Simple Rules is a very easy to use rules plugin for your spigot server!

Commands:
/rules - view the list of rules
/rulesaccept - accept the rules
/rulesdeny - deny the rules
/simplerulesadmin - opens the admin panel

Permissions:
simplerules.use - Allows the player to use the /rules command
simplerules.rules.accept - Allows the player to use the /rulesaccept command
simplerules.rules.deny - Allows the player to use the /rulesdeny command
simplerules.admin - Allows the player to use the /simplerulesadmin command
simplerules.rules.bypasswelcomemessage - Bypasses the welcome message for players that have already agreed to the rules