What it is The code diff sidebar is a dedicated sidebar in OpenAI's Codex app that shows code diffs — a visual comparison of code changes. It is aimed at people who prefer reviewing changes visually rather than reading raw text[^LfPNaoYMaRY@294]. Where it fits The Codex app is a graphical command center for agents — deliberately neither a terminal nor an IDE[^LfPNaoYMaRY@102][^LfPNaoYMaRY@124]. The diff sidebar is one of its review-oriented surfaces, sitting alongside threads, workspaces, and skills as part of managing agent work. In review workflows it acts as a safety net for code review: when an agent produces changes, you can inspect them visually before accepting[^LfPNaoYMaRY@294]. Explore further [moment: 294] jumps to the part of the walkthrough that introduces the sidebar. <KeyPoints.Item>A dedicated sidebar in the Codex app that displays code diffs visually[^LfPNaoYMaRY@294].</KeyPoints.Item><KeyPoints.Item>Built for people who prefer visual code comparisons over raw text[^LfPNaoYMaRY@294].</KeyPoints.Item><KeyPoints.Item>Serves as a safety net for code review of agent-produced changes[^LfPNaoYMaRY@294].</KeyPoints.Item>