Promptfoo

Promptfoo is an open-source command-line tool and library for testing applications built on large language models. Developers describe test cases and checks in declarative configuration files, run them against one or more models, and review the results, which replaces manual trial and error with repeatable evaluations. It is written in TypeScript and released under the MIT license.

Beyond quality testing, Promptfoo includes red teaming and vulnerability scanning for AI systems, probing prompts, agents, and retrieval-augmented generation (RAG) pipelines for security and safety weaknesses. It can compare models from providers such as OpenAI, Anthropic, Azure, Bedrock, and Ollama side by side, and it works with any LLM API or programming language. Its documentation also covers a code-scanning feature that reviews pull requests for LLM-related security and compliance issues.

The project is designed to run locally: the maintainers state that evaluations execute on the developer's own machine, so prompts only leave it when a chosen model provider receives them. It can be installed with Homebrew or pip, or run without installing via npx, and it plugs into CI/CD so checks run automatically on each change. The README notes that Promptfoo is now part of OpenAI while remaining open source and MIT licensed.