The Aggregation Pipeline Builder is a new tool released by MongoDB for its Atlas platform, allowing developers to quickly and easily explore and refine aggregation queries through a simple user interface. This builder enables developers to learn, test, and visualize the power of MongoDB's aggregation framework without writing code, saving hours of trial and error. With features like drag-and-drop stages, code skeletons, and preview mode, more developers can take advantage of the rich query capabilities of MongoDB. The Aggregation Pipeline Builder makes MongoDB Atlas a valuable tool for improving developer productivity, and is easily accessible under the Collections view of a cluster. It offers several features that make it easy to learn about aggregations, including a drop-down menu of available pipeline stages, code skeletons, and auto-completion for operators and document field names. The builder allows developers to test and debug long and complex aggregation queries directly in their browser, with an auto-preview feature that ensures the output can be seen without taxing the cluster with data-intensive queries.