diff --git a/src/judge0/api.py b/src/judge0/api.py
index 92b91b1..6c08471 100644
--- a/src/judge0/api.py
+++ b/src/judge0/api.py
@@ -353,10 +353,12 @@ def async_execute(
         resolved.
     submissions : Submission or Submissions, optional
         Submission or submissions for execution.
-    source_code: str, optional
+    source_code : str, optional
         A source code of a program.
-    test_cases: TestCaseType or TestCases, optional
+    test_cases : TestCaseType or TestCases, optional
         A single test or a list of test cases
+    **kwargs : dict
+        Additional keyword arguments to pass to the Submission constructor.
 
     Returns
     -------
@@ -405,6 +407,8 @@ def sync_execute(
         A source code of a program.
     test_cases: TestCaseType or TestCases, optional
         A single test or a list of test cases
+    **kwargs : dict
+        Additional keyword arguments to pass to the Submission constructor.
 
     Returns
     -------
diff --git a/src/judge0/clients.py b/src/judge0/clients.py
index ac5af89..621b844 100644
--- a/src/judge0/clients.py
+++ b/src/judge0/clients.py
@@ -356,7 +356,19 @@ def get_submissions(
 
 
 class ATD(Client):
-    """Base class for all AllThingsDev clients."""
+    """Base class for all AllThingsDev clients.
+
+    Parameters
+    ----------
+    endpoint : str
+        Default request endpoint.
+    host_header_value : str
+        Value for the x-apihub-host header.
+    api_key : str
+        AllThingsDev API key.
+    **kwargs : dict
+        Additional keyword arguments for the base Client.
+    """
 
     API_KEY_ENV: ClassVar[str] = "JUDGE0_ATD_API_KEY"
 
@@ -376,7 +388,15 @@ def _update_endpoint_header(self, header_value):
 
 
 class ATDJudge0CE(ATD):
-    """AllThingsDev client for CE flavor."""
+    """AllThingsDev client for CE flavor.
+
+    Parameters
+    ----------
+    api_key : str
+        AllThingsDev API key.
+    **kwargs : dict
+        Additional keyword arguments for the base Client.
+    """
 
     DEFAULT_ENDPOINT: ClassVar[str] = (
         "https://judge0-ce.proxy-production.allthingsdev.co"
@@ -460,7 +480,15 @@ def get_submissions(
 
 
 class ATDJudge0ExtraCE(ATD):
-    """AllThingsDev client for Extra CE flavor."""
+    """AllThingsDev client for Extra CE flavor.
+
+    Parameters
+    ----------
+    api_key : str
+        AllThingsDev API key.
+    **kwargs : dict
+        Additional keyword arguments for the base Client.
+    """
 
     DEFAULT_ENDPOINT: ClassVar[str] = (
         "https://judge0-extra-ce.proxy-production.allthingsdev.co"
@@ -545,7 +573,19 @@ def get_submissions(
 
 
 class Rapid(Client):
-    """Base class for all RapidAPI clients."""
+    """Base class for all RapidAPI clients.
+
+    Parameters
+    ----------
+    endpoint : str
+        Default request endpoint.
+    host_header_value : str
+        Value for the x-rapidapi-host header.
+    api_key : str
+        RapidAPI API key.
+    **kwargs : dict
+        Additional keyword arguments for the base Client.
+    """
 
     API_KEY_ENV: ClassVar[str] = "JUDGE0_RAPID_API_KEY"
 
@@ -562,7 +602,15 @@ def __init__(self, endpoint, host_header_value, api_key, **kwargs):
 
 
 class RapidJudge0CE(Rapid):
-    """RapidAPI client for CE flavor."""
+    """RapidAPI client for CE flavor.
+
+    Parameters
+    ----------
+    api_key : str
+        RapidAPI API key.
+    **kwargs : dict
+        Additional keyword arguments for the base Client.
+    """
 
     DEFAULT_ENDPOINT: ClassVar[str] = "https://judge0-ce.p.rapidapi.com"
     DEFAULT_HOST: ClassVar[str] = "judge0-ce.p.rapidapi.com"
@@ -578,7 +626,15 @@ def __init__(self, api_key, **kwargs):
 
 
 class RapidJudge0ExtraCE(Rapid):
-    """RapidAPI client for Extra CE flavor."""
+    """RapidAPI client for Extra CE flavor.
+
+    Parameters
+    ----------
+    api_key : str
+        RapidAPI API key.
+    **kwargs : dict
+        Additional keyword arguments for the base Client.
+    """
 
     DEFAULT_ENDPOINT: ClassVar[str] = "https://judge0-extra-ce.p.rapidapi.com"
     DEFAULT_HOST: ClassVar[str] = "judge0-extra-ce.p.rapidapi.com"
@@ -602,6 +658,8 @@ class Sulu(Client):
         Default request endpoint.
     api_key : str, optional
         Sulu API key.
+    **kwargs : dict
+        Additional keyword arguments for the base Client.
     """
 
     API_KEY_ENV: ClassVar[str] = "JUDGE0_SULU_API_KEY"
@@ -622,6 +680,8 @@ class SuluJudge0CE(Sulu):
     ----------
     api_key : str, optional
         Sulu API key.
+    **kwargs : dict
+        Additional keyword arguments for the base Client.
     """
 
     DEFAULT_ENDPOINT: ClassVar[str] = "https://judge0-ce.p.sulu.sh"
@@ -642,6 +702,8 @@ class SuluJudge0ExtraCE(Sulu):
     ----------
     api_key : str
         Sulu API key.
+    **kwargs : dict
+        Additional keyword arguments for the base Client.
     """
 
     DEFAULT_ENDPOINT: ClassVar[str] = "https://judge0-extra-ce.p.sulu.sh"