lxi.ai is a custom question answering tool that uses OpenAI's GPT model to provide trustworthy answers based on information in a user's own documents. Users can upload PDFs, import webpages, and add text directly to build a library of documents. When a question is asked, lxi.ai retrieves relevant paragraphs of information from the library and condenses them into a concise and factual answer. A 14-day free trial is available, with usage-based pricing after the trial has ended.