DAI Engine 4.1

Server authority

• Clients request authoritative actions; the server validates identity, capability, permission and scope.
• Skills use secure-by-default flags.client_callable.
• Open-to-LAN guests no longer inherit host/Creator authority.
• Vehicle input is finite/clamped/rate-limited and resolved against the server-known ridden vehicle.

JSON owns presentation + gameplay mapping

• Built-in reaction-event definitions are fallback hook bindings and can be replaced, disabled or remapped by datapacks.
• Screen overrides support replace, skin, overlay and hide.
• Data screens can disable/recolor/reposition the default panel, border and title and use fullscreen scenes.
• Generic actions open_screen_class, open_shell_stage and reload_presentation remove dependencies on specific hardcoded DAI menus.

Dedicated servers + Creator

• Supported datapack presentation/reaction JSON is synchronized to clients for the active server session.
• The web Creator exposes the 4.1 reaction-event, data-screen, screen-override and skill schemas.
• Current APIs are available at /dai/api/capabilities-4.1.json, /dai/api/guides-4.1.json and /dai/api/packs-4.1.json.

Version jump