This is an API for developers to help them creating titles,subtilels and actionbar messages, there are no test commands.
Just drag the jar in your plugin directory and reload your server If you want to use the api you need to go to your javabuild path and add the jar to the list and you are good to go :)
Setting a title
boolean TitleActionBarAPI.sendPlayerTitle(player, fadeIn, stay, fadeOut, Title);
Setting a subTitle
boolean TitleActionBarAPI.sendPlayerSubTitle(player, fadeIn, stay, fadeOut, subTitle);
Setting an action title
boolean TitleActionBarAPI.sendPlayerActionbar(player, text);
Setting an full title
boolean TitleActionBarAPI.sendFullTitle(player, fadeIn, stay, fadeOut, title, subtitle);
none
If you find some pls write a comment down below