Somewhere to start
An empty world, and Cog.
Nothing built yet. Just a place, and a builder standing in it waiting to be asked.
Play Minecraft with an AI
Ask for anything.
Then play it with them.
Cubelings is a Minecraft server with an AI player already standing in it. Tell Cog what you want and they go and build it while you watch the blocks go down: a canyon with a waterfall, a walk-in house shaped like SpongeBob. There is no schematic file to import and nothing for anyone to install.
Ask for a game instead and they write you one. Rules, a scoreboard, the lot. It is running in the world you are standing in before you have put your pickaxe away.
- One sentence is the whole interface. Say what you want and watch it go up, block by block, while you stand there.
- Games you can play invented on the spot. Ask for one and you are playing it minutes later, in the world you were already in.
- A second player who mines with you, follows you down a hole, and answers in the chat like anybody else would.
- Only who you invite gets in. The world is whitelisted and on no public server list, and your friends pay nothing.
Cog
Cog
Ask for something
"Build me a road to the village."
And they go and do it. Not a loading bar — you stand there and watch the blocks go down, one after another, until there is a road where there was grass.
Ask for more
Houses. A well. A field.
Windows that light up when it gets dark. Water running down the middle of the wheat. Lamps along the road because they thought you would want them.
Ask for something silly
A ferris wheel that actually turns.
Not a decoration. There is a lever at the bottom. Flip it and the whole thing goes round, and the seats stay level all the way over the top.
And they tell you the truth
Cog checks their own work.
When Cog finishes something they go back over it and count. If a wall has a hole in it, they say so. You will never find out three days later that half a bridge is missing.
Road's done — runs the whole way, no gaps.
Wheel turns. Seats stay level over the top.
The lever works. Go and pull it.One take, no cuts
Six things, from six sentences.
Every build in this film started as one line typed into the chat, and you will see that line as you fly over it. Stay for the treehouse — it goes up from nothing while you watch.
Made on request
Fifteen things a Minecraft AI built, from fifteen sentences.
Nothing here came out of a catalogue. Each one started as a single line typed into the chat, and each one is standing in a world right now — not in a schematic file waiting to be imported. Take hold of any of them and turn it round.
A stone dragon on an outcrop
"Wings folded, head up, mouth open."
30,719 blocks
A giant cat, standing
"Big enough to walk under."
21,845 blocks
A pirate galleon, out at sea
"Cannons run out, flag up top."
30,263 blocks
A steam locomotive on a timber trestle
"On a bridge, like it is crossing a valley."
17,044 blocks
A treehouse village up a giant oak
"Rope bridges between the huts."
35,252 blocks · you can go inside
A windmill with sails that turn
"And I want the sails to actually go round."
24,638 blocks
A frog mansion you can walk inside
"With rooms and floors inside it."
23,311 blocks · you can go inside
A volcano with lava running down it
"Make it look like it just went off."
21,803 blocks
A house shaped like SpongeBob
"And I want to go inside it."
24,688 blocks · you can go inside
A wizard’s tower with a spiral stair
"Put a library in it and a stair all the way up."
14,212 blocks
A giant electric guitar on the grass
"Absolutely enormous, lying on the ground."
16,653 blocks
A pagoda with a koi pond
"With a red bridge over the water."
23,498 blocks
A space station with a docking ring
"Floating, with a ring around it."
9,834 blocks
A glass dome on the sea floor
"An underwater base I can walk out to."
15,234 blocks
A chess set part way through a game
"Big enough to walk between the pieces."
10,602 blocks
Getting started
Three steps to a world of your own.
- 1
Pick a plan
Your world is up a few minutes later, with Cog already standing in it. Nothing to install, no server to configure, no router to argue with.
- 2
Tell Cog what you want
In the chat box, in your own words. "Build a lighthouse on that headland." "Make us a soccer game." Cog asks if something is unclear, and then gets on with it.
- 3
Send your mates the address
They open the copy of Minecraft they already own and join. No mod and no launcher. However many of them there are, they play free.
Make it yours
Cog is only the name it turns up with.
It arrives called Cog because something has to be called something. Rename it, put any Minecraft skin on it, and set how you want it to behave.
Give it a name
Bramble. Pickle. Your dog. Whatever your world decides. That is the name it answers to in the chat and the name on everything it builds.
Give it a face
Drop in any Minecraft skin and that is who turns up. Same as skinning your own character — no file wrangling, no launcher, and everybody in the world sees it.
Give it a manner
Chatty or quiet. Cheeky or straight down the line. Ask before big builds, or just get on with it. It is a setting, not a personality you have to put up with.
Every world gets its own. Two Cubelings worlds have never had to have the same one.
Who it is for
Four people usually turn up on the same day.
The one with the ideas
Who wants a pirate galleon, a working rollercoaster and a canyon with a waterfall down it, and is not going to spend a fortnight placing blocks one at a time to find out whether it was worth building.
The group of mates
Who want one world that is always up, that nobody has to host on their own machine and pay for alone, and that has something new in it every time they log on.
Whoever ends up running it
Who is tired of being the server admin — the version arguments, the plugin that broke, the nine o'clock message saying it is down. Nothing here needs administering.
The parent paying for it
Who wants a safe Minecraft server for their kid and not a public one. This world is whitelisted: you add their friends by name, no stranger can find it, and Cog refuses anything it should not build however it is asked. What Cog will and will not do →
For purists
"An AI building it for you ruins Minecraft."
Some players mean that, and for them it is true. If placing the blocks is the part you came for, a builder has nothing to give you — buy the hosting on its own and never speak to Cog. In survival Cog cannot shortcut anything anyway: they walk there, mine it, craft it and take the hits, the same as you.
And the nine-year-old asking for a dragon castle was never going to spend a fortnight on WorldEdit to get one. Nothing was taken off them. They described it, and then they got to watch it go up.
Pricing
Start free. Then $12 a month for the world, however many of you are in it.
One person pays for the world. Everybody they invite joins free, with the game they already own. Cancel whenever you like, and take the whole world with you if you go.
- Free Try it up to 3 players · 5 big builds to use up
- $12 Starter up to 5 players · 20 big builds a month
- $24 Crew up to 15 players · 60 big builds a month
- $48 Club up to 50 players · 200 big builds a month
What you can ask for
Nine things they will do without being told twice.
Not a menu of settings. You say it the way you would say it to a friend, and they go and do it while you watch.
Your world
It is still there when you get back.
A Cubelings world does not pause when you log off. It keeps running on an ordinary Minecraft server underneath, so it is exactly where you left it — mid-build, mid-farm — the next time anyone signs in.
Cog lives on the server itself, joining your world as a player, never on a player's machine. Nobody needs to install anything to see them work.
- It is yours aloneYour world is your world. The only builds in it are the ones you and your friends asked for.
- Nothing to installYour friends open the copy of Minecraft they already own and join. They need no mod and they pay nothing.
- Nothing is ever lostThe world is backed up on a schedule, so an afternoon's building is never one accident away from gone.
- Only who you inviteAdd your friends by name and that is who can get in. Nobody wanders in, and it is on no public list.
No waiting around
New things appear while you are standing there.
On most servers, adding anything new means everyone gets thrown out while it restarts. Not here. Five people are standing in a field; a pitch, two goals, floodlights and a lit scoreboard arrive around them; and they are the same five people, on the same spots, playing it a moment later. Nobody reconnected. Nobody installed anything. Nothing even flickered.
1,937ms from nothing to a working machine, live in the world — nobody kicked, nobody reconnecting, nobody installing anything
21s and when something needs to go deeper than that, from writing it to running it — including the one restart it does need
Creative 0 blocks · a town in seconds Survival 0 blocks · chopped, carried, laid one at a time
Two ways to play
Cog can conjure it, or they can go and earn it.
On the left, creative: a whole street goes up in the time it takes to say what you want. On the right, survival, on the same clock — Cog walks to a tree, swings an axe at it until it comes down, carries the wood back, and lays it. The cottage is still four courses short when the town is finished. Nothing on that side is sped up. The gap is the point.
Creative
Places blocks directly — no gathering, no crafting, no travel time. This is the mode for a village, a road across the map, a ferris wheel that has to actually turn: builds where the point is the finished structure.
Survival
Cog gathers, crafts and mines under the same rules you do, and can come back with less than they hoped for. Cog fights when something attacks, retreats when they are hurt, and leaves ore alone when their pickaxe would only destroy it.
Building
Roads that bend round the hill instead of over it.
A road is not a straight line dropped between two points. The route reads the ground it crosses: it widens at corners so the shoulder does not read as a trench, and bridges water instead of stopping dead at the bank.
Structures are placed to the block, from a description in plain English — no schematic file to prepare, no in-game commands to type.
"cobblestone road from the well to the farm, three wide"
- route bridges the stream, no dead ends
- width 3, shoulders graded at corners
- fence one cell outside the road, never doubled
- lighting placed as it goes
Things that move
Doors that open. Wheels that turn. Traps that fire.
Ask for a secret door and you get a real one: sticky pistons, wire and a lever, laid block by block the way you would lay it yourself. Flip the lever and a solid wall slides across the doorway. Flip it back and the doorway is simply there again. It works the first time, and the hundredth.
Getting redstone right is the part that beats everyone. Wiring is fiddly and one wrong block kills the whole circuit — hard enough that when somebody sat the best AI models going down in front of it, they got it right about a quarter of the time.
So Cog does not work the wiring out on the spot. Cog builds from circuits that have already been made and tested — which is why their lever does what a lever should. How Cog checks their own work →
Click the pitch to take a shot
New rules, while you are standing in it
Ask for a game and you get a playable one.
Ask for soccer and you do not get a field and a shrug. Cog lays the pitch — markings, centre circle, goal frames in red and blue glass, a pad at each end — and then writes the rules that make it a game. Stand on your team's pad and it hands you snowballs and a bit of speed. Put one through the goal mouth and the score goes up, the whistle goes, and everyone gets told. First to five and the fireworks go off.
Then it goes into the running server. Nobody is kicked, nothing restarts, no plugin gets installed, and your friends carry on playing the ordinary game they already own. The server simply did not know how to play soccer a second and a half ago, and now it does.
1,641ms
from "make us a soccer game" to nine rules live on the
server — and every one of those nine was then triggered on
purpose to check it fires. Across six games, all
67 of 67 rules fired.
Why you can trust them near your world
Cog owns up when they get it wrong.
Anyone can show you a photo of a finished build. When Cog finishes one they walk back over it and count what is actually there — and then tell you, in the chat, in words. Not "done". The numbers they found.
CogRoad's finished. 357 columns, all one connected piece, no holes in it, and nothing along it you can't walk straight up.
CogWheel's up. All 92 parts, and every seat is exactly twelve blocks out from the middle — I measured them rather than trusting the drawing.
CogHouse is done, and you can get inside it — I know because I walked in: sixteen blocks past the wall, standing in the middle of him.
That is the whole difference. You will never find out on Saturday that the bridge you crossed on Tuesday had a gap in the middle of it.
Cog
Actual transcript, unedited
go mine me some iron
I'm heading down to mine some iron! Should be back up in a couple minutes with the ore.
what are you up to?
I was just about to head underground to mine iron! Want me to grab anything else while I'm down there?
Done! I mined 1 iron ore from Y:56 and made it back safely — found 4 total but only had room for 1.
The last line arrived on its own, two minutes later.
An AI player, in the world with you
Ask them what they are up to. Cog will tell you.
Cog joins the world as a player and behaves like one. Cog holds a real conversation, follows you if you ask, and has a personality rather than a script of canned lines.
Ask them for something that takes a while and they say so straight away, then come back and tell you when the job is actually done.
refused
Your world, your rules
A private Minecraft server, whitelisted to the people you name.
Your world is on no public server list, so nobody finds it and nobody wanders in. Cog refuses anything inappropriate, and the refusal does not change because a different player asks or the request is reworded. Cog will not wreck someone else's build, tells you what they did after every job, and anything they build can be undone in one command.
Early access
Be in the first worlds.
We are opening a small number of worlds to begin with. Put your name down and we will tell you when yours is ready. One email, when it is ready.
Questions
Straight answers.
What does it cost?
Plans start at $12 a month for one world with Cog in it, and everybody you invite joins free. You need your own copy of Minecraft Java Edition, the same as you always have. Cancel any time, and you can download your world and keep it.
Is it safe for kids, and safe to leave running?
Yes, and it is built that way on purpose. The world is whitelisted — you name the players who can join, and it is on no public server list for anybody else to find. Cog refuses anything inappropriate no matter who asks, they will not break other people’s builds, and everything they do is written down and can be undone.
Does Cog play with us, or only build?
Both. Cog joins your world as a player, so they can follow you, mine with you, fight what attacks you and answer in the chat while they do it. In survival they play by the rules you play by. Ask them for a game and they write one you can all play together.
Is using an AI in Minecraft cheating?
In creative, placing blocks straight down is what creative mode is for. In survival Cog plays by your rules — they walk there, mine the iron, craft at a table and take the damage, with nothing spawned in. And if you would rather have no AI at all, the same hosting is sold without Cog in it.
Can we make it ours?
That is rather the point. Cog is only the name and face it arrives with — rename it, drop in any Minecraft skin, and set how it behaves. Every world gets its own.
Do my friends need to install anything?
No. Nothing, no mods, no launcher. They open Minecraft the way they always do and join. Cog lives on the server, not on your computer.
Do I need to know anything technical?
No. There is no server to set up, no port forwarding, no config file. You pick a plan, your world appears, and you tell Cog what you want in the chat box, in ordinary words.
How long does Cog take?
A road or a house goes up in seconds while you stand there. Something they have to design from scratch — a dragon, a house shaped like a cartoon character — takes a few minutes of thinking first, and then goes up in seconds. Asking for a second copy of something they have already made takes about three seconds.
What if they build it wrong?
Cog tells you. Cog checks their own work on finishing and says what they found, including when it did not go to plan. And anything they build can be undone.
Does Cog cheat?
Only if you want them to. In creative they place things instantly, which is handy when you have asked for a castle. In survival they play by the same rules you do — they have to go and find the wood, and sometimes they come back with less than they hoped.
Which games can I use it with?
Minecraft Java Edition today. Hytale is next — it opened up in January 2026 and was built for exactly this kind of thing.