diff --git a/pyjapc/_japc.py b/pyjapc/_japc.py
index ecdf38fd1ef2ccebb45229a9c4b7c3c88af9a31f..09499d4d946e7782182f8909aa8a8a3f877bca99 100644
--- a/pyjapc/_japc.py
+++ b/pyjapc/_japc.py
@@ -47,7 +47,7 @@ class PyJapc:
     def __init__(
         self,
         selector: pyjapc_types.Selector = "LHC.USER.ALL",
-        incaAcceleratorName: str = "auto",
+        incaAcceleratorName: typing.Optional[str] = "auto",
         noSet: bool = False,
         timeZone: typing.Optional[pyjapc_types.Timezone] = "utc",
         logLevel: typing.Optional[pyjapc_types.LogLevel] = None,
@@ -70,7 +70,8 @@ class PyJapc:
                 Injector Control Architecture (InCA) framework.
 
                 It can be any of ``AD``, ``CTF3``, ``ISOLDE``, ``LEIR``, ``LHC``, ``LINAC4``, ``NORTH``, ``PS``,
-                ``PSB``, ``SCT``, ``SPS`` or can be even an empty string (``""``).
+                ``PSB``, ``SCT``, ``SPS`` or can be even an empty string (``""``). The valid values come
+                from the ``cern.accsoft.commons.domain.CernAccelerator`` class.
 
                 You might need to call :meth:`rbacLogin()` to make full use of InCA.
 
@@ -597,15 +598,15 @@ class PyJapc:
                 Then the result lists will be in the same order as the
                 parameterName list.
 
-            noPyConversion: Set to ``True`` if you want to get the raw JAPC
+            noPyConversion (bool): Set to ``True`` if you want to get the raw JAPC
                 ``ParameterValue`` object instead of a Python native type. You will
                 have to extract the values yourself.
 
-            unixtime: If ``True`` and ``noPyConversion`` is ``False``, the
+            unixtime (bool): If ``True`` and ``noPyConversion`` is ``False``, the
                 header will be converted but the ``acqStamp`` and ``cycleStamp`` will be
                 returned as seconds since epoch.
 
-            onValueReceived:
+            onValueReceived (function):
                 If you get an asynchronous simple parameter value, the
                 callback function should be like::
 
@@ -713,6 +714,7 @@ class PyJapc:
     def setParam(
         self,
         parameterName: str,
+        # TODO: There are more types needed here.
         parameterValue: typing.Union[bool, int, float, str, np.ndarray],
         checkDims: bool = True,
         dtype: typing.Optional[typing.Union[str, typing.Type]] = None,
@@ -1743,7 +1745,7 @@ class PyJapc:
         return val
 
     @typing.overload
-    def _convertValToPy(self, val: cern.japc.value.MapParameterValue) -> typing.Dict: ...
+    def _convertValToPy(self, val: cern.japc.value.MapParameterValue) -> typing.Dict[str, typing.Any]: ...
 
     @typing.overload
     def _convertValToPy(self, val: cern.japc.value.ParameterValue) -> typing.Any: