TDD Guard was built when Claude Code was the only one to offer hooks. Plugins didn't exist and the models were weaker, so the validation context and instructions took more work to get right. This is why it ended up requiring test reporters for different languages.
I have started a new project that does the same TDD enforcement, also through hooks, but without reporters. It works with any test runner, and it is vendor-agnostic, it works with Claude Code, Codex, and GitHub Copilot. The validator also sees recent session history which helps it handle cases like refactoring better.
The TDD instructions are still pretty basic compared to TDD Guard's, which have been dogfooded for a year. One thing I noticed while testing across agents is that some follow TDD a lot better than others, Codex struggled the most with the basic instructions.
Feedback welcome: