It allows you to select any quest you want and that quest will automatically be picked up and turned in.
How to use:
Open dialog with any NPC that has your quest;
Type /expaq print
This will list you all the quests that NPC has and their ids.
/expaq add questId to add that quest
/expaq remove questId to remove that quest
/expaq print will show you all quests currently added when you type this and are not talking to an npc.
/expaq on and /expaq off to turn it on and off as you desire