They have rest cycles
Tarantulas spend long periods inactive and show daily activity patterns, but describing this as human-like sleep can be misleading.
Stillness is normal
Healthy tarantulas may sit in one position for hours or days. Judge health from posture, hydration, body condition and recent behaviour.
Many are more active after dark
Some species emerge or web more when the room is quiet and dark, especially arboreal and fossorial animals.
Premoult can look like extra rest
Reduced movement and hiding often increase before a moult. Combine behaviour with feeding history and abdomen appearance.
Do not poke to test life
Repeatedly touching a still spider causes unnecessary stress and can provoke defensive behaviour. Observe posture and gradual movement instead.
Know the abnormal signs
A sustained death curl, severe dehydration or inability to stand differs from ordinary stillness. Learn the posture rather than judging activity level alone.