The gotcha for this is that you have to actually use the resources on your free instance or they will reclaim it. I use my instance as a Minecraft server so it utilizes about half of the 24GB RAM you get. For a very light compute task like a chat bot, it might be difficult to keep the instance from being reclaimed.

From this page:

Idle Always Free compute instances may be reclaimed by Oracle. Oracle will deem virtual machine and bare metal compute instances as idle if, during a 7-day period, the following are true:

CPU utilization for the 95th percentile is less than 15% Network utilization is less than 15% Memory utilization is less than 15% (applies to A1 shapes only)

Pretty rich coming from the guys who overly moderate players’ private Minecraft servers up to and including banning players for saying a no-no word…

Note that these are just quotes from the disastrous AMA he held last week, not new comments that have been made.