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OpenAI's official guide to configuring Codex code and security reviews for GitHub pull requests, including automatic reviews and custom repository instructions.
A hands-on write-up of wiring Google's open Gemma 4 model into the Codex command-line coding agent so it runs locally instead of calling a hosted API.
From the site: I wanted to know whether Gemma 4 could replace a cloud model for my day-to-day agentic coding. Not in theory, in practice. I use Codex CLI…
Why I recommend it: Useful if you want to try coding agents without paying per token — local models are slower, but free and private.
XDA Developers had Claude Code (Opus 5), Codex (GPT-5.6) and Google Antigravity (Gemini 3.8) rebuild the same website from the same brief. The comparison shows which agent handles detail, polish and real-world edge cases best.
Why I recommend it: Useful if you are choosing an AI coding assistant for side projects or learning to prompt more effectively. The winner is not necessarily the one you would expect.
