Trigger expression with boolean values

[Bubbagump]

This seems like an extremely simple task, but I am flummoxed. I am using the HTTP agent to monitor an endpoint that returns JSON. I have the pre-processing working such that the value I want is being monitored. 1 = good 0 = broken. This shows up perfectly well in Latest Data when I test and graphs all work. Now I want to make a trigger that says if the value of this item = 0 for more than 15 minutes, do a thing. I have been trying to get this to work with last() with no luck. Last() is always triggering after 1 minute. I have tried

{SomeHost:SomeCheck.last(15)}=0

which still triggers at one minute.

{SomeHost:SomeCheck.last(#15)}=0

seems wrong based on the docs saying

"Last(#3) - third most recent value (not three latest values)"

Any help is greatly appreciated.

[Bubbagump]

Ah, max() seems to work a treat. Thank you!

Should I understand that any where I see

sec or #num - maximum evaluation period¹ in seconds or in latest collected values

I can use m, h, d in the function as well?

[Bubbagump]

Derp, I see now in the footnote

3) For all trigger functions sec and time_shift must be an integer with an optional time unit suffix and has absolutely nothing to do with the item's data type.