Overall ranking
Equal-weighted average across five comparable dimensions. Balance beats winning one column.
Full section →
Which AI eval platform actually catches failures without flagging good answers?
Scroll through each dimension. Five cards, one story.
Equal-weighted average across five comparable dimensions. Balance beats winning one column.
Full section →Top-left on the scatter wins. Catch failures with high recall without flagging good answers.
Full section →The scorer you enable can matter more than the vendor you choose.
Full section →Noveum returns a verdict in 0.59s, 2 to 27 times faster than the field.
Full section →Bright, even rows beat tall peaks and holes. Consistency is the rarest property in the study.
Full section →| faithF1 | ansRel | ctxRel | toolSel | |
|---|---|---|---|---|
| Noveum | 1.00 | 1.00 | 0.99 | 1.00 |
| DeepEval | 0.72 | 0.05 | 0.97 | 1.00 |
| Arize / Phoenix | 0.87 | 0.08 | 0.91 | 0.89 |
| Galileo | 0.92 | 0.00 | 0.83 | NA |
A real agent runs adversarial conversations. Each platform scores with its own native scorers, no cheat sheet. Five steps from stress test to published, reproducible scores.
LangGraph chatbot on gpt-4.1-mini over 599 documentation chunks. Grounded and deliberately ungrounded variants.
440 assistant turns · 131 genuine hallucinations · 9 adversarial scenario families
Claude Opus-4.8 labels every turn. Never shown to any platform.
Reference-free · each platform's documented best setup
Bootstrap 95% CIs, 2,000 resamples · fully re-derivable
Noveum's method beat ClosedQA on the identical GPT judge: 82% vs 55% recall. The difference is the method, not the model.
LangGraph RAG chatbot on gpt-4.1-mini. Skips retrieval on 53% of turns. 78% of its hallucinations came with no retrieved context at all.
Claude Opus-4.8 labels all 440 turns for hallucination, quality, relevance, and role adherence. Never an input to any platform.
Bootstrap 95% CIs on every rate. Paired significance tests on close calls. Ties reported as ties.
Who scores best across all dimensions on average? The composite is an equal-weighted average of the five dimensions that share a comparable metric. Balance beats winning one column.
Hosted-only scorers are excluded from a platform's average rather than counted against it.
Noveum 0.999 vs DeepEval 0.650. The composite gap at the top is decisive.
Only Noveum scores high across all five composite dimensions at once.
Ragas leads context-relevance. Braintrust leads faithfulness false-alarm rate. Arize has the best-balanced tool-argument profile. Noveum's headline is balance.
Faithfulness balances hallucination recall against false-alarm rate. For unsupervised gating, false alarms decide usability. Noveum leads on balance at 89% recall and 10% false-alarm; Ragas catches more but flags 37% of good answers.
Highest F1 and strongest quality correlation across faithfulness scorers.
Braintrust ClosedQA posts the lowest false-alarm rate in the study.
Ragas catches the most hallucinations but flags a third of good answers.
Patronus Lynx scores lowest on conversational fabrications it was built for.
The top three recall scores (Noveum, Braintrust, Arize) overlap within their confidence intervals. Under the stronger paired test, Noveum's edge over Braintrust is significant while its edge over Arize is borderline. We report the cluster as a statistical tie on purpose.
Full report
Go deeper with the 22-page report and buyer's guide — six job-to-shortlist maps built directly from the data.
The scorer you enable can swing results more than the vendor you pick. On identical turns, Braintrust swings 58 points between scorers; DeepEval's dedicated metric catches 1% vs 73% for GEval. Audit which scorer is actually enabled.
58-point swing on identical turns.
Dedicated metric: 1%. GEval: 73%.
High recall, nearly half of good answers flagged.
Same vendor, same data — opposite verdicts from scorer choice alone.
FaithfulnessMetric catches almost nothing; GEval catches 73% on identical turns.
Maxim catches nearly everything but flags almost half of good answers.
Aggregate recall hides specialization. Fabricated code APIs are hardest (21–88% recall); chained facts are solved at 100%. Prompt injection inverts rankings — chunk-level scorers lead, while Noveum peaks on out-of-scope fact pressure.
Invented SDK methods slip through most often. Noveum lands at 75%.
Every general-purpose judge hits 100% on chained-fact synthesis.
Noveum posts perfect recall on out-of-scope fact pressure.
Chunk-level scorers lead; Noveum's weakest substantial family at 55%.
RAG evaluation splits into context-relevance (retrieval quality) and answer-relevance (did the response address the question). Ragas leads context at r = 0.95; Noveum separates answer-relevance at r = 0.78 while peers cluster near zero.
Context relevance is the field's strongest dimension and it is not a Noveum win. Ragas leads at r = 0.95 with Noveum essentially tied at 0.945 (held-out validated at r = 0.93 on 280 turns its scorer never saw in development). Nearly half of all turns retrieved nothing, and the strong scorers all treat an empty retrieval as a true zero.
Answer relevance separated the field sharply. Noveum correlates at r = 0.78 while every other native scorer lands between 0.04 and 0.27. One caveat: this dimension had low variance in the gold labels, so it carries less statistical power than the others.
Agent failures are wrong tool choice or fabricated arguments in otherwise plausible calls. Only four platforms ship native tool-call scorers. Noveum and DeepEval tie on selection; Arize balances fabricated-argument detection best.
Noveum and DeepEval tie at perfect specificity on tool choice.
Arize posts the best balance; Noveum is the most cautious autonomous gate.
Gates want low false alarms; regression suites want exact-match recall.
Role-adherence asks whether the agent held persona across multi-turn pressure. Only Noveum and DeepEval ship native scorers. Noveum leads at r = 0.79; GPT-tier judges cluster at 0.56–0.68.
Noveum's native conversational scorer leads at r = 0.79 and separates good agents from bad ones most cleanly. The GPT-tier scorers cluster at r = 0.56 to 0.68. On this task, the judge model dominates the plumbing unless the scorer is genuinely specialized.
For realtime gates and high-volume scoring, a slow judge is a non-starter regardless of accuracy. Noveum 0.59s, 2 to 27 times faster than the field.
Latency here is the local judge-model call, measured identically for every platform, not a hosted-API round-trip. A 13 to 16 second judge (Ragas, Patronus) cannot sit in a request path.
Accuracy and speed together leave exactly one point on the frontier: Noveum is more accurate and faster than every other platform. Coverage is the multiplier everyone forgets. Scoring six dimensions costs six scorer-calls per turn, so a calibrated, cheap judge compounds.
A platform can win one dimension and still be a poor general-purpose evaluator if it is spiky. Normalized scores across five dimensions. Low spread means balanced performance.
NA means the platform ships a dedicated scorer that runs hosted or server-side (excluded, not zeroed). A 0.00 cell is the worst measured value or a confirmed capability gap. The five middle columns are each platform's normalized scores per dimension. The final σ column is the spread of those five scores, not a score itself. Noveum's σ of 0.002 means its five dimension scores are all near 1.0 with almost no gap between them. Low σ at a high mean is reliable everywhere, unlike flat-at-the-bottom Patronus. Noveum's overall score is 0.999, never 0.002.
| Faith F1 | Ans-rel | Ctx-rel | Tool-sel | Role-adh | σ | |
|---|---|---|---|---|---|---|
| Noveum | 1.00 | 1.00 | 0.99 | 1.00 | 1.00 | 0.002 |
| DeepEval | 0.72 | 0.05 | 0.97 | 1.00 | 0.52 | 0.348 |
| Arize / Phoenix | 0.87 | 0.08 | 0.91 | 0.89 | 0.13 | 0.385 |
| Galileo | 0.92 | 0.00 | 0.83 | NA | 0.48 | 0.362 |
| Ragas | 0.49 | 0.35 | 1.00 | 0.13 | 0.48 | 0.287 |
| Maxim | 0.89 | 0.05 | 0.00 | NA | 0.44 | 0.358 |
| Braintrust | 0.90 | 0.31 | 0.16 | 0.00 | 0.00 | 0.333 |
| Patronus | 0.00 | 0.00 | 0.00 | 0.00 | 0.39 | 0.157 |
The headline number. Use this for any bar or chart.
Consistency only. Lower is better. Never use as the score.
Noveum is the only platform both high and flat across every measured dimension, with a mean of 0.999 and a spread of just 0.002. Every other competitive platform carries at least one tall peak and one hole: DeepEval's near-zero answer relevance, Braintrust's missing tool and conversational scorers, Galileo's and Maxim's faithfulness over-flagging. If one platform must cover a whole agent, consistency is the number to check.
Reproducible · Open data
22-page benchmark plus buyer's guide. Every score reproducible.