An Action List Reminder is an email notification that something is going on with a proposal in Kuali and you’re somehow involved. Currently Action List Reminders don’t tell you what needs to be done. They’re more like a “ping” to let you know something’s coming (or going). You have to log into Kuali and view the record to figure out what's needed (if anything).
When a proposal is submitted into signature authorization routing, Kuali emails notifications to signing officials, their alternates (back-ups), and other users who need to stay informed about the progress of the proposal.
The most important things to note in an Action List Reminder are the elements highlighted in this screenshot:

The “Document ID” is the number used for taking needed ACTION, such as approving a proposal.
The information to the right of “Title” includes more than just the proposal title. The “Proposal No” is the permanent proposal record number, and the PI’s name is listed at the end.
Similarly, the information to the right of “Sponsor” includes more than sponsor name. At the end is “Due Date” that that proposal must be submitted.
The rest of the message can only be used if you scrape (i.e.: copy) and paste the URLs into your browser. It’s not ideal and an enhancement is currently under development for expected 2017 release.