Promptfoo – CLI for testing & improving LLM prompt quality

In plain words

Promptfoo is a command-line tool for testing and evaluating large language model prompts. It helps developers and teams systematically assess prompt quality through automated testing. The tool is designed for anyone working with LLMs who needs to measure and iterate on prompt performance. It launched as an open-source project on GitHub, making it accessible for developers looking to improve their LLM applications through structured evaluation and comparison.

written from the facts on this page · September 2026

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