Docs
CommunityJev Cookbooks
Verifying LLM Answers Against Their Source
Official Jev cookbook that checks whether an LLM's answer follows from the paragraphs it was given, using three Noul questions in one request and a risk score that sends doubtful answers to review.
- Format
- Docs
- Reading time
- 3 min
- Published by
- Community
- Added
- Nov 2026
Highlights
- Asks three Noul questions per request: answerable, declines, and supported.
- Combines the three probabilities into one risk number; 0.2 or higher goes to review.
- Measured on 1,000 MuSiQue questions answered by gpt-6-luna, 473 of them answerable.
- The check passed 73% of answers and 95.7% of those were right.
- The 27% sent to review included 84 of the 115 wrong answers.
Questions about this entry
Short answers drawn from the linked project or page.
It checks whether an LLM's answer follows from the paragraphs it was given. One Jev request asks three Noul questions about the paragraphs and the answer: answerable (do the paragraphs state every fact the question needs), declines (does the answer say the paragraphs lack the answer), and supported (following the paragraphs step by step, do you arrive at the LLM's answer).
Install openai, ipython, matplotlib and cooksafe>=0.2.0,<0.3.0, then set TYPESAFE_API_KEY and OPENAI_API_KEY. The OpenAI key is used for the model whose answers are checked and, in the measurement, for settling answers that disagree with the dataset reference. A keyless client falls back to cache-only replay.
A few lines of code turn the three Noul probabilities into one risk number where higher means the answer is more likely wrong. If the LLM declined, risk is the chance the paragraphs do answer the question; if it answered, risk is the chance the paragraphs do not lead to its answer. A risk of 0.2 or more sends the answer to review.
Questions come from MuSiQue (Trivedi et al., CC BY 4.0), a fixed random sample of 1,000 development-set questions, each joining two to four Wikipedia questions with 20 paragraphs. Answers were written by gpt-6-luna, gpt-6.1-sol settled disagreements with the reference, and the check ran on jev-1.14.0 on 2026-11-07.
Of the 1,000 answers, 88.5% were right. The check passed 73% of answers and 95.7% of those passed answers were right. The remaining 27% went to review, and that review set contained 84 of the 115 wrong answers, so a share of wrong answers still passed the gate.
It takes a question, its paragraphs and an answer, and returns the three probabilities (answerable, declines, supported), the combined risk, and a pass or review verdict. The cookbook also uses cooksafe helpers such as JsonCache and make_playground_link for caching and inspecting runs.
It is built for answers grounded in retrieved paragraphs, so it does not apply to open-ended generation with no source text. It also needs both a TypeSafe key and an OpenAI key for the full run, and the published configuration used 4 Jev workers because more workers hit the public rate limit.
Reactions & coverage
Posts, threads, and videos about this entry from around the web.
X: Agent Handoff Gate: agents verify what they hand off
X: Jev as an LLM guardrail inside Agentgateway
X: Vercel's fx safety reviewer, measured at 18× faster
Reddit: Early experiments wiring Jev into Pi as a safety layer and model router.
From the Jev guides
Original write-ups on what this entry is for.
From the Jev AI model community
Posts from builders shipping with Jev right now.