Large language models (LLMs) are largely motivated by their performance on popular topics and benchmarks at the time of their release. However, over time, contamination occurs due to significant exposure of benchmark data during training. This poses a risk of model performance inflation if testing is not carefully executed. To address this challenge, we present GRAFITE, a continuous LLM evaluation platform through a comprehensive system for maintaining and evaluating model issues. Our approach enables building a repository of model problems based on user feedback over time and offers a pipeline for assessing LLMs against these issues through quality assurance (QA) tests using LLM-as-a-judge. The platform enables side-by-side comparison of multiple models, facilitating regression detection across different releases. The platform is available at https://github.com/IBM/grafite. The demo video is available at www.youtube.com/watch?v=XFZyoleN56k.
Figures & tables
Figure 1: The pipeline of Grafite and stakeholders of each step
Issue Title : Math - Geometry
User input : A triangle has a base of 6.5 meters and a height of 4.3 meters. Calculate its area.
Model Output : <to be generated by the selected model> .
Sample Reference Answer (ground truth) :
To calculate the area of a triangle, you can use the formula Area=21×base×height . Since the given base is 6.5 meters and the given height is 4.3 meters, the area of the triangle is 21×6.5×4.3 . Thus, Area=21×6.5×4.3=3.25×4.3=13.975 square meters. Therefore, the area of the triangle with a base of 6.5 meters and a height of 4.3 meters is 13.975 square meters.
Evaluation Criteria
Judge Type : "Prompt template 1: input + output + ground truth + judge guideline"
Table 1: A sample test from an issue.
Figure 2: Illustration of Grafite ’s evaluation components. Screenshots are drawn from the use case test run results, described in Section 4
Geometry, Riddle With Manipulation, Simplify Algebraic Equations, Word Pattern
4
20
Multilingual
No Translation Needed, Translation
2
10
Table 2: Issue distribution aggregated by domain. Ni : number of issues. Nt : number of tests.
Issue Domain
L3.1
L3.2
L3.3
LMav
( n tests)
8B
3B
70B
17B
Total (110)
42.1
26.3
57.9
63.2
Code (17)
76.5
64.7
76.5
100
Creative (6)
100
83.3
100
83.3
Factual (17)
5.9
5.9
17.7
29.4
Instr. follow (12)
41.7
25
25
58.3
Table 3: Llama Models Pass rate (%) per issue.
Platform Feature/User Experience Dimension
μ
σ
Value of human-in-the-loop annotation for improving evaluation quality
4.13
0.64
Usefulness of ensemble evaluation approach (multiple LLM judges)
4.13
0.84
Usefulness of pass/fail metrics for evaluating model performance
4.13
0.84
Effectiveness in tracking regression tests across issues
4.13
0.84
Confidence in LLM-as-a-judge evaluation accuracy
4.00
0.53
Ease of creating test runs
4.00
0.76
Table 4: User Experience Statistics for Grafite : Dimensions ranked by average satisfaction and effectiveness ratings. Higher μ values indicate greater user satisfaction, while lower σ values indicate more consistent agreement among participants.
Reliable evaluation of tool routing is critical as Large Language Models increasingly operate as autonomous agents. Current benchmarks face three structural limitations: data distributions that follow a power law leave rare scenarios underrepresented; the absence of adversarial hard negatives obscures performance differences across models; and annotation pipelines depend on LLM judgments that have not been validated through execution. In this paper, we introduce PluginEval, a benchmark constructed through a two-stage framework that systematically mitigates these limitations. First, we formulate tool routing as a sequence of three decisions and separate generation from verification. LLMs propose candidate calls, while deterministic validation and real API execution provide reliable quality signals. Second, we decompose each plugin by capability, intent, and boundary to identify trigger and exclusion scenarios. We then generate queries at different difficulty levels to fill coverage gaps, including adversarial negatives targeting three failure modes, and return them to the first stage for annotation. This process creates a closed loop that iterates until coverage converges. For evaluation, we move beyond aggregate accuracy. An LLM judge anchored to gold annotations classifies failures as missed calls, spurious calls, or parameter errors, producing a detailed error profile for each model. We evaluate five model families, including proprietary models and models with open weights, analyze their performance across difficulty levels and error categories, and validate the judge through agreement with human annotations.
Dongjie Xu, Julius, Hanchi Dong +6
Soochow University · Tencent Inc. · Beijing University of Posts and Telecommunications +4
Large Language Models (LLMs) increasingly serve as reasoning components in modern software systems, yet a model that answers a logical query correctly can contradict itself when the same problem is restated in an equivalent form. Static benchmarks evaluate queries in isolation and therefore fail to expose such inconsistencies. To address this limitation, we present LGMT, an open-source tool that detects reasoning inconsistencies through metamorphic relations grounded in first-order logic. Given a source test case in premise-conclusion form, LGMT generates logically equivalent follow-up cases and checks whether the model's entailment predictions agree across the pair, without ground-truth labels. The tool provides 20 built-in metamorphic relations, supports custom ones verified by the Z3 theorem prover, and runs from a CLI or a web studio, including an offline mock mode requiring no API key. Across six widely used LLMs on a bundled benchmark of 3,091 metamorphic groups, LGMT reveals inconsistency rates ranging from 20.84% to 29.44%. LGMT is publicly available on GitHub at https://github.com/MaxwelsDonc/lgmt-tool, with a demonstration video at https://youtu.be/gou4opptu1U.
Zenghui Zhou, Xiaoke Fang, Zheng Zheng
School of Automation Science and Electrical Engineering, Beihang University Xueyuan Road, Haidian District, Beijing, 100191, China
Continuous evaluation of LLM products relies on a strong LLM judge treated as ground truth: a cheap monitor scores every interaction and a team is paged when the score drifts down. But the judge is itself a model behind an API, and a silent version bump or scoring-prompt update changes how it scores -- so every drift alarm is ambiguous between a worse product and a changed judge. We resolve the ambiguity with a fixed, human-labeled anchor set that the current judge re-scores at a steady interleave, a second betting e-process on the judge-versus-human gap, and a guard-window rule returning a verdict in {none, system, judge}. We prove anytime-validity, one-way identification (only the judge can move the anchors), an attribution race whose design law is that the anchors must out-run the main process they guard, and process orthogonality. On two real judge changes, a silent version bump is detected as judge drift in 60/60 runs with zero judge-to-system misattribution, and a contaminating strict-prompt change is correctly attributed on 110 of 120 runs at guard width 300 -- while the industry-default rolling z-test false-alarms on 75% of drift-free streams. Every experiment replicates on a second domain (TL;DR summarization) with nothing re-tuned, and where the domains differ the differences are the ones the race predicts: the strict-prompt change shifts scores harder there, so the anchors fire faster and attribution becomes perfect (240/240). The monitor runs at approximately 0.64 of the cost of strong-judging every item, or 0.21 in a cheaper-but-deafer regime.