Promptfoo

Promptfoo lets you test prompts the way you would test code. You write a config with example inputs and expected qualities, run it across different models, and get a table showing which prompt performs best. It also includes red-teaming tools that probe your app for jailbreaks, data leaks and other risky behavior. It runs locally or in CI, so tests can block a bad change before release. Promptfoo is open source and free to use, with an enterprise offering for larger teams. It suits developers who want repeatable evaluations instead of guesswork.