Stay free if you only need core evaluation workflows and datasets and comparisons. Upgrade if you need unlimited access to platform features and enterprise deployment and data-control options subject to contract. Most solo builders can start free.
Why it matters: Self-serve subscription pricing is limited; teams still need to contact sales for enterprise contract pricing and deployment terms
Available from: API Usage
Why it matters: The platform is likely heavier than lightweight CI-only evaluation tools for small teams that only need prompt regression tests
Available from: API Usage
Why it matters: Advanced capabilities such as Percival and custom evaluator training may require higher-tier or enterprise access
Available from: API Usage
Patronus AI is best used for evaluating and governing production LLM, RAG, and agent systems. It is especially relevant when teams need hallucination detection, explainable LLM judges, red-teaming, guardrails, and observability in a single workflow. Based on our analysis of 870+ AI tools, Patronus is a stronger fit for enterprise AI safety and quality programs than for simple one-off prompt experiments.
The current tool data identifies Lynx as Patronus AI's hallucination-detection model. Lynx is designed to evaluate whether model outputs are supported by the provided context, which is particularly important for RAG systems. Accuracy will still depend on the quality of the source context, the evaluation dataset, and the thresholds a team configures for its use case.
Yes. Patronus supports custom evaluators for domain-specific checks, including natural-language criteria and code-based scoring functions according to the existing product data. This is useful for teams that need to evaluate legal compliance, medical safety language, brand voice, internal policy adherence, or other rules that generic evaluators will not understand reliably.
Yes. The current data states that Patronus provides CLI tools and API endpoints for running evaluations in CI/CD pipelines. Teams can configure pass/fail gates, such as blocking a deployment when hallucination rates exceed a defined threshold like 5% on a test set. This makes it useful for catching prompt, model, or retrieval regressions before they reach production users.
Patronus AI has a free Developer tier with up to 2 projects, 5 experiments per project, 2-week retention, unlimited comparisons and dataset access, and $10 in API credits. Paid API usage is listed at $10 per 1,000 small evaluator calls, $20 per 1,000 large evaluator calls, and $10 per 1,000 evaluation explanations. Enterprise pricing remains custom and requires contacting sales.
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Last verified March 2026