Most people discover LoopBack when they are staring at a list of UI notes they have been putting off. The spacing is off on mobile, the focus ring is missing on a button, the error state shows the wrong icon. Small things that individually take longer to log than to fix, but collectively they accumulate until someone schedules a dedicated polish sprint. LoopBack turns that sprint into a ten-minute session.
The workflow starts with opening your app on localhost in Chrome with the LoopBack extension active. You click the extension icon, which overlays a subtle annotation layer on the page. Clicking any visible element opens a comment input. You type a short note describing what is wrong, hit save, and LoopBack does the rest: it captures the element's CSS selector, takes a screenshot of the current viewport, records the page URL and screen dimensions, and stores everything locally.
You repeat this for every issue you find. There is no context switching, no filing tickets, no waiting for screenshots to upload to a project management tool. You move through your UI the way you would during a normal review session. The difference is that LoopBack is silently accumulating structured data behind every note you drop.
When your list is complete, you open the LoopBack drawer and press the export button. LoopBack formats every annotated item into a single prompt block. Each item includes the original comment, the CSS selector with a human-readable description of the element, the absolute path to the saved screenshot, the viewport dimensions, and the page URL. The prompt is structured so that an AI agent can work through it item by item without needing to ask clarifying questions.
You paste the prompt into Claude Code, Cursor, or any agent that accepts text input. The agent reads each item, locates the element using the selector, cross-references the screenshot, and applies the fix. Because every piece of context the agent needs is present in the prompt, you rarely need to clarify anything. When the agent is done, you switch back to LoopBack, trigger a retest, and mark each item resolved or reopen it for another pass.
The total time from starting an annotation session to watching the agent begin its first fix is typically under fifteen minutes for a session with ten to fifteen issues. That includes the time to annotate, export, and paste. What used to be a multi-day back-and-forth between design and engineering becomes a single focused loop.