add mobs:is_invisible() function, update api.txt

api.lua

@@ -19,7 +19,7 @@ end
 
 mobs = {
 	mod = "redo",
-	version = "20241114",
+	version = "20241116",
 	spawning_mobs = {},
 	translate = S,
 	node_snow = has(minetest.registered_aliases["mapgen_snow"])
@@ -1217,6 +1217,10 @@ local function is_invisible(self, player_name)
 	end
 end
 
+function mobs:is_invisible(self, player_name)
+	return is_invisible(self, player_name)
+end
+
 -- should mob follow what I'm holding ?
 
 function mob_class:follow_holding(clicker)

api.txt

@@ -904,3 +904,17 @@ Rideable Horse Example Mob
 --------------------------
 
 See mob_horse mod https://codeberg.org/tenplus1/mob_horse
+
+
+External Functions
+------------------
+
+These are a list of utility functions that can be called from 3rd party mods.
+
+mobs:alias_mob(old_name, new_name)
+mobs:is_invisible(self, player_name)
+mobs:is_dangerous(self, nodename)
+mobs:yaw_to_pos(self, target, rotation_steps)
+mobs:line_of_sight(self, pos1, pos2)
+mobs:set_animation(self, animation)
+mobs:yaw(self, yaw, rotation_steps)