Many shredders can cut through staples and paper clips, however, it is advisable to remove them first since metal dulls the shredder's blades, and if the shredder needs repairing, documents in need of shredding accumulate and become a potential security risk.
Adhesive or sticky paper can lead to paper jams which will bend the teeth of the shredder.
In the event of your shredder's motor overheating, turn it off for at least 15 minutes, allowing the motor to cool down before using the shredder again.