Using PLANS.md for multi-hour problem solving | OpenAI CookbookOct 7, 2025Using PLANS.md for multi-hour problem solving Codex and the gpt-5.2-codex model (recommended) can be used to implement complex tasks that take significant time to research, design, and implement. The approach described here is one way to prompt the model to implement these tasks and to steer it towards successful completion of a project. These plans are thorough design documents, and "l
