Combine the canola oil, ranch seasoning, red pepper flakes, garlic powder, onion powder, and dried parsley in a bowl. Mix until well combined.
Place the oyster crackers into a large zip-top bag.
Pour the oil and seasoning mixture over the crackers in the bag.
Close the bag securely and gently tumble and shake until all the crackers are evenly coated with the seasoning.
Arrange the seasoned crackers in a single layer in the air fryer basket. Work in batches if necessary.
Air fry at 300°F (150°C) for 5 minutes, then shake the basket.
Continue to air fry at 300°F (150°C) for another 2-5 minutes, or until golden brown and crispy.
Let cool slightly before enjoying.