Real buyers tend to show consistent signals like add-to-cart actions, checkout starts, and completed payments rather than just browsing. Compare conversion rate after click across toolbar and premium cohorts, not just CTR, to spot inflated or low-quality traffic. You can also look at session depth, time on page, and repeat visits to see if intent persists beyond the first click. If toolbar traffic drops off quickly or shows high bounce, it's likely low-intent or non-human activity.