Here is the full list of all 16 Claire achievements.
Answer the phone.
Find 3 notes.
Have maximum panic.
Unlock the ending.
Unlock the ending on Nightmare.
Unlock the Good ending.
Unlock the Dog ending.
Defeat the Glower.
Find each delinquent scene.
Find 3 butterflies.
Find all butterflies.
Find all notes.
Make it to the school.
Find 80 items.
Unlock the otherworld scene.
Make it to the apartments.