Thank you all for the suggestions. I finally got a chance to get back to working on this today - been a busy week!
I have tried various iterations of the memo variable in the URL to no avail. GentlePumpkin, to answer your questions:
1. Ist BI on port 81?
Yes, and Deepstack is on Port 83
2. {user} and {pw} need to be replaced, but not [summary]
Confirmed
3. I'm not quite sure, but it could be that there must be at least a few milliseconds between creating a trigger and tagging it with memo=[summary]. So triggering and adding the summary must happen with two subsequent url calls
Not sure I followed this. Are you suggesting that the delay between trigger and tag would generate the 2 URL's, or that I NEED to create 2 URL's? How can I go about checking to see if this is happening?
I don't know if this is related to this or not (triggering delays) but it seems that one of my cameras will only randomly generate the alarm clip in BI. It shows up in the AITool history, but I will only get the clip in BI maybe 1 out of 10 times (seems random though). The URL is configured the same as the other cameras, and I keep checking BI to see if something is configured differently for that camera, but I can't seem to see any differences.
Thanks again for everyone's help!