Howdy! I like using CAT Shards's unassigned.reason as reference, but just ran into an undocumented one and realized the code includes a couple others as well.

Can you append info on these

• PRIMARY_FAILED
• FORCED_EMPTY_PRIMARY
• MANUAL_ALLOCATION
• INDEX_CLOSED
• NODE_RESTARTING

I'm not sure if you're prefer a literal code copy/paste, but am experiencing MANUAL_ALLOCATION if you have more information on it. Cheers!