The authentication server is required to implement [Yggdrasil Server Specification](https://github.com/yushijinhun/authlib-injector/wiki/Yggdrasil-%E6%9C%8D%E5%8A%A1%E7%AB%AF%E6%8A%80%E6%9C%AF%E8%A7%84%E8%8C%83).
Configure Minecraft server with the following JVM parameter:
```
-javaagent:{/path/to/authlib-injector.jar}={API Root of Authentication Server}
```
## Debug
### Print verbose logs
Add the following JVM parameter:
```
-Dauthlibinjector.debug={types of logs to print}
```
Types of logs:
*`launch` startup of authlib-injector
*`transform` bytecode modification
*`config` configuration fetching
*`httpd` local http server (The local http server acts as a reverse proxy between client and the remote authentication server, which allows authlib-injector to implement enhancements.)
*`authlib` logs intercepted from authlib (which contains detailed network communication)
Use `,` as the separator when specifying multiple types. To print all the logs, set the type to `all`.
### Dump modified classes
Dump the modified classes to current directory with the following JVM parameter:
