Promptfoo

What is Promptfoo?

Promptfoo is a open source (mit) ai prompt generator developed by Promptfoo Open Source Team. It is an open-source evaluation framework that lets developers systematically test LLM prompts, model variations, and RAG outputs against test cases to measure accuracy, latency, and hallucination rates.

Core Technical Capabilities

• Automated Prompt Matrix Testing: Runs multiple prompt variations against datasets to compare output consistency across OpenAI, Anthropic, and local models.
• Red-Teaming & Jailbreak Detection: Includes automated test suites for prompt injections, jailbreaks, PII leakage, and toxic responses.
• CI/CD Pipeline Integration: Executes prompt assertions as GitHub Actions or pre-commit hooks to catch regressions before deployment.

Practical Workflows & Use Cases

• Prompt Regression Testing: Verifies that tuning a system prompt for one edge case does not break existing application behavior.
• Model Comparison Benchmarks: Evaluates whether switching from GPT-4o to Claude 3.7 Sonnet improves domain-specific accuracy.
• Security Compliance Audits: Probes enterprise customer-facing assistants for system prompt extraction vulnerabilities.

Promptfoo vs Alternatives

When selecting tools in the ai prompt generator ecosystem, developers frequently compare Promptfoo against alternative solutions:

• DeepEval: DeepEval is a unit testing framework for Python, while Promptfoo operates as a fast CLI tool configured with simple YAML files.
• Manual Playground Testing: Manual copy-pasting into playgrounds lacks statistical rigor, whereas Promptfoo runs parameterized batch assertions.

Technical Specifications

Frequently Asked Questions