LlamaIndex.TS is a newly launched TypeScript-centric library designed to facilitate the integration of private data with large language models (LLMs), addressing the common limitation of LLMs like ChatGPT, which cannot access proprietary or user-generated data. Developed with the aim of being the most user-friendly and robust solution for working with data in LLMs, LlamaIndex.TS was inspired by interactions at an Emergency ChatGPT Hackathon and offers a streamlined design that loads data into a standardized format to create a knowledge base, which is then used to enhance queries to LLMs. The library differentiates itself from its Python counterpart by utilizing camel-cased function names, simpler prompt interfaces with native JavaScript template literals, and a preference for interfaces and plain old JavaScript objects (POJOs) instead of classes. It currently supports NodeJS v18 and above, with future expansions planned, and encourages contributions to expand its core features and integration capabilities.