Sphinx is a Git hook for agent-assisted development that pauses a push to ask a question about the code being changed. A separate review process reads the diff and asks how the change behaves, including what may happen when something goes wrong. The developer answers before the push continues, making understanding part of the workflow rather than leaving it until a later code review.
The tool can work with an existing coding agent, OpenRouter or an OpenAI-compatible endpoint. The project lists support for tools including Codex, Claude Code, Cursor, OpenCode and Pi, as well as ordinary Git use. Installation uses the sphinx-understand package and requires a supported Node environment on macOS, Linux or WSL. A bypass mode is available, with skipped checks logged rather than presented as completed understanding checks.
