Facebook users who are nervous about unwittingly excluding friends from their events now have access to a third-party Facebook application that may be able to quell their fears.

Who Did I Forget is quite simple to use: After granting permission for the app to access a user’s Facebook account, it lists events the user has organized or is invited to.

Clicking on the event brings up a list of the user’s friends who are already on the guest list.

Should the user choose to expand this list, he or she can type in the name of a specific friend, and the app will populate the guest list with mutual friends and connections.

Who Did I Forget was developed by French PhD student Adrien Friggeri.

Thanks to Steve Allard of Wise Metrics for the tip.