diff --git a/src/hooks/dhcp/bootp/bootp.dox b/src/hooks/dhcp/bootp/bootp.dox
index 68489b027c..2af148b199 100644
--- a/src/hooks/dhcp/bootp/bootp.dox
+++ b/src/hooks/dhcp/bootp/bootp.dox
@@ -65,4 +65,10 @@ are removed from the response. When the packed response is shorter than
 the BOOTP minimum size (300 octets) it is padded after the END option
 by nuls up to this size.
 
+In case any other library sets the SKIP flag before pkt4_send, an exception
+with the message "the packet pack already handled" will be thrown, to
+indicate that the action can not be properly performed.
+To fix this, all other libraries which might set the SKIP flag must appear
+in the server configuration after this library.
+
 */
diff --git a/src/hooks/dhcp/flex_option/flex_option.dox b/src/hooks/dhcp/flex_option/flex_option.dox
index b85863204f..0f32bf8d02 100644
--- a/src/hooks/dhcp/flex_option/flex_option.dox
+++ b/src/hooks/dhcp/flex_option/flex_option.dox
@@ -112,6 +112,12 @@ applied by the template @c process located in flex_option.h. When
 required the expression is evaluated on the query packet and the result
 is used by the action for instance to add a new option.
 
+In case any other library sets the SKIP flag before pkt4_send or pkt6_send, an
+exception with the message "the packet pack already handled" will be thrown, to
+indicate that the action can not be properly performed.
+To fix this, all other libraries which might set the SKIP flag must appear in the
+server configuration after this library.
+
 @section libdhcp_flex_optionMTCompatibility Multi-Threading Compatibility
 
 The libdhcp_flex_option hooks library is compatible with multi-threading.
diff --git a/src/hooks/dhcp/user_chk/libdhcp_user_chk.dox b/src/hooks/dhcp/user_chk/libdhcp_user_chk.dox
index 84dc942901..9c7508a6d7 100644
--- a/src/hooks/dhcp/user_chk/libdhcp_user_chk.dox
+++ b/src/hooks/dhcp/user_chk/libdhcp_user_chk.dox
@@ -82,6 +82,12 @@ flow upon receipt of an inbound request is the same and is as follows:
     This final step is what produces the real time record, referred to as the
     "user check outcome" file.
 
+In case any other library sets the SKIP flag before pkt4_send or pkt6_send, an
+exception with the message "the packet pack already handled" will be thrown, to
+indicate that the action can not be properly performed.
+To fix this, all other libraries which might set the SKIP flag must appear in the
+server configuration after this library.
+
 ## Using the library
 Two steps are required in order to use the library:
 -# The user registry file must be created and deployed