Merlin is an AI-powered Chrome extension and web app that serves as a versatile assistant for various tasks, such as researching, writing, summarizing, coding, and more. It integrates with multiple AI models, including GPT-4, Claude, and Llama, allowing users to access AI features directly on their favorite websites. Merlin supports over 25 languages and offers specific tools for different professional roles, such as entrepreneurs, researchers, marketers, educators, students, copywriters, developers, analysts, and customer support agents. It provides both free and premium plans, with the premium offering enhanced usage limits and team features.