Honest pros, cons, and verdict on this testing & quality tool
✅ Comprehensive red-teaming fills a critical gap in LLM safety tooling
Starting Price
Free
Free Tier
Yes
Category
Testing & Quality
Skill Level
Developer
Open-source LLM testing and evaluation framework for systematically testing prompts, models, and AI agent behaviors with automated red-teaming.
Promptfoo is an open-source testing and evaluation framework designed to help developers systematically test LLM applications, prompts, and AI agent behaviors. It provides a CLI-driven workflow for defining test cases, running evaluations across multiple models and prompt variants, and comparing results with automated scoring — essential for building reliable AI agents that behave predictably in production.
The framework supports a wide range of assertion types including exact matching, semantic similarity, model-graded evaluations, and custom JavaScript/Python assertions. Developers can test across multiple LLM providers simultaneously, comparing how different models handle the same prompts and scenarios. This is particularly valuable for agent development where choosing the right model for each task is critical.
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Learn more →Promptfoo delivers on its promises as a testing & quality tool. While it has some limitations, the benefits outweigh the drawbacks for most users in its target market.
Open-source LLM testing and evaluation framework for systematically testing prompts, models, and AI agent behaviors with automated red-teaming.
Yes, Promptfoo is good for testing & quality work. Users particularly appreciate comprehensive red-teaming fills a critical gap in llm safety tooling. However, keep in mind openai acquisition may affect future open-source direction.
Yes, Promptfoo offers a free tier. However, premium features unlock additional functionality for professional users.
Promptfoo is best for Security teams needing to red-team LLM applications before deployment and Development teams comparing prompt performance across multiple models. It's particularly useful for testing & quality professionals who need advanced features.
Popular Promptfoo alternatives include Braintrust, LangSmith, Humanloop. Each has different strengths, so compare features and pricing to find the best fit.
Last verified March 2026