diff --git a/pcapkit/protocols/data/internet/hopopt.py b/pcapkit/protocols/data/internet/hopopt.py
index 8d49872038..e984f2beb4 100644
--- a/pcapkit/protocols/data/internet/hopopt.py
+++ b/pcapkit/protocols/data/internet/hopopt.py
@@ -210,11 +210,19 @@ def __init__(self, type: 'Enum_Option', action: 'int', change: 'bool', length: '
 
 
 class QuickStartOption(Option):
-    """Data model for HOPOPT Quick Start option."""
+    """Data model for HOPOPT Quick Start option.
+
+    .. versionchanged:: 1.5.0
+
+       ``rate`` is an :obj:`int` rather than a :obj:`float` (:issue:`2167`).
+
+    """
 
     #: QS function.
     func: 'QSFunction'
-    #: Rate request/report.
+    #: Rate request/report, in kbps: ``40 * 2 ** N`` for the Rate Request or
+    #: Rate Report field ``N``, or ``0`` if ``N`` is ``0`` (:rfc:`4782`
+    #: Section 3.1).
     rate: 'int'
 
 
diff --git a/pcapkit/protocols/data/internet/ipv4.py b/pcapkit/protocols/data/internet/ipv4.py
index 81ccf4abbb..f87ed2420d 100644
--- a/pcapkit/protocols/data/internet/ipv4.py
+++ b/pcapkit/protocols/data/internet/ipv4.py
@@ -409,11 +409,19 @@ def __init__(self, code: 'OptionNumber', length: 'int', type: 'OptionType', aler
 
 
 class QSOption(Option):
-    """Data model for IPv4 Quick Start (``QS``) option."""
+    """Data model for IPv4 Quick Start (``QS``) option.
+
+    .. versionchanged:: 1.5.0
+
+       ``rate`` is an :obj:`int` rather than a :obj:`float` (:issue:`2167`).
+
+    """
 
     #: QS function.
     func: 'QSFunction'
-    #: Rate request/report.
+    #: Rate request/report, in kbps: ``40 * 2 ** N`` for the Rate Request or
+    #: Rate Report field ``N``, or ``0`` if ``N`` is ``0`` (:rfc:`4782`
+    #: Section 3.1).
     rate: 'int'
 
 
diff --git a/pcapkit/protocols/data/internet/ipv6_opts.py b/pcapkit/protocols/data/internet/ipv6_opts.py
index 1b4d134245..2d8f763f55 100644
--- a/pcapkit/protocols/data/internet/ipv6_opts.py
+++ b/pcapkit/protocols/data/internet/ipv6_opts.py
@@ -219,11 +219,19 @@ def __init__(self, type: 'Enum_Option', action: 'int', change: 'bool', length: '
 
 
 class QuickStartOption(Option):
-    """Data model for IPv6-Opts Quick Start option."""
+    """Data model for IPv6-Opts Quick Start option.
+
+    .. versionchanged:: 1.5.0
+
+       ``rate`` is an :obj:`int` rather than a :obj:`float` (:issue:`2167`).
+
+    """
 
     #: QS function.
     func: 'QSFunction'
-    #: Rate request/report.
+    #: Rate request/report, in kbps: ``40 * 2 ** N`` for the Rate Request or
+    #: Rate Report field ``N``, or ``0`` if ``N`` is ``0`` (:rfc:`4782`
+    #: Section 3.1).
     rate: 'int'
 
 
diff --git a/pcapkit/protocols/data/transport/tcp.py b/pcapkit/protocols/data/transport/tcp.py
index 7b0d5eeb43..5baf4266a2 100644
--- a/pcapkit/protocols/data/transport/tcp.py
+++ b/pcapkit/protocols/data/transport/tcp.py
@@ -341,9 +341,17 @@ def __init__(self, kind: 'OptionNumber', length: 'int', digest: 'bytes') -> 'Non
 
 @info_final
 class QuickStartResponse(Option):
-    """Data model for TCP quick start response option."""
+    """Data model for TCP quick start response option.
 
-    #: Rate request.
+    .. versionchanged:: 1.5.0
+
+       ``req_rate`` is an :obj:`int` rather than a :obj:`float`
+       (:issue:`2167`).
+
+    """
+
+    #: Rate request, in kbps: ``40 * 2 ** N`` for the Rate Request field
+    #: ``N``, or ``0`` if ``N`` is ``0`` (:rfc:`4782` Section 3.1).
     req_rate: 'int'
     #: TTL difference.
     ttl_diff: 'int'
diff --git a/pcapkit/protocols/transport/tcp.py b/pcapkit/protocols/transport/tcp.py
index ef51e8125d..856010acea 100644
--- a/pcapkit/protocols/transport/tcp.py
+++ b/pcapkit/protocols/transport/tcp.py
@@ -2156,6 +2156,14 @@ def _make_tcp_options(self, options: 'list[Schema_Option | tuple[Enum_Option, di
         Returns:
             Tuple of options and total length of options.
 
+        Raises:
+            ProtocolError: If an option maker rejects its option, e.g. a user
+                timeout too large for 15 bits of minutes, or an MPTCP option
+                whose fields, or the segment's flags, it cannot encode.
+            ProtocolNotImplemented: If an option argument given by name, an
+                MPTCP ``subtype`` or an alternate checksum ``algorithm``, is
+                not in its namespace and has no default.
+
         Note:
             The options are emitted in the given order, ``NOP`` and ``EOOL``
             included, so that a parsed option list re-emits the same octets.
@@ -2975,6 +2983,10 @@ def _make_mptcp_join(self, subtype: 'Enum_MPTCPOption', opt: 'Optional[Data_MPTC
         Returns:
             Constructed option schema.
 
+        Raises:
+            ProtocolError: If the segment's flags are none of SYN, SYN/ACK and
+                ACK.
+
         """
         if Enum_Flags.SYN in self._flags and Enum_Flags.ACK not in self._flags:  # MP_JOIN-SYN
             return self._make_join_syn(subtype, opt, **kwargs)  # type: ignore[arg-type]