Raids are loud and fast. The useful part of a mod bot is noticing the pattern before your team has finished reading the first spam wave.
What triggers an alert
Sift watches join rate: too many accounts in a short window and your log channel gets a raid alert, with how many joins happened and how many accounts look brand new. You decide the numbers in /settings.
Optional auto-lockdown
If you opt in, Sift can lock text channels when a raid is detected. That is a big hammer, so it is off by default. When you run /lockdown to undo it, Sift puts each channel's send permission back the way it was, so read-only channels stay read-only. Slowmode isn't touched either way.
Whole-server scope
/lockdown scope:Whole server locks or unlocks everything in one go. Useful when you are mid-raid and do not have time to click twenty channels.