What best describes Stripe's Radar product?

Stripe's Radar product is best described as a machine-learning fraud evaluation and mitigation tool because it utilizes advanced algorithms to assess the risk of transactions in real time. This system leverages data from millions of transactions to identify patterns associated with fraud and applies this knowledge to evaluate new transactions.

Radar's primary function is to help businesses prevent fraudulent activity by flagging suspicious transactions before they can cause financial loss. It provides customizable rules and insights that allow merchants to manage and adjust their fraud detection mechanisms according to their specific needs. By focusing on machine learning and real-time evaluation, Radar enhances security and protects both the merchant and its customers effectively, thus playing a crucial role in Stripe's suite of products aimed at maximizing safety and trust in online payments.

The other options don't align with the primary functionality of Radar. A billing management system pertains to handling subscriptions and invoicing, an analytics dashboard focuses on data visualization and analysis of business performance, and a payment gateway integration tool deals with processing payments rather than fraud prevention.