First, it’s very cute. I purchased this to keep my new baby chickens separate from the main flock until they were old enough.  It works for that. I do not think it would work for more than 2 full grown chickens and only for a short time (like quarantine) b cause it’s quite small. 
Second, it would not keep a determined Fischer cat out but other animals might be deterred. It moves easily so I placed a cinder block to prevent a raccoon or similar from lifting it and getting in that way. The roosting bar is VERY low. They all ended up sleeping in the nesting boxes.  
It worked well for what I needed it.