Sphinx, an open-source Git hook, quizzes you on your agent's diff before the push goes through

After npm install -g sphinx-understand and sphinx install, pushes to protected branches pause while a separate reviewer model reads the diff and asks what the change does when things fail, and the push only continues once you answer correctly. It works with Codex, Claude Code, Cursor, OpenCode, Pi, or plain Git, and sphinx yolo skips the check but logs every skip (HN thread).