RAG evaluation services

Human reviewers judge both halves of your retrieval-augmented generation system: whether the retrieved passages are relevant, and whether every claim in the answer is supported by them. In the languages your users ask questions in.

User questionWhat is the refund window for annual plans?
1Refund policy: annual plans can be refunded within 30 days of purchase.Relevant
2Pricing page: monthly and annual plan prices.Partly
3Blog: five tips for working from home.Not relevant
Model answerAnnual plans can be refunded within 30 days of purchase.[1] Refunds reach your account within 24 hours.
Claim 1 supported by [1]Claim 2 not in any sourceRetrieval: 1 of 3 relevant
Retrieval
Passage relevance and ranking for each question
Answers
Claim-by-claim grounding, completeness and citations
Questions
Realistic test questions written by native speakers
Output
Labeled test sets, scores per language and a failure report

What RAG evaluation is

RAG evaluation is measuring how well a retrieval-augmented generation system finds the right information and uses it. A RAG system can fail at retrieval, by fetching the wrong passages, or at generation, by adding claims the passages don't support. Good evaluation separates the two, so you know which part to fix.

Human labels give you a trusted reference for both. They're also the data you need to check whether an automated LLM judge agrees with people before you rely on it.

What we evaluate

Against your documents, your questions and your definition of a good answer.

  • Retrieval relevance

    Each retrieved passage rated for how well it answers the question, so you can measure precision and ranking.

  • Answer grounding

    Every claim in the answer checked against the passages: supported, unsupported or contradicted.

  • Completeness

    Whether the answer covers what the user needed, or misses information the sources had.

  • Citations

    Whether each citation points to a passage that actually supports the sentence.

  • Cross-language retrieval

    Questions in one language answered from documents in another, checked by bilingual reviewers.

  • Test set writing

    Realistic questions with reference answers and source passages, written from your documents.

How a RAG evaluation runs

Reviewers read your source documents as well as the answers.

  1. Scope

    Your document set, sample questions, languages and scoring rubric.

  2. Test set

    We write or collect questions and, if needed, reference answers.

  3. Calibration

    Reviewers score a shared sample and agree on what counts as supported.

    Agreement check QA
  4. Review

    Retrieval and answers labeled for each system version you send.

  5. Report

    Scores per language and question type, with examples of each failure.

Questions about RAG evaluation

What is RAG evaluation?

RAG evaluation measures how well a retrieval-augmented generation system works. It checks whether the system retrieves relevant passages for a question, and whether its answer is supported by those passages, complete and correctly cited.

Why use human reviewers instead of an LLM judge?

An LLM judge is fast, but you need to know it agrees with people first. Human labels give you that reference, and they catch subtle failures such as an answer that sounds right but adds a detail no source contains.

Can you evaluate RAG systems in other languages?

Yes. Native-speaker reviewers judge questions and answers in each language, including cross-language cases where the question and the documents are in different languages.

What do you need from us?

Access to the source documents or passages, a set of questions or logs, the system's retrieved passages and answers, and your rubric. We can write the rubric and test questions with you.

Evaluate your RAG system

Send sample questions, retrieved passages and answers, or book a call. We calibrate reviewers and score a pilot set.

Phone hours
Weekdays 9:30 to 16:00, weekends 9:30 to 12:00, UK time

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30 minutes with our project team. Choose a weekday and a time between 10:00 and 18:00 UK time.

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