OpenAI Releases GPT-6 Model Guide with Enhanced Prompt Caching for Long-Running Agents

OpenAI has published a comprehensive guide for its GPT-6 model family, featuring three distinct models optimized for different workloads and introducing major improvements to prompt caching that reduce costs by up to 90% for long-running tasks. The guide, released October 2, 2026, provides practical recommendations for model selection, cost management through caching, and managing agents that operate continuously for hours or days.