Mac OS X launchd: forbid starting a process in Power Nap (dark wake)?

What would be the best way to forbid Mac OS 10.10+ Launchd to start a Bash script when a MacBook is in Power Nap (dark wake)?

Is there an elegant way to limit it only to "real wake", like:

<key>RunOnlyWhenInRealWake</key><true/> ?

I haven’t found anything specific in the Apple docs

I have a bash script which sometimes executes in Power Nap and has no time to finish before Mac OS goes back to sleep.

I’ve tried prepending a sleep 15 timer to the script… would like to avoid having to lengthen that to, say, 5 minutes.

Thanks!

(moved the original question at Stack Overflow here after Matteo's suggestion)