This Citi Executive AAdvantage MasterCard link is showing a sign-up bonus of 100,000 American Airlines miles after you spend $10,000 within the first 3 months of opening. There is also a $200 statement credit (earn $1 in statement credits for each $1 spent on purchases within the first 12 months.) There is a hefty $450 annual fee that cannot be waived, so you should be sure that you can get proper value out of those miles. In addition, the primary benefit of this card over lesser AA cards is that you get access to their airport lounges (Admirals Clubs).
The offer appears targeted, but the agent code is not required and people have gotten approved for the card. That doesn’t necessarily mean you won’t have some trouble getting the 100k bonus, so I would take screenshots or save all application pages to PDF format along the way.