diff --git a/mods/MAPGEN/mcl_geodes/init.lua b/mods/MAPGEN/mcl_geodes/init.lua
index 413a8fbba..d2debf7cd 100644
--- a/mods/MAPGEN/mcl_geodes/init.lua
+++ b/mods/MAPGEN/mcl_geodes/init.lua
@@ -8,7 +8,7 @@ local adjacents = {
 }
 
 local function makegeode(pos,pr)
-	local size = pr:next(4,12)
+	local size = pr:next(2,8)
 	local p1 = vector.offset(pos,-size,-size,-size)
 	local p2 = vector.offset(pos,size,size,size)
 	local nn = minetest.find_nodes_in_area(p1,p2,{"group:material_stone"})
diff --git a/mods/MAPGEN/mcl_structures/API.md b/mods/MAPGEN/mcl_structures/API.md
new file mode 100644
index 000000000..52d40b642
--- /dev/null
+++ b/mods/MAPGEN/mcl_structures/API.md
@@ -0,0 +1,27 @@
+# mcl_structures
+Structure placement API for MCL2.
+
+## mcl_structures.register_structure(name,structure definition)
+### structure definition
+{
+	fill_ratio = OR noise = {},
+	biomes = {},
+	y_min =,
+	y_max =,
+	place_on = {},
+	spawn_by = {},
+	num_spawn_by =
+	flags = (default: "place_center_x, place_center_z, force_placement")
+	(same as decoration def)
+	y_offset =, --can be a number or a function returning a number
+	filenames = {} OR place_func = function(pos,filename)
+	-- filenames can be a list of any schematics accepted by mcl_structures.place_schematic
+	after_place = function(pos)
+}
+## mcl_structures.registered_structures
+Table of the registered structure defintions indexed by name.
+
+## mcl_structures.place_structure(pos, def, pr)
+Places a structure using the mapgen placement function
+
+## mcl_structures.place_schematic(pos, schematic, rotation, replacements, force_placement, flags, after_placement_callback, pr, callback_param)
diff --git a/mods/MAPGEN/mcl_structures/api.lua b/mods/MAPGEN/mcl_structures/api.lua
index 5e0858fb1..be86df530 100644
--- a/mods/MAPGEN/mcl_structures/api.lua
+++ b/mods/MAPGEN/mcl_structures/api.lua
@@ -72,6 +72,7 @@ function mcl_structures.register_structure(name,def,nospawn) --nospawn means it
 		end)
 	end
 	minetest.register_node(":"..structblock, {drawtype="airlike", walkable = false, pointable = false,groups = sbgroups})
+	def.structblock = structblock
 	mcl_structures.registered_structures[name] = def
 end
 
diff --git a/mods/MAPGEN/mcl_structures/init.lua b/mods/MAPGEN/mcl_structures/init.lua
index 665fbf4c0..a82dffbff 100644
--- a/mods/MAPGEN/mcl_structures/init.lua
+++ b/mods/MAPGEN/mcl_structures/init.lua
@@ -630,9 +630,8 @@ minetest.register_on_mods_loaded(function()
 			else
 				for n,d in pairs(mcl_structures.registered_structures) do
 					if n == param then
-						mcl_structures.place_structure(pos,d,PseudoRandom(os.clock()))
-						minetest.chat_send_player(name, message)
-						return
+						mcl_structures.place_structure(pos,d,pr)
+						return true,message
 					end
 				end
 				message = S("Error: Unknown structure type. Please use “/spawnstruct <type>”.")
diff --git a/mods/MAPGEN/mcl_structures/mod.conf b/mods/MAPGEN/mcl_structures/mod.conf
index 3150c7cec..c19113ad4 100644
--- a/mods/MAPGEN/mcl_structures/mod.conf
+++ b/mods/MAPGEN/mcl_structures/mod.conf
@@ -1,4 +1,4 @@
 name = mcl_structures
-author = Wuzzy
-description = Structures for MCL2
+author = Wuzzy, cora
+description = Structure placement for MCL2
 depends = mcl_loot