Licensing your game
What other people may do with something you publish here. You choose it, you can leave it alone, and the default is the safe one.
- 5 options
- You keep your rights
- Shown on your game
What this decides
When you publish a game here you are asked one question: what may other people do with it? That is all a licence is. It is a message from you to everyone else who sees your game, and it appears on the game itself so they can read it.
You do not have to think about it. Leaving it alone means all rights reserved — nobody may reuse your game, which is the same position you would be in anywhere else, and the right answer if you are unsure.
This is not the agreement between you and us
This is separate from the permission you give us to run the platform. Whatever you choose here, we can still host your game, show it in the feed, and keep it playable — that comes from the Creator Terms, not from this setting.
That permission is in the Creator Terms, which you accepted when you first published. Your licence choice never affects it, and it never affects your licence choice.
One thing worth knowing first
A game here is one HTML file, and the browser has to be given it in order to run it. So your game’s code is already readable by anyone who plays it, whichever licence you pick.
This surprises people, so it is worth being plain about what follows from it. Choosing “all rights reserved” does not make your code secret — it means nobody is allowed to reuse it. Choosing “source available” does not reveal anything that was hidden — it grants permission to learn from what is already visible. The choice is about permission, never about disclosure.
The options
Five, ordered from most protective to least. Each one is shown on your game so players and other creators can see what you are offering.
All rights reserved
DefaultNobody may reuse your game. People can play it here; that is all. This is the default and it is the safest choice if you are unsure.
Source available — read, but do not reuse
People may read and learn from your code. They may not reuse or republish it. Worth knowing: your code is already readable by anyone who plays the game, so this grants permission rather than revealing anything.
Creative Commons BY 4.0
Cannot be undoneAnyone may reuse and adapt your game, including commercially, as long as they credit you.
Creative Commons BY-SA 4.0
Cannot be undoneAs BY 4.0, and anything built from your game must carry this same licence.
CC0 1.0 — public domain
Cannot be undoneYou give up your rights in the game as far as the law allows. Anyone may do anything with it, without crediting you.
Before you pick one of the open ones
3 of the 5 — CC BY 4.0, CC BY-SA 4.0, CC0 1.0 — public domain — cannot be taken back. We ask you to confirm those a second time, and these are the two sentences that confirmation shows you:
It is permanent
This cannot be undone. You can stop offering this licence on future versions, but anyone who has already relied on it keeps that permission permanently.
It has to be yours to give
Only choose this if you own everything in the game. Fonts, sprites, sound effects and music are often licensed to you personally and are not yours to re-license to other people.
That second one catches more people than the first, because a game is usually assembled from things its author did not make. A font, a sprite sheet, a sound pack or a music loop is often licensed to you personally — enough for you to ship a game with it, and not enough for you to hand it onward to everybody else.
Where to set it
You are asked when you upload a game, and you can change it afterwards on the game’s own settings under your games. Changing it applies from that moment onward — which for the irrevocable options means new readers only, never the ones who already have it.
If your agent built the game
Set it yourself. A game submitted through the MCP server arrives with no licence on file, which displays and behaves as all rights reserved — there is no tool for an agent to choose one, deliberately, because it is not an agent’s decision to make about your work. An agent can read the licence back with get_game, so it can tell you what a game currently says.