Open Source GPT Projects
GPT, or generative pre-trained transformer, describes a family of language models that predict and generate text using patterns learned from large datasets. GPT-based systems can draft and summarize content, answer questions, translate text, and support conversational interfaces. They help automate language tasks and make it possible to build applications that work with natural-language input and output.
Open source tools in this area include model implementations and checkpoints, fine-tuning and evaluation utilities, inference servers, and frameworks for building applications around models. When choosing one, consider its license, model requirements, maintenance activity, performance, and compatibility with your data, hardware, and deployment environment. These tools are useful to developers, researchers, and organizations that want to experiment with language models or integrate text generation into their own systems.
3 repositories · updated March 1, 2026
Helicone: Open Source LLM Observability Platform and AI Gateway
Helicone is an open-source LLM observability platform and AI Gateway for AI engineers. It provides one-line code integration to monitor, evaluate, and experiment with large language models, offering features like cost tracking, prompt management, and intelligent routing. The platform supports a wide range of inference providers and frameworks, simplifying LLM development and deployment.

lagent: A Lightweight Framework for Building LLM-Based Agents
lagent is a lightweight, open-source framework developed by InternLM, designed for efficiently building large language model (LLM)-based agents. It provides a PyTorch-inspired design philosophy, making it intuitive for developers to create and manage multi-agent applications. This framework simplifies the process of agent communication, memory management, and tool integration.

GraphRAG: A Modular Graph-Based RAG System for LLM Discovery
GraphRAG, developed by Microsoft, is a powerful and modular graph-based Retrieval-Augmented Generation (RAG) system. It is designed to extract meaningful, structured data from unstructured text using Large Language Models (LLMs). This system enhances an LLM's ability to reason about private and narrative data by leveraging knowledge graph memory structures.