Why was the Writ of Assistance created?

Answer 1

This was a general search warrant issued by the British government that gave customs agents the right to search any building or ship in the colonies for smuggled goods.

In current usage:

In criminal law - A writ of assistance is a court order to a law enforcement officer to enforce a prior order of the court.

In civil law - In bankruptcy law, a writ of assistance is an order directing that a party convey, deliver, or turn over a deed, document, or right of ownership.

Answer 2

to stop smuggling in the colonies