: KitsuClient = default) -> dict:
     """
     Args:
         playlist (str / dict): The playlist dict or the playlist ID.
@@ -83,13 +95,14 @@ def get_playlist(playlist, client=default):
     Returns:
         dict: playlist object for given id.
     """
-
     playlist = normalize_model_parameter(playlist)
     return raw.fetch_one("playlists", playlist["id"], client=client)
 
 
 @cache
-def get_playlist_by_name(project, name, client=default):
+def get_playlist_by_name(
+    project: str | dict, name: str, client: KitsuClient = default
+) -> dict | None:
     """
     Args:
         project (str / dict): The project dict or the project ID.
@@ -104,19 +117,22 @@ def get_playlist_by_name(project, name, client=default):
 
 
 def new_playlist(
-    project,
-    name,
-    episode=None,
-    for_entity="shot",
-    for_client=False,
-    client=default,
-):
+    project: str | dict,
+    name: str,
+    episode: str | dict | None = None,
+    for_entity: Literal["shot", "asset", "sequence"] = "shot",
+    for_client: bool = False,
+    client: KitsuClient = default,
+) -> dict:
     """
     Create a new playlist in the database for given project.
 
     Args:
         project (str / dict): The project dict or the project ID.
         name (str): Playlist name.
+        for_entity (str): The type of entity to include in the playlist, can
+            be one of "asset", "sequence" or "shot".
+        for_client (bool): Whether the playlist should be shared with clients.
 
     Returns:
         dict: Created playlist.
@@ -137,7 +153,7 @@ def new_playlist(
     return playlist
 
 
-def update_playlist(playlist, client=default):
+def update_playlist(playlist: dict, client: KitsuClient = default) -> dict:
     """
     Save given playlist data into the API. Metadata are fully replaced by
     the ones set on given playlist.
@@ -153,7 +169,9 @@ def update_playlist(playlist, client=default):
     )
 
 
-def get_entity_preview_files(entity, client=default):
+def get_entity_preview_files(
+    entity: str | dict, client: KitsuClient = default
+) -> dict[str, list[dict]]:
     """
     Get all preview files grouped by task type for a given entity.
 
@@ -171,8 +189,12 @@ def get_entity_preview_files(entity, client=default):
 
 
 def add_entity_to_playlist(
-    playlist, entity, preview_file=None, persist=True, client=default
-):
+    playlist: dict,
+    entity: str | dict,
+    preview_file: str | dict | None = None,
+    persist: bool = True,
+    client: KitsuClient = default,
+) -> dict:
     """
     Add an entity to the playlist, use the last uploaded preview as revision
     to review.
@@ -209,14 +231,18 @@ def add_entity_to_playlist(
 
 
 def remove_entity_from_playlist(
-    playlist, entity, persist=True, client=default
-):
+    playlist: dict,
+    entity: str | dict,
+    persist: bool = True,
+    client: KitsuClient = default,
+) -> dict:
     """
     Remove all occurences of a given entity from a playlist.
 
     Args:
         playlist (dict): Playlist object to modify
         entity (str / dict): the entity to remove or its ID
+        persist (bool): Set it to True to save the result to the API.
 
     Returns:
         dict: Updated playlist.
@@ -233,14 +259,20 @@ def remove_entity_from_playlist(
 
 
 def update_entity_preview(
-    playlist, entity, preview_file, persist=True, client=default
-):
+    playlist: dict,
+    entity: str | dict,
+    preview_file: str | dict,
+    persist: bool = True,
+    client: KitsuClient = default,
+) -> dict:
     """
-    Remove all occurences of a given entity from a playlist.
+    Update the preview file linked to a given entity in a playlist.
 
     Args:
-        playlist (dict): Playlist object to modify
-        entity (str / dict): the entity to add or its ID
+        playlist (dict): Playlist object to modify.
+        entity (str / dict): The entity to update the preview file for.
+        preview_file (str / dict): The new preview file to set for the entity.
+        persist (bool): Set it to True to save the result to the API.
 
     Returns:
         dict: Updated playlist.
@@ -256,12 +288,14 @@ def update_entity_preview(
 
 
 @cache
-def delete_playlist(playlist, client=default):
+def delete_playlist(
+    playlist: str | dict, client: KitsuClient = default
+) -> str:
     """
     Delete a playlist.
 
     Args:
-        playlist (dict / ID): The playlist dict or id.
+        playlist (str / dict): The playlist dict or id.
 
     Returns:
         Response: Request response object.
@@ -271,12 +305,14 @@ def delete_playlist(playlist, client=default):
 
 
 @cache
-def get_entity_previews(playlist, client=default):
+def get_entity_previews(
+    playlist: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get entity previews for a playlist.
 
     Args:
-        playlist (dict / ID): The playlist dict or id.
+        playlist (str / dict): The playlist dict or id.
 
     Returns:
         list: Entity previews for the playlist.
@@ -288,29 +324,32 @@ def get_entity_previews(playlist, client=default):
 
 
 @cache
-def get_build_job(build_job, client=default):
+def get_build_job(
+    build_job: str | dict, client: KitsuClient = default
+) -> dict:
     """
     Get a build job.
 
     Args:
-        build_job (dict / ID): The build job dict or id.
+        build_job (str / dict): The build job dict or id.
 
     Returns:
         dict: Build job information.
     """
     build_job = normalize_model_parameter(build_job)
-    return raw.fetch_one("playlists/build-jobs", build_job["id"], client=client)
+    return raw.fetch_one(
+        "playlists/build-jobs", build_job["id"], client=client
+    )
 
 
-def remove_build_job(build_job, client=default):
+def remove_build_job(
+    build_job: str | dict, client: KitsuClient = default
+) -> str:
     """
     Delete a build job.
 
     Args:
-        build_job (dict / ID): The build job dict or id.
-
-    Returns:
-        Response: Request response object.
+        build_job (str / dict): The build job dict or id.
     """
     build_job = normalize_model_parameter(build_job)
     return raw.delete(
@@ -319,12 +358,14 @@ def remove_build_job(build_job, client=default):
 
 
 @cache
-def all_build_jobs_for_project(project, client=default):
+def all_build_jobs_for_project(
+    project: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get all build jobs for a project.
 
     Args:
-        project (dict / ID): The project dict or id.
+        project (str / dict): The project dict or id.
 
     Returns:
         list: All build jobs for the project.
@@ -335,12 +376,14 @@ def all_build_jobs_for_project(project, client=default):
     )
 
 
-def build_playlist_movie(playlist, client=default):
+def build_playlist_movie(
+    playlist: str | dict, client: KitsuClient = default
+) -> dict:
     """
     Build a movie for a playlist.
 
     Args:
-        playlist (dict / ID): The playlist dict or id.
+        playlist (str / dict): The playlist dict or id.
 
     Returns:
         dict: Build job information.
@@ -351,13 +394,18 @@ def build_playlist_movie(playlist, client=default):
     )
 
 
-def download_playlist_build(playlist, build_job, file_path, client=default):
+def download_playlist_build(
+    playlist: str | dict,
+    build_job: str | dict,
+    file_path: str,
+    client: KitsuClient = default,
+) -> requests.Response:
     """
     Download a playlist build.
 
     Args:
-        playlist (dict / ID): The playlist dict or id.
-        build_job (dict / ID): The build job dict or id.
+        playlist (str / dict): The playlist dict or id.
+        build_job (str / dict): The build job dict or id.
         file_path (str): The location to store the file on the hard drive.
 
     Returns:
@@ -372,12 +420,14 @@ def download_playlist_build(playlist, build_job, file_path, client=default):
     return raw.download(path, file_path, client=client)
 
 
-def download_playlist_zip(playlist, file_path, client=default):
+def download_playlist_zip(
+    playlist: str | dict, file_path: str, client: KitsuClient = default
+) -> requests.Response:
     """
     Download a playlist as a zip file.
 
     Args:
-        playlist (dict / ID): The playlist dict or id.
+        playlist (str / dict): The playlist dict or id.
         file_path (str): The location to store the file on the hard drive.
 
     Returns:
@@ -388,12 +438,14 @@ def download_playlist_zip(playlist, file_path, client=default):
     return raw.download(path, file_path, client=client)
 
 
-def generate_temp_playlist(project, data, client=default):
+def generate_temp_playlist(
+    project: str | dict, data: dict, client: KitsuClient = default
+) -> dict:
     """
     Generate a temporary playlist.
 
     Args:
-        project (dict / ID): The project dict or id.
+        project (str / dict): The project dict or id.
         data (dict): Playlist generation data.
 
     Returns:
@@ -405,12 +457,14 @@ def generate_temp_playlist(project, data, client=default):
     )
 
 
-def notify_clients_playlist_ready(playlist, client=default):
+def notify_clients_playlist_ready(
+    playlist: str | dict, client: KitsuClient = default
+) -> dict:
     """
     Notify clients that a playlist is ready.
 
     Args:
-        playlist (dict / ID): The playlist dict or id.
+        playlist (str / dict): The playlist dict or id.
 
     Returns:
         dict: Notification response.
diff --git a/gazu/project.py b/gazu/project.py
index 71e17f8..c5d5444 100644
--- a/gazu/project.py
+++ b/gazu/project.py
@@ -1,7 +1,12 @@
+from __future__ import annotations
+
+from typing_extensions import Literal  # Python 3.7 compatibility.
+
 from . import client as raw
 
 from .sorting import sort_by_name
 from .cache import cache
+from .client import KitsuClient
 from .helpers import (
     normalize_model_parameter,
     normalize_list_of_models_for_links,
@@ -11,7 +16,7 @@
 
 
 @cache
-def all_project_status(client=default):
+def all_project_status(client: KitsuClient = default) -> list[dict]:
     """
     Returns:
         list: Project status listed in database.
@@ -20,7 +25,9 @@ def all_project_status(client=default):
 
 
 @cache
-def get_project_status_by_name(project_status_name, client=default):
+def get_project_status_by_name(
+    project_status_name: str, client: KitsuClient = default
+) -> dict | None:
     """
     Args:
         project_status_name (str): Name of claimed project status.
@@ -34,7 +41,7 @@ def get_project_status_by_name(project_status_name, client=default):
 
 
 @cache
-def all_projects(client=default):
+def all_projects(client: KitsuClient = default) -> list[dict]:
     """
     Returns:
         list: Projects stored in the database.
@@ -43,7 +50,7 @@ def all_projects(client=default):
 
 
 @cache
-def all_open_projects(client=default):
+def all_open_projects(client: KitsuClient = default) -> list[dict]:
     """
     Returns:
         Open projects stored in the database.
@@ -52,7 +59,7 @@ def all_open_projects(client=default):
 
 
 @cache
-def get_project(project_id, client=default):
+def get_project(project_id: str, client: KitsuClient = default) -> dict:
     """
     Args:
         project_id (str): ID of claimed project.
@@ -64,7 +71,9 @@ def get_project(project_id, client=default):
 
 
 @cache
-def get_project_url(project, section="assets", client=default):
+def get_project_url(
+    project: str | dict, section: str = "assets", client: KitsuClient = default
+) -> str:
     """
     Args:
         project (str / dict): The project dict or the project ID.
@@ -83,7 +92,9 @@ def get_project_url(project, section="assets", client=default):
 
 
 @cache
-def get_project_by_name(project_name, client=default):
+def get_project_by_name(
+    project_name: str, client: KitsuClient = default
+) -> dict | None:
     """
     Args:
         project_name (str): Name of claimed project.
@@ -95,15 +106,15 @@ def get_project_by_name(project_name, client=default):
 
 
 def new_project(
-    name,
-    production_type="short",
-    team=[],
-    asset_types=[],
-    task_statuses=[],
-    task_types=[],
-    production_style="2d3d",
-    client=default,
-):
+    name: str,
+    production_type: str = "short",
+    team: list = [],
+    asset_types: list = [],
+    task_statuses: list = [],
+    task_types: list = [],
+    production_style: str = "2d3d",
+    client: KitsuClient = default,
+) -> dict:
     """
     Creates a new project.
 
@@ -139,7 +150,9 @@ def new_project(
     return project
 
 
-def remove_project(project, force=False, client=default):
+def remove_project(
+    project: str | dict, force: bool = False, client: KitsuClient = default
+) -> str:
     """
     Remove given project from database. (Prior to do that, make sure, there
     is no asset or shot left).
@@ -154,7 +167,7 @@ def remove_project(project, force=False, client=default):
     return raw.delete(path, client=client)
 
 
-def update_project(project, client=default):
+def update_project(project: dict, client: KitsuClient = default) -> dict:
     """
     Save given project data into the API. Metadata are fully replaced by the
     ones set on given project.
@@ -182,7 +195,9 @@ def update_project(project, client=default):
     return raw.put("data/projects/%s" % project["id"], project, client=client)
 
 
-def update_project_data(project, data={}, client=default):
+def update_project_data(
+    project: str | dict, data: dict = {}, client: KitsuClient = default
+) -> dict:
     """
     Update the metadata for the provided project. Keys that are not provided
     are not changed.
@@ -202,7 +217,7 @@ def update_project_data(project, data={}, client=default):
     return update_project(project, client=client)
 
 
-def close_project(project, client=default):
+def close_project(project: str | dict, client: KitsuClient = default) -> dict:
     """
     Closes the provided project.
 
@@ -223,7 +238,9 @@ def close_project(project, client=default):
     return project
 
 
-def add_asset_type(project, asset_type, client=default):
+def add_asset_type(
+    project: str | dict, asset_type: str | dict, client: KitsuClient = default
+) -> dict:
     project = normalize_model_parameter(project)
     asset_type = normalize_model_parameter(asset_type)
     data = {"asset_type_id": asset_type["id"]}
@@ -234,7 +251,12 @@ def add_asset_type(project, asset_type, client=default):
     )
 
 
-def add_task_type(project, task_type, priority, client=default):
+def add_task_type(
+    project: str | dict,
+    task_type: str | dict,
+    priority: int,
+    client: KitsuClient = default,
+) -> dict:
     project = normalize_model_parameter(project)
     task_type = normalize_model_parameter(task_type)
     data = {"task_type_id": task_type["id"], "priority": priority}
@@ -245,7 +267,9 @@ def add_task_type(project, task_type, priority, client=default):
     )
 
 
-def add_task_status(project, task_status, client=default):
+def add_task_status(
+    project: str | dict, task_status: str | dict, client: KitsuClient = default
+) -> dict:
     project = normalize_model_parameter(project)
     task_status = normalize_model_parameter(task_status)
     data = {"task_status_id": task_status["id"]}
@@ -257,15 +281,15 @@ def add_task_status(project, task_status, client=default):
 
 
 def add_metadata_descriptor(
-    project,
-    name,
-    entity_type,
-    data_type="string",
-    choices=[],
-    for_client=False,
-    departments=[],
-    client=default,
-):
+    project: str | dict,
+    name: str,
+    entity_type: str,
+    data_type: str = "string",
+    choices: list[str] = [],
+    for_client: bool = False,
+    departments: list[str | dict] = [],
+    client: KitsuClient = default,
+) -> dict:
     """
     Create a new metadata descriptor for a project.
 
@@ -296,7 +320,11 @@ def add_metadata_descriptor(
     )
 
 
-def get_metadata_descriptor(project, metadata_descriptor_id, client=default):
+def get_metadata_descriptor(
+    project: str | dict,
+    metadata_descriptor_id: str,
+    client: KitsuClient = default,
+) -> dict:
     """
     Retrieve a the metadata descriptor matching given ID.
 
@@ -316,13 +344,15 @@ def get_metadata_descriptor(project, metadata_descriptor_id, client=default):
     )
 
 
-def get_metadata_descriptor_by_field_name(project, field_name, client=default):
+def get_metadata_descriptor_by_field_name(
+    project: str | dict, field_name: str, client: KitsuClient = default
+) -> dict | None:
     """
-    Get a metadata descriptor matchind given project and name.
+    Get a metadata descriptor matching the given project and name.
 
     Args:
         project (dict / ID): The project dict or id.
-        metadata_descriptor_id (dict / ID): The metadata descriptor dict or id.
+        field_name (str): The name of the metadata field.
 
     Returns:
         dict: The metadata descriptor matchind the ID.
@@ -338,7 +368,9 @@ def get_metadata_descriptor_by_field_name(project, field_name, client=default):
     )
 
 
-def all_metadata_descriptors(project, client=default):
+def all_metadata_descriptors(
+    project: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get all the metadata descriptors.
 
@@ -355,7 +387,11 @@ def all_metadata_descriptors(project, client=default):
     )
 
 
-def update_metadata_descriptor(project, metadata_descriptor, client=default):
+def update_metadata_descriptor(
+    project: str | dict,
+    metadata_descriptor: dict,
+    client: KitsuClient = default,
+) -> dict:
     """
     Update a metadata descriptor.
 
@@ -383,8 +419,11 @@ def update_metadata_descriptor(project, metadata_descriptor, client=default):
 
 
 def remove_metadata_descriptor(
-    project, metadata_descriptor_id, force=False, client=default
-):
+    project: str | dict,
+    metadata_descriptor_id: str | dict,
+    force: bool = False,
+    client: KitsuClient = default,
+) -> str:
     """
     Remove a metadata descriptor.
 
@@ -405,24 +444,32 @@ def remove_metadata_descriptor(
     )
 
 
-def get_team(project, client=default):
+def get_team(project: str | dict, client: KitsuClient = default) -> list[dict]:
     """
     Get team for project.
 
     Args:
         project (dict / ID): The project dict or id.
+
+    Returns:
+        list[dict]: The list of user dicts that are part of the project team.
     """
     project = normalize_model_parameter(project)
     return raw.fetch_all("projects/%s/team" % project["id"], client=client)
 
 
-def add_person_to_team(project, person, client=default):
+def add_person_to_team(
+    project: str | dict, person: str | dict, client: KitsuClient = default
+) -> dict:
     """
     Add a person to the team project.
 
     Args:
         project (dict / ID): The project dict or id.
         person (dict / ID): The person dict or id.
+
+    Returns:
+        dict: The project dictionary.
     """
     project = normalize_model_parameter(project)
     person = normalize_model_parameter(person)
@@ -432,7 +479,9 @@ def add_person_to_team(project, person, client=default):
     )
 
 
-def remove_person_from_team(project, person, client=default):
+def remove_person_from_team(
+    project: str | dict, person: str | dict, client: KitsuClient = default
+) -> str:
     """
     Remove a person from the team project.
 
@@ -449,7 +498,9 @@ def remove_person_from_team(project, person, client=default):
 
 
 @cache
-def get_project_task_types(project, client=default):
+def get_project_task_types(
+    project: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get task types configured for a project.
 
@@ -466,7 +517,9 @@ def get_project_task_types(project, client=default):
 
 
 @cache
-def get_project_task_statuses(project, client=default):
+def get_project_task_statuses(
+    project: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get task statuses configured for a project.
 
@@ -483,7 +536,9 @@ def get_project_task_statuses(project, client=default):
 
 
 @cache
-def all_status_automations(project, client=default):
+def all_status_automations(
+    project: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get status automations configured for a project.
 
@@ -500,13 +555,21 @@ def all_status_automations(project, client=default):
     )
 
 
-def add_status_automation(project, automation, client=default):
+def add_status_automation(
+    project: str | dict,
+    automation: dict[Literal["status_automation_id"], str],
+    client: KitsuClient = default,
+) -> dict:
     """
     Add a status automation to the project.
 
     Args:
         project (dict / ID): The project dict or id.
-        automation (dict): The automation payload (e.g. from/to status, task_type, rules).
+        automation (dict): A dictionary with a key of "status_automation_id" and
+            value of the automation ID.
+
+    Returns:
+        dict: The project dictionary.
     """
     project = normalize_model_parameter(project)
     return raw.post(
@@ -516,7 +579,9 @@ def add_status_automation(project, automation, client=default):
     )
 
 
-def remove_status_automation(project, automation, client=default):
+def remove_status_automation(
+    project: str | dict, automation: str | dict, client: KitsuClient = default
+) -> str:
     """
     Remove a status automation from the project.
 
@@ -534,7 +599,9 @@ def remove_status_automation(project, automation, client=default):
 
 
 @cache
-def get_preview_background_files(project, client=default):
+def get_preview_background_files(
+    project: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get preview background files configured for a project.
 
@@ -543,11 +610,16 @@ def get_preview_background_files(project, client=default):
     """
     project = normalize_model_parameter(project)
     return raw.fetch_all(
-        "projects/%s/settings/preview-background-files" % project["id"], client=client
+        "projects/%s/settings/preview-background-files" % project["id"],
+        client=client,
     )
 
 
-def add_preview_background_file(project, background_file, client=default):
+def add_preview_background_file(
+    project: str | dict,
+    background_file: dict[Literal["preview_background_file_id"], str],
+    client: KitsuClient = default,
+) -> dict:
     """
     Add a preview background file to a project.
 
@@ -558,7 +630,7 @@ def add_preview_background_file(project, background_file, client=default):
         project (dict / ID): The project dict or id.
         background_file (dict): A dict with a key of "preview_background_file_id"
             and value of the ID of the preview background to add.
-    
+
     Returns:
         (dict): The project dictionary.
     """
@@ -570,7 +642,11 @@ def add_preview_background_file(project, background_file, client=default):
     )
 
 
-def remove_preview_background_file(project, background_file, client=default):
+def remove_preview_background_file(
+    project: str | dict,
+    background_file: str | dict,
+    client: KitsuClient = default,
+) -> str:
     """
     Remove a preview background file from a project.
 
@@ -588,7 +664,9 @@ def remove_preview_background_file(project, background_file, client=default):
 
 
 @cache
-def get_milestones(project, client=default):
+def get_milestones(
+    project: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get production milestones for a project.
 
@@ -602,7 +680,9 @@ def get_milestones(project, client=default):
 
 
 @cache
-def get_project_quotas(project, client=default):
+def get_project_quotas(
+    project: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get quotas for a project.
 
@@ -610,13 +690,13 @@ def get_project_quotas(project, client=default):
         project (dict / ID): The project dict or id.
     """
     project = normalize_model_parameter(project)
-    return raw.fetch_all(
-        "projects/%s/quotas" % project["id"], client=client
-    )
+    return raw.fetch_all("projects/%s/quotas" % project["id"], client=client)
 
 
 @cache
-def get_project_person_quotas(project, person, client=default):
+def get_project_person_quotas(
+    project: str | dict, person: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get quotas for a person within a project.
 
@@ -634,7 +714,9 @@ def get_project_person_quotas(project, person, client=default):
 
 
 @cache
-def get_budgets(project, client=default):
+def get_budgets(
+    project: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get budgets for a project.
 
@@ -646,15 +728,15 @@ def get_budgets(project, client=default):
 
 
 def create_budget(
-    project,
-    name,
-    description=None,
-    currency=None,
-    start_date=None,
-    end_date=None,
-    amount=None,
-    client=default,
-):
+    project: str | dict,
+    name: str,
+    description: str | None = None,
+    currency: str | None = None,
+    start_date: str | None = None,
+    end_date: str | None = None,
+    amount: int | float | None = None,
+    client: KitsuClient = default,
+) -> dict:
     """
     Create a budget for a project.
 
@@ -685,7 +767,9 @@ def create_budget(
 
 
 @cache
-def get_budget(project, budget, client=default):
+def get_budget(
+    project: str | dict, budget: str | dict, client: KitsuClient = default
+) -> dict:
     """
     Get a specific budget.
 
@@ -700,7 +784,12 @@ def get_budget(project, budget, client=default):
     )
 
 
-def update_budget(project, budget, data, client=default):
+def update_budget(
+    project: str | dict,
+    budget: str | dict,
+    data: dict,
+    client: KitsuClient = default,
+) -> dict:
     """
     Update a specific budget.
 
@@ -718,7 +807,9 @@ def update_budget(project, budget, data, client=default):
     )
 
 
-def remove_budget(project, budget, client=default):
+def remove_budget(
+    project: str | dict, budget: str | dict, client: KitsuClient = default
+) -> str:
     """
     Delete a specific budget.
 
@@ -735,7 +826,9 @@ def remove_budget(project, budget, client=default):
 
 
 @cache
-def get_budget_entries(project, budget, client=default):
+def get_budget_entries(
+    project: str | dict, budget: str | dict, client: KitsuClient = default
+) -> list[dict]:
     """
     Get entries for a specific budget.
 
@@ -752,17 +845,17 @@ def get_budget_entries(project, budget, client=default):
 
 
 def create_budget_entry(
-    project,
-    budget,
-    name,
-    date=None,
-    amount=None,
-    quantity=None,
-    unit_price=None,
-    description=None,
-    category=None,
-    client=default,
-):
+    project: str | dict,
+    budget: str | dict,
+    name: str,
+    date: str | None = None,
+    amount: int | float | None = None,
+    quantity: int | float | None = None,
+    unit_price: int | float | None = None,
+    description: str | None = None,
+    category: str | None = None,
+    client: KitsuClient = default,
+) -> dict:
     """
     Create a budget entry for a specific budget.
 
@@ -793,15 +886,19 @@ def create_budget_entry(
     if category is not None:
         data["category"] = category
     return raw.post(
-        "data/projects/%s/budgets/%s/entries"
-        % (project["id"], budget["id"]),
+        "data/projects/%s/budgets/%s/entries" % (project["id"], budget["id"]),
         data,
         client=client,
     )
 
 
 @cache
-def get_budget_entry(project, budget, entry, client=default):
+def get_budget_entry(
+    project: str | dict,
+    budget: str | dict,
+    entry: str | dict,
+    client: KitsuClient = default,
+) -> dict:
     """
     Get a specific budget entry.
 
@@ -820,7 +917,13 @@ def get_budget_entry(project, budget, entry, client=default):
     )
 
 
-def update_budget_entry(project, budget, entry, data, client=default):
+def update_budget_entry(
+    project: str | dict,
+    budget: str | dict,
+    entry: str | dict,
+    data: dict,
+    client: KitsuClient = default,
+) -> dict:
     """
     Update a specific budget entry.
 
@@ -841,7 +944,12 @@ def update_budget_entry(project, budget, entry, data, client=default):
     )
 
 
-def remove_budget_entry(project, budget, entry, client=default):
+def remove_budget_entry(
+    project: str | dict,
+    budget: str | dict,
+    entry: str | dict,
+    client: KitsuClient = default,
+) -> str:
     """
     Delete a specific budget entry.