diff --git a/src/sgame/sg_bot_util.cpp b/src/sgame/sg_bot_util.cpp
index 56982ea90bd..d3a4c3931a1 100644
--- a/src/sgame/sg_bot_util.cpp
+++ b/src/sgame/sg_bot_util.cpp
@@ -1576,6 +1576,19 @@ void BotAimAtEnemy( gentity_t *self )
 	}
 }
 
+// the argument 'target' is somehow related to the bot's frame of reference.
+// that is, it only works with the usual absolute coordinates if the bot's
+// current normal vector (x, y, z) is (0, 0, 1), as given by:
+//   vec3_t normalVector;
+//   BG_GetClientNormal( &self->client->ps, normalVector);
+// this is not the case if an alien bot activates the wall climb, and is on
+// a non-horizontal surface.
+// TODO:
+// maybe make two functions instead of this one:
+//   - BotAimAtLocationRelative  (this function)
+//   - BotAimAtLocationAbsolute  (for locations in the global frame of reference)
+// alternatively, provide a linear map and its inverse, to transform between
+// the two frames of reference.
 void BotAimAtLocation( gentity_t *self, const glm::vec3 &target )
 {
 	glm::vec3 aimVec, aimAngles, viewBase;