Abstract: In a computer-implemented method, a digital content item to be tested is received. A display of a visual representation of the digital content item is simulated, where the visual representation is selectable and the digital content item is associated with a code snippet that is executed when the visual representation is selected. A simulated user click on the visual representation is received and the code snippet is executed in response. Processing actions of the code snippet are monitored, and it is determined whether the processing actions violate one or more predetermined system policies indicative of a content item unsuitable for service. A score for the code snippet is calculated based on one or more violations of the one or more predetermined system policies. The digital content item is suspended to prevent service of the digital content item if the score exceeds a predetermined threshold score, and validated for service otherwise.