Configuration API Wiki › FAQ
Configuration API FAQ
10 questions players actually ask, answered.
How do I open a mod's config screen in-game?
Open the Mods menu, then click the Config button next to the mod (Forge/NeoForge) or use ModMenu and click the config icon on the mod's entry (Fabric). The screen opens with Header, Content, and Footer sections for editing that mod's options.
Why is the Config button missing for some mods?
Only mods that actually use the Configuration API and register a config screen will show a Config button. If a mod has no config or doesn't use this API, there's nothing to open, so no button appears.
Why are some options greyed out and I can't change them?
Those options are server-synchronized, meaning the server's value overrides yours while you're connected. Disconnect from the server (or change them in singleplayer) to edit them, since the server pushes its values to clients on join.
What does @Configurable.Synchronized actually do?
It marks a config field so the server automatically sends its value to every connecting client. Clients then display and use the server's value instead of their own local one, which is why the option becomes read-only in-game.
How do I edit a config file by hand?
Find the mod's config file in the config folder, which may be YAML, JSON, or Properties depending on the mod. Open it in a plain text editor, change the values, save, and restart the game or reload so the changes take effect.
My config file got corrupted and the game won't start — how do I fix it?
Delete or rename the broken config file and let the mod regenerate a fresh one with defaults on next launch. If you only made a small mistake, you can also restore the value you changed by hand instead of deleting the whole file.
How do I reset a config back to its default values?
Delete the mod's config file and restart so it regenerates with defaults, or use the reset option in the config screen if the mod provides one. Either way, any custom values you set will be lost.
Can I change server-synced options on a multiplayer server?
No — synchronized options are controlled by the server and pushed to clients, so you can't override them locally while connected. Ask the server admin to change them in the server's config instead.
Do I need ModMenu to use the config screen on Fabric?
Yes, on Fabric you need ModMenu installed to reach the config screen from the Mods menu. On Forge and NeoForge the Config button is built into the Mods menu, so no extra mod is required.
Does this API add much lag or affect performance?
The API itself is lightweight — it mainly reads config files at startup and syncs values on join, so it shouldn't noticeably affect performance. Any lag you see is more likely from the individual mods using the config, not the API.