OpenAI Open-Sources Codex Harness: Boosts AI Agent Dev

OpenAI has open-sourced its Codex Harness framework, providing developers with the core engine to build AI agents. This framework includes three open-source components: a CLI tool, an SDK, and an app-server. These support features like persistent conversations and real-time streaming. Tests show that with Harness optimization, the GPT-5.6 Sol model's score on a benchmark increased from 13.3% to 38.3%, while token consumption dropped sixfold. Practical uses are already happening, like Thrive Holdings processing tax forms and Cisco's Cloud Manager. This move aims to embed AI capabilities directly into various business tools, moving beyond traditional chat interfaces. It means developers can integrate powerful AI agent loops into their own products, controlling their interface, data, and permissions. This could significantly change how software is developed.