Vision-language models (VLMs) are increasingly adopted as judges for subjective assessment, yet absolute scoring remains brittle due to inconsistent scales and inherent preference biases. To bridge this gap, we propose S²AD (**Semantic-Anchored Scale-Agnostic Distillation**), a novel easy-to-hard framework that operationalizes subjective assessment as comparative analysis, conceptualizing the judge’s evolution from mimesis to metamorphosis. In Stage 1 (Mimesis), we introduce Dynamic Soft Positioning (DSP) to train the judge to compare a query against retrieved reference images, establishing a relative evaluation space that ensures consistent ordering under heterogeneous scales. In Stage 2 (Metamorphosis), this comparative capability is internalized via Language Buttons—discrete semantic levels serving as a retrieval-free internal reference. Optimized with Group Relative Policy Optimization (GRPO), S²AD achieves efficient, scale-steerable inference that adapts to diverse grading standards. Our framework reaches state-of-the-art performance across multiple benchmarks, validating the effectiveness of internalized comparative priors for robust, rank-invariant, and scale-steerable evaluation. The code is available at: https://github.com/SpatialVision-Research/SSAD_ACL2026_Findings.

LLM-based agents can greatly extend the abilities of LLMs and thus attract sharply increased studies. An ambitious vision – serving users by manipulating massive API-based tools – has been proposed and explored. However, we find a widely accepted evaluation mechanism for generic agents is still missing. This work aims to fill this gap. We decompose tool use capability into seven aspects and form a thorough evaluation schema. In addition, we design and release an instruction dataset and a toolset – the two sides that the agents bridge between – following the principle of reflecting real-world challenges. Furthermore, we evaluate multiple generic agents. Our findings can inspire future research in improving LLM-based agents and rethink the philosophy of API design.

Open-domain question answering (OpenQA) aims to answer questions based on a number of unlabeled paragraphs. Existing approaches always follow the distantly supervised setup where some of the paragraphs are wrong-labeled (noisy), and mainly utilize the paragraph-question relevance to denoise. However, the paragraph-paragraph relevance, which may aggregate the evidence among relevant paragraphs, can also be utilized to discover more useful paragraphs. Moreover, current approaches mainly focus on the positive paragraphs which are known to contain the answer during training. This will affect the generalization ability of the model and make it be disturbed by the similar but irrelevant (distracting) paragraphs during testing. In this paper, we first introduce a ranking model leveraging the paragraph-question and the paragraph-paragraph relevance to compute a confidence score for each paragraph. Furthermore, based on the scores, we design a modified weighted sampling strategy for training to mitigate the influence of the noisy and distracting paragraphs. Experiments on three public datasets (Quasar-T, SearchQA and TriviaQA) show that our model advances the state of the art.