OpenAI released GPT-5.1, enhancing speed and efficiency for coding and agentic tasks. The model adapts its reasoning based on task complexity and introduces new tools like `apply_patch` for code editing and a shell tool for command execution. Developers can leverage extended prompt caching and a "no reasoning" mode for faster responses.

This article provides guidance on optimizing the Codex model for coding tasks using the API. It covers recommended practices for prompting, tool usage, and code implementation to enhance performance and ensure efficient task completion.