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Promptfoo focuses on systematic testing and evaluation with assertions and red-teaming, while LangSmith focuses on tracing and observability. They're complementary — use Promptfoo for pre-deployment testing and LangSmith for production monitoring.
Yes. You can test whether agents call the right tools with correct parameters by asserting on function call outputs and tool selection patterns.
Yes. Promptfoo generates adversarial inputs that work against any LLM provider. It uses a separate model to generate attacks and evaluates target model responses.
Yes. Promptfoo provides a CLI that exits with appropriate status codes based on pass/fail thresholds, making it easy to integrate into any CI/CD pipeline.
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Last verified March 2026