Index: kernel/generic/src/udebug/udebug.c
===================================================================
--- kernel/generic/src/udebug/udebug.c	(revision 0dd0f71fa885d92f7ddf540df7102fce0dca50b5)
+++ kernel/generic/src/udebug/udebug.c	(revision 3926f304505def449c2e06ef0f850cfc9d3ca437)
@@ -530,5 +530,6 @@
 				LOG("answer GO call with EVENT_FINISHED\n");
 				IPC_SET_RETVAL(t->udebug.go_call->data, 0);
-				IPC_SET_ARG1(t->udebug.go_call->data, UDEBUG_EVENT_FINISHED);
+				IPC_SET_ARG1(t->udebug.go_call->data,
+				    UDEBUG_EVENT_FINISHED);
 
 				ipc_answer(&ta->answerbox, t->udebug.go_call);
Index: kernel/generic/src/udebug/udebug_ipc.c
===================================================================
--- kernel/generic/src/udebug/udebug_ipc.c	(revision 0dd0f71fa885d92f7ddf540df7102fce0dca50b5)
+++ kernel/generic/src/udebug/udebug_ipc.c	(revision 3926f304505def449c2e06ef0f850cfc9d3ca437)
@@ -60,4 +60,11 @@
 }
 
+/** Process a BEGIN call.
+ *
+ * Initiates a debugging session for the current task. The reply
+ * to this call may or may not be sent before this function returns.
+ *
+ * @param call	The call structure.
+ */
 static void udebug_receive_begin(call_t *call)
 {
@@ -71,4 +78,8 @@
 	}
 
+	/*
+	 * If the initialization of the debugging session has finished,
+	 * send a reply.
+	 */
 	if (rc != 0) {
 		IPC_SET_RETVAL(call->data, 0);
@@ -77,4 +88,9 @@
 }
 
+/** Process an END call.
+ *
+ * Terminates the debugging session for the current task.
+ * @param call	The call structure.
+ */
 static void udebug_receive_end(call_t *call)
 {
@@ -87,4 +103,9 @@
 }
 
+/** Process a SET_EVMASK call.
+ *
+ * Sets an event mask for the current debugging session.
+ * @param call	The call structure.
+ */
 static void udebug_receive_set_evmask(call_t *call)
 {
@@ -100,4 +121,9 @@
 
 
+/** Process a GO call.
+ *
+ * Resumes execution of the specified thread.
+ * @param call	The call structure.
+ */
 static void udebug_receive_go(call_t *call)
 {
@@ -115,4 +141,9 @@
 }
 
+/** Process a STOP call.
+ *
+ * Suspends execution of the specified thread.
+ * @param call	The call structure.
+ */
 static void udebug_receive_stop(call_t *call)
 {
@@ -127,4 +158,9 @@
 }
 
+/** Process a THREAD_READ call.
+ *
+ * Reads the list of hashes of the (userspace) threads in the current task.
+ * @param call	The call structure.
+ */
 static void udebug_receive_thread_read(call_t *call)
 {
@@ -177,4 +213,9 @@
 }
 
+/** Process an ARGS_READ call.
+ *
+ * Reads the argument of a current syscall event (SYSCALL_B or SYSCALL_E).
+ * @param call	The call structure.
+ */
 static void udebug_receive_args_read(call_t *call)
 {
@@ -210,4 +251,9 @@
 }
 
+/** Process an MEM_READ call.
+ *
+ * Reads memory of the current (debugged) task.
+ * @param call	The call structure.
+ */
 static void udebug_receive_mem_read(call_t *call)
 {
@@ -240,8 +286,8 @@
 }
 
-/**
- * Handle a debug call received on the kernel answerbox.
- *
- * This is called by the kbox servicing thread.
+/** Handle a debug call received on the kernel answerbox.
+ *
+ * This is called by the kbox servicing thread. Verifies that the sender
+ * is indeed the debugger and calls the appropriate processing function.
  */
 void udebug_call_receive(call_t *call)