diff --git a/api/icsneoc/icsneoc.cpp b/api/icsneoc/icsneoc.cpp
index 0633005..63cdd0f 100644
--- a/api/icsneoc/icsneoc.cpp
+++ b/api/icsneoc/icsneoc.cpp
@@ -243,7 +243,8 @@ bool icsneo_setPollingMessageLimit(const neodevice_t* device, size_t newLimit) {
 	return true;
 }
 
-int icsneo_addMessageCallback(const neodevice_t* device, void (*callback)(neomessage_t)) {
+int icsneo_addMessageCallback(const neodevice_t* device, void (*callback)(neomessage_t), void* filter) {
+	(void)filter; // unused for now
 	if(!icsneo_isValidNeoDevice(device))
 		return -1;
 
diff --git a/docs/Usage.rst b/docs/Usage.rst
index 9a7dd00..e2df898 100644
--- a/docs/Usage.rst
+++ b/docs/Usage.rst
@@ -66,6 +66,7 @@ Message Callbacks and Polling
 In order to handle messages, users may register message callbacks, which are automatically called whenever a matching message is received.
 Message callbacks consist of a user-defined ``std::function< void( std::shared_ptr<Message> ) >`` and optional message filter used for matching.
 Registering a callback returns an ``int`` representing the id of the callback, which should be stored by the user and later used to remove the callback when desired.
+Note that this functionality is only available in C and C++.
 
 The default method of handling messages is to enable message polling, which is built upon message callbacks.
 Enabling message polling will register a callback that stores each received message in a buffer for later retrieval.
diff --git a/include/icsneo/icsneoc.h b/include/icsneo/icsneoc.h
index 946a6a9..82419a6 100644
--- a/include/icsneo/icsneoc.h
+++ b/include/icsneo/icsneoc.h
@@ -284,8 +284,21 @@ extern size_t DLLExport icsneo_getPollingMessageLimit(const neodevice_t* device)
  */
 extern bool DLLExport icsneo_setPollingMessageLimit(const neodevice_t* device, size_t newLimit);
 
-extern int DLLExport icsneo_addMessageCallback(const neodevice_t* device, void (*callback)(neomessage_t));
+/**
+ * \brief Adds a message callback to the specified device.
+ * \param[in] device A pointer to the neodevice_t structure specifying the device to operate on.
+ * \param[in] callback A function pointer with void return type and a single neomessage_t parameter
+ * \param[in] filter Unused for now. Exists as a placeholder here for future backwards-compatibility.
+ * \returns the id of the callback added, or -1 if the operation failed.
+ */
+extern int DLLExport icsneo_addMessageCallback(const neodevice_t* device, void (*callback)(neomessage_t), void* filter);
 
+/**
+ * \brief Removes a message callback from the specified device.
+ * \param[in] device A pointer to the neodevice_t structure specifying the device to operate on.
+ * \param[in] id The id of the callback to remove
+ * \returns True if the callback was successfully removed.
+ */
 extern bool DLLExport icsneo_removeMessageCallback(const neodevice_t* device, int id);
 
 /**
@@ -743,7 +756,7 @@ fn_icsneo_getPollingMessageLimit icsneo_getPollingMessageLimit;
 typedef bool(*fn_icsneo_setPollingMessageLimit)(const neodevice_t* device, size_t newLimit);
 fn_icsneo_setPollingMessageLimit icsneo_setPollingMessageLimit;
 
-typedef int(*fn_icsneo_addMessageCallback)(const neodevice_t* device, void (*callback)(neomessage_t));
+typedef int(*fn_icsneo_addMessageCallback)(const neodevice_t* device, void (*callback)(neomessage_t), void* filter);
 fn_icsneo_addMessageCallback icsneo_addMessageCallback;
 
 typedef bool(*fn_icsneo_removeMessageCallback)(const neodevice_t* device, int id);