A new series of generalist AI agents called Holo4 has emerged as a cost-effective competitor to frontier models, delivering strong performance on complex automation tasks across multiple software interfaces. The models come in two sizes—27 billion parameters and a 35-billion parameter Mixture of Experts variant—and are designed to interact with applications through graphical interfaces, code execution, APIs, and Model Context Protocol tools without requiring separate models for each interface. Trained on real-world business tasks through supervised and reinforcement learning, Holo4 powers workflows ranging from desktop applications to web platforms and backend systems, with availability through the H Models API. On the OSWorld 2.0 benchmark for long-horizon desktop control, Holo4-27B achieved 61.7 percent accuracy against OpenAI's Opus 5.5 at 81.8 percent, while delivering dramatically lower costs per task. The company also released Holotron4 Nano as an updated smaller model in the family. Performance on API-calling benchmarks similarly positions Holo4 as competitive with both proprietary and open-weight alternatives, addressing enterprise demand for cost-efficient agentic AI capable of handling diverse real-world business processes.