Step 3.3 - Settings -> Inventory Settings

Notecards:

The bot can accept inventory items for different reasons.
Notecards are a bit special, since they are used to send group advertisements.

The default setting is to only accept notecards from the master and operators (if operators group is used).
If you change this setting to "AutoAccept", the feature to send group advertisemens using notecards will be disabled.
This is to make sure that your bot won't spam it's groups just because someone sends it a notecard.

The default setting is to only accept from master and operators. 

Other Inventory Items:

Other inventory items, such as objects, folders, landmarks etc. is automatically accepted bases on these settings.
Set to "AutoAccept" to automatically accept any incoming inventory offer (except notecards), or set to "Accept from master and operators only" to avoid accepting inventory offers from random avatars.