Understanding Server-to-Client Config Sync (Why Some Options Are Greyed Out)

What Synchronization Does

Configuration API can automatically push server-side config values to every connected client. Mod authors enable this by marking a field with @Configurable.Synchronized. When a player joins a server, those marked values are sent from the server and applied on the client.

This matters because many options affect gameplay logic that must match on both sides. If the server says a feature is off, your client cannot simply turn it on locally.

Why an Option Is Locked

If an entry is greyed out, read-only, or snaps back after you change it, it is almost certainly a synchronized value controlled by the server. You cannot override it from your own config screen while connected.

Things to check:

• Are you in a singleplayer world? Then you are the server, and you can edit synchronized values freely.
• Are you on a multiplayer server? The server operator controls those values. Ask them to change the server config.
• Did you just change a value and it reverted? That is the sync overwriting your local edit on the next update.

Practical Tips

Edit synchronized options while in singleplayer or before hosting, then copy the resulting config to your server if you run one. On a multiplayer server, treat locked entries as informational — they tell you how the server is configured, not something you can change.