No servers, no netcode, no code. Build with your AI agent, share a link, and play with friends in seconds.
Free for your first 1,000 players a month. No card required.
The whole loop, start to finish.
Move your square and every visitor here sees it, live. The second pane is another, separate client in the same room, and a phone or another tab can join it too.
Join from your phone. Scan it and your phone is one more player in this same room.Bring someone. Send them this link and they land in this same room. multiplayeragent.com/demo
Every visitor on this page joins one real room, named homepage, on the same realtime service and with the same one-script SDK your game would use. Your square is the one with the ring. Other people's squares appear while they move and fade after ten seconds standing still; the count still includes them.
Each client can only write its own player. The move carries no player id: the server fills it in from the connection, so no page, however it is edited, can move anyone else's square. That is the same rule your game gets.
The round trip in each pane is measured, not simulated: the time from your move to the room confirming it. When a room fills up, the next arrivals get another copy of it automatically, which is how a game on this service grows too.
<script src="https://api.multiplayeragent.com/sdk/mp.global.js"></script>
const mp = await MP.join({
key: "pk_live_5f3a91c2", // from your dashboard
room: "dots-arena", // any name; created on first join
});
mp.me.set({ x: 100, y: 50 }); // your own player
mp.onState((state) => {
draw(state.entities.players); // everybody, live
});You do not type this. It is what comes back: the key the agent made, the room it named, and the two calls your game uses. You can wire it up by hand if you would rather, but nothing about the loop asks you to.
yourgame.com/?room=dots-arenaAnyone with the link is in the room.
Neither of them asks you to write netcode, and neither of them asks you to write the client either.
Describe the game, watch it appear beside the chat, and play it from a link. Your whole team in one session, nothing to install.
Claude Code, Cursor, any MCP client. Twelve tools, the same rooms, and a client that already talks to them.
Multiplayer is the hard part, and it is rarely the only part. These are the pieces you would otherwise assemble from three vendors and a weekend, and every one of them is on every plan, the free tier included.
A room is just a name. The first player to use it creates it, and each client writes only its own player.
How to add multiplayerDeploy a small script and the room decides. Clients send inputs, and the answer is the only version of events that exists.
Read about server-side rulesAn identity on first load, a username whenever they want one, and the save underneath never changes.
What a player carriesEach game gets its own key and its own analytics. The plan is bought once and the players are pooled across everything you ship.
See what each plan includesAlso on every plan, the free tier included: leaderboards that clients submit to directly; player-made content, with publishing, voting and moderation already built; payments in one call, with nothing for you to configure and unlocks the client cannot fake (payouts to your own account are coming soon); and ads on your own publisher id, where you keep everything they earn.
One room type covers all of this. The plan changes how much of it you get, never which parts, so none of the list below is a tier you have to reach.
Contested physics is the one thing to think about: put the arbitration in server logic and the room decides, rather than two clients disagreeing. The comparison guide goes through how to choose, including when the answer is somebody else.
Made on the platform and published to the arcade. Open one and you are in a room with whoever else is playing.
A chaotic 1v1 duck tank duel in a maze filled with witches, lemons and falling blocks.
All of it is on every plan, the free tier included. The plan changes how much you get, never which parts.
Priced on monthly active players, the one number you can predict for your own game. A traffic spike costs nothing extra. Every plan has every feature: paying raises the limits, it never unlocks a capability.
$0
Everything works. Enough room to finish a game and share it.
Start free$15/month
For a game that found an audience. Every feature, more of it.
Start free$59/month
A game with real traction, and the headroom to keep it.
Start free$199/month
A catalogue of games, a team to run them, portal-scale traffic.
Start freeAnnual billing is ten months for twelve. The full limit table, including saves, bandwidth, history and player-made items, is on the pricing page.
I've been programming multiplayer games for over ten years, and the technology was always the hard part. I built Multiplayer Agent so it finally isn't: create any game you want, tell your AI agent to hook up to the MCP, and the backend you used to stress about is just done.
Build that game you've always wanted to build, share it with your friends, and have fun. You own the code. Now get out there and make something awesome.
Read the full storyThe free tier does not expire and does not ask for a card. Build the whole game, share it with a friend, and only think about a plan once real players turn up.