diff --git a/dev/test.sh b/dev/test.sh
index 8f8d9dedf6d..b8eeed14bc4 100755
--- a/dev/test.sh
+++ b/dev/test.sh
@@ -26,6 +26,10 @@ echo "- docformatter: start"
 python -m docformatter -c -r src/py/flwr e2e -e src/py/flwr/proto
 echo "- docformatter:  done"
 
+echo "- docsig: start"
+docsig src/py/flwr
+echo "- docsig:  done"
+
 echo "- ruff: start"
 python -m ruff check src/py/flwr
 echo "- ruff: done"
diff --git a/pyproject.toml b/pyproject.toml
index 11da893bec7..aa356835d98 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -134,6 +134,7 @@ pre-commit = "==3.5.0"
 sphinx-substitution-extensions = "2022.02.16"
 sphinxext-opengraph = "==0.9.1"
 docstrfmt = { git = "https://github.com/charlesbvll/docstrfmt.git", branch = "patch-1" }
+docsig = "==0.64.0"
 
 [tool.docstrfmt]
 extend_exclude = [
@@ -224,3 +225,7 @@ convention = "numpy"
 
 [tool.ruff.per-file-ignores]
 "src/py/flwr/server/strategy/*.py" = ["E501"]
+
+[tool.docsig]
+ignore-no-params = true
+exclude = 'src/py/flwr/proto/.*|src/py/flwr/.*_test\.py|src/py/flwr/cli/new/templates/.*\.tpl'
diff --git a/src/py/flwr/cli/config_utils.py b/src/py/flwr/cli/config_utils.py
index 79e4973ccf9..73ce779c3b5 100644
--- a/src/py/flwr/cli/config_utils.py
+++ b/src/py/flwr/cli/config_utils.py
@@ -90,6 +90,16 @@ def load_and_validate(
 ) -> tuple[Optional[dict[str, Any]], list[str], list[str]]:
     """Load and validate pyproject.toml as dict.
 
+    Parameters
+    ----------
+    path : Optional[Path] (default: None)
+        The path of the Flower App config file to load. By default it
+        will try to use `pyproject.toml` inside the current directory.
+    check_module: bool (default: True)
+        Whether the validity of the Python module should be checked.
+        This requires the project to be installed in the currently
+        running environment. True by default.
+
     Returns
     -------
     Tuple[Optional[config], List[str], List[str]]
diff --git a/src/py/flwr/client/app.py b/src/py/flwr/client/app.py
index 90c50aba7fa..54ed33aa66b 100644
--- a/src/py/flwr/client/app.py
+++ b/src/py/flwr/client/app.py
@@ -132,6 +132,11 @@ class `flwr.client.Client` (default: None)
         - 'grpc-bidi': gRPC, bidirectional streaming
         - 'grpc-rere': gRPC, request-response (experimental)
         - 'rest': HTTP (experimental)
+    authentication_keys : Optional[Tuple[PrivateKey, PublicKey]] (default: None)
+        Tuple containing the elliptic curve private key and public key for
+        authentication from the cryptography library.
+        Source: https://cryptography.io/en/latest/hazmat/primitives/asymmetric/ec/
+        Used to establish an authenticated connection with the server.
     max_retries: Optional[int] (default: None)
         The maximum number of times the client will try to connect to the
         server before giving up in case of a connection error. If set to None,
@@ -249,6 +254,11 @@ class `flwr.client.Client` (default: None)
         - 'grpc-bidi': gRPC, bidirectional streaming
         - 'grpc-rere': gRPC, request-response (experimental)
         - 'rest': HTTP (experimental)
+    authentication_keys : Optional[Tuple[PrivateKey, PublicKey]] (default: None)
+        Tuple containing the elliptic curve private key and public key for
+        authentication from the cryptography library.
+        Source: https://cryptography.io/en/latest/hazmat/primitives/asymmetric/ec/
+        Used to establish an authenticated connection with the server.
     max_retries: Optional[int] (default: None)
         The maximum number of times the client will try to connect to the
         server before giving up in case of a connection error. If set to None,
diff --git a/src/py/flwr/client/grpc_rere_client/connection.py b/src/py/flwr/client/grpc_rere_client/connection.py
index b4fa2837360..06701376fac 100644
--- a/src/py/flwr/client/grpc_rere_client/connection.py
+++ b/src/py/flwr/client/grpc_rere_client/connection.py
@@ -120,6 +120,9 @@ def grpc_request_response(  # pylint: disable=R0913, R0914, R0915
         authentication from the cryptography library.
         Source: https://cryptography.io/en/latest/hazmat/primitives/asymmetric/ec/
         Used to establish an authenticated connection with the server.
+    adapter_cls: Optional[Union[type[FleetStub], type[GrpcAdapter]]] (default: None)
+        A GrpcStub Class that can be used to send messages. By default the FleetStub
+        will be used.
 
     Returns
     -------
diff --git a/src/py/flwr/common/message.py b/src/py/flwr/common/message.py
index ce4fdb3dd82..4e792e8e02a 100644
--- a/src/py/flwr/common/message.py
+++ b/src/py/flwr/common/message.py
@@ -290,6 +290,11 @@ def create_error_reply(self, error: Error, ttl: float | None = None) -> Message:
             follows the equation:
 
             ttl = msg.meta.ttl - (reply.meta.created_at - msg.meta.created_at)
+
+        Returns
+        -------
+        message : Message
+            A Message containing only the relevant error and metadata.
         """
         # If no TTL passed, use default for message creation (will update after
         # message creation)
diff --git a/src/py/flwr/common/recordset_compat.py b/src/py/flwr/common/recordset_compat.py
index 35024fcd67d..4641b8f29c9 100644
--- a/src/py/flwr/common/recordset_compat.py
+++ b/src/py/flwr/common/recordset_compat.py
@@ -59,6 +59,11 @@ def parametersrecord_to_parameters(
     keep_input : bool
         A boolean indicating whether entries in the record should be deleted from the
         input dictionary immediately after adding them to the record.
+
+    Returns
+    -------
+    parameters : Parameters
+        The parameters in the legacy format Parameters.
     """
     parameters = Parameters(tensors=[], tensor_type="")
 
@@ -94,6 +99,11 @@ def parameters_to_parametersrecord(
         A boolean indicating whether parameters should be deleted from the input
         Parameters object (i.e. a list of serialized NumPy arrays) immediately after
         adding them to the record.
+
+    Returns
+    -------
+    ParametersRecord
+        The ParametersRecord containing the provided parameters.
     """
     tensor_type = parameters.tensor_type
 
diff --git a/src/py/flwr/common/retry_invoker.py b/src/py/flwr/common/retry_invoker.py
index 303d5596f23..9785b0fbd9b 100644
--- a/src/py/flwr/common/retry_invoker.py
+++ b/src/py/flwr/common/retry_invoker.py
@@ -38,6 +38,11 @@ def exponential(
         Factor by which the delay is multiplied after each retry.
     max_delay: Optional[float] (default: None)
         The maximum delay duration between two consecutive retries.
+
+    Returns
+    -------
+    Generator[float, None, None]
+        A generator for the delay between 2 retries.
     """
     delay = base_delay if max_delay is None else min(base_delay, max_delay)
     while True:
@@ -56,6 +61,11 @@ def constant(
     ----------
     interval: Union[float, Iterable[float]] (default: 1)
         A constant value to yield or an iterable of such values.
+
+    Returns
+    -------
+    Generator[float, None, None]
+        A generator for the delay between 2 retries.
     """
     if not isinstance(interval, Iterable):
         interval = itertools.repeat(interval)
@@ -73,6 +83,11 @@ def full_jitter(max_value: float) -> float:
     ----------
     max_value : float
         The upper limit for the randomized value.
+
+    Returns
+    -------
+    float
+        A random float that is less than max_value.
     """
     return random.uniform(0, max_value)
 
diff --git a/src/py/flwr/server/client_manager.py b/src/py/flwr/server/client_manager.py
index 175bd4a786e..9949e29f8f7 100644
--- a/src/py/flwr/server/client_manager.py
+++ b/src/py/flwr/server/client_manager.py
@@ -47,6 +47,7 @@ def register(self, client: ClientProxy) -> bool:
         Parameters
         ----------
         client : flwr.server.client_proxy.ClientProxy
+            The ClientProxy of the Client to register.
 
         Returns
         -------
@@ -64,6 +65,7 @@ def unregister(self, client: ClientProxy) -> None:
         Parameters
         ----------
         client : flwr.server.client_proxy.ClientProxy
+            The ClientProxy of the Client to unregister.
         """
 
     @abstractmethod
diff --git a/src/py/flwr/server/superlink/fleet/grpc_bidi/grpc_server.py b/src/py/flwr/server/superlink/fleet/grpc_bidi/grpc_server.py
index b161492000f..70283c0e129 100644
--- a/src/py/flwr/server/superlink/fleet/grpc_bidi/grpc_server.py
+++ b/src/py/flwr/server/superlink/fleet/grpc_bidi/grpc_server.py
@@ -174,7 +174,7 @@ def generic_create_grpc_server(  # pylint: disable=too-many-arguments
 
     Parameters
     ----------
-    servicer_and_add_fn : Tuple
+    servicer_and_add_fn : tuple
         A tuple holding a servicer implementation and a matching
         add_Servicer_to_server function.
     server_address : str
@@ -214,6 +214,8 @@ def generic_create_grpc_server(  # pylint: disable=too-many-arguments
             * CA certificate.
             * server certificate.
             * server private key.
+    interceptors : Optional[Sequence[grpc.ServerInterceptor]] (default: None)
+        A list of gRPC interceptors.
 
     Returns
     -------
diff --git a/src/py/flwr/server/superlink/state/sqlite_state.py b/src/py/flwr/server/superlink/state/sqlite_state.py
index 73c121b01b4..182b55d6f77 100644
--- a/src/py/flwr/server/superlink/state/sqlite_state.py
+++ b/src/py/flwr/server/superlink/state/sqlite_state.py
@@ -151,6 +151,11 @@ def initialize(self, log_queries: bool = False) -> list[tuple[str]]:
         ----------
         log_queries : bool
             Log each query which is executed.
+
+        Returns
+        -------
+        list[tuple[str]]
+            The list of all tables in the DB.
         """
         self.conn = sqlite3.connect(self.database_path)
         self.conn.execute("PRAGMA foreign_keys = ON;")
diff --git a/src/py/flwr/server/superlink/state/utils.py b/src/py/flwr/server/superlink/state/utils.py
index 00ba02d2e43..db44719c6a8 100644
--- a/src/py/flwr/server/superlink/state/utils.py
+++ b/src/py/flwr/server/superlink/state/utils.py
@@ -100,11 +100,6 @@ def convert_uint64_values_in_dict_to_sint64(
         A dictionary where the values are integers to be converted.
     keys : list[str]
         A list of keys in the dictionary whose values need to be converted.
-
-    Returns
-    -------
-    None
-        This function does not return a value. It modifies `data_dict` in place.
     """
     for key in keys:
         if key in data_dict:
@@ -122,11 +117,6 @@ def convert_sint64_values_in_dict_to_uint64(
         A dictionary where the values are integers to be converted.
     keys : list[str]
         A list of keys in the dictionary whose values need to be converted.
-
-    Returns
-    -------
-    None
-        This function does not return a value. It modifies `data_dict` in place.
     """
     for key in keys:
         if key in data_dict: