Web multiplayer

Usage guide: choosing the network model of a web game (claim, authoritative, rollback, state and config.net {model, sync, physics}), keeping it playable alone, opening a room at /play/online/host/<project>?players=N, inviting the other players, previewing and testing before sharing, errors.

Source: module-kits:kits/net/usage/web-multiplayer/en.mdView Markdown source

Also read offline — CLI: grip-forge docs web-multiplayerMCP tool: gripforge_docs { "topic": "web-multiplayer" }

Multiplayer web game on the kits (rooms and invitations) #

How to turn a game built on the Game Kits into a web game several people play together: pick the network model, open a room, invite the other players, check it. Readable offline: gripforge docs web-multiplayer, or the MCP tool gripforge_docs (topic web-multiplayer). The kits and their settings are in gripforge docs net.

1. Choose the model #

Install one sync kit; it is the network model of the game (gripforge docs net has the table):

gripforge_gamekit_install { project_id: "gkp_…", id: "net.claim" }   # brings net.transport

Model	Pick it when	Notes
`net.claim`	co-op, sandbox, cars, anything where your own avatar must answer at once	each client simulates what it owns; the server arbitrates; not for competitive play
`net.authoritative`	shooters, economies, rankings	the server simulates; clients predict; costs server CPU
`net.rollback`	duels, small deterministic arena games	inputs only; needs a deterministic simulation
`net.state`	cards, boards, turn games, hidden information	rules are data, validated on the server

For a vehicle game (an arena with cars and a ball, a kart race) start with net.claim; for physics shared between peers add net.physics and set the sync kit's physics to shared. The room reads the model, the sync settings and the physics settings from the project (config.net = { model, sync, physics }); change them with gripforge_gamekit_configure, never in the room.

2. Keep it playable alone #

The audit flags common.network_optional when a sync kit is installed and nothing lets one player play without a server. Add coop.session (role solo) or a solo entry in the menu; the room is the way to invite others, not the only way to start.

3. Open a room #

Open this address on the GripForge site, signed in to the workspace that owns the project:

/play/online/host/<project_id>?players=4

players is the number of seats (2 to 16; default 2). The page creates a private room for the project (the server is gfnet-server with the project's model), starts it, makes one personal invitation per other seat, and shows them as links. Press Play to enter the game with your own seat: the game's menus and lobby run as in any other session. The link of the room is /play/online/<room_id>#<key>; the key stays in the fragment, is used once and is not kept in the address afterwards. Invitations last four hours. Opening a room needs the editor or owner role of the workspace.

Through the API: POST /api/v1/network/rooms { projectId, minPlayers, maxPlayers, requireReady }, then POST /api/v1/network/rooms/<id>/start, …/invitations { role: "player" } for each invitation, …/redeem { token }.

4. Invite and check #

Send each link to one person; every link is one seat.
To look at the game alone first, gripforge_game_play_url returns the project's play address (the solo preview); share it as finished only when gripforge_game_audit says complete and gripforge_validate_release says ready.
Run gripforge_game_test before inviting anyone: the automatic player drives a vehicle with the throttle and steer inputs of the game as a person would, and reports a game that cannot start alone.

Errors #

You see	Cause	What to do
`not_networked`	the project installs no `net.claim` / `net.authoritative` / `net.rollback` / `net.state`	install one sync kit
`This game has no net.transport kit`	a sync kit without its transport	install `net.transport`
The service of rooms does not answer	the runtime of the rooms is offline	retry; rooms can still be prepared
`invalid_net`	a hand-made room whose `net.model` is not a string	pass `{ model, sync, physics }` or use a project