arXiv AI

MC-EvoBench: Auditing Experience-Driven Self-Improvement in Minecraft Agents

MC‑EvoBench is a controlled Minecraft benchmark designed to audit experience‑driven self‑improvement in agents. It features 19 evolution chains (12 primary, 7 calibration/probe) and three graph‑aligned probe families, each task represented as a task‑state graph with stage‑level verifiers and strict source‑target boundaries. The benchmark evaluates probes under no‑prior, related, unrelated, and shuffled source conditions, reporting metrics such as TSR, WGP, and VMP while preserving provenance records.

arXiv Computation and Language
Sep 7

EVOHARNESSBENCH: Can Your Agents Keep Pace with an Evolving Harness?

EVOHARNESSBENCH is a new benchmark that tests how LLM-based agents handle changes in their tool, skill, and agent harnesses over time. It includes 17 deterministic harness streams with 802 tasks, 520 tools, 42 skills, and 62 agents, and evaluates agents in two settings: deployment evaluation and self‑evolving adaptation evaluation. The study finds that harness expansion can cause forgetting, adaptation gains are inconsistent, and preserving old competence does not always aid new capability adaptation, highlighting harness evolution as a distinct challenge for agent development.

By Zixuan Ke, Vaidehi Patil, Haizhou Shi, Yang Li, Ye Liu, Sarath Shekkizhar, Anurag Koul, Jiayu Wang, Xuan Phi Nguyen, Semih Yavuz, Mohit Bansal, Shafiq Joty
arXiv Computation and Language
Sep 14

EvoHarnessBench: Can Your Agents Keep Pace with an Evolving Harness?

arXiv:2609.04280v2 Announce Type: replace-cross Abstract: Modern LLM-based agents operate through a harness of tools, reusable skills, and specialist agents that shapes what they observe and what the...

By Zixuan Ke, Vaidehi Patil, Haizhou Shi, Yang Li, Ye Liu, Sarath Shekkizhar, Anurag Koul, Jiayu Wang, Xuan Phi Nguyen, Semih Yavuz, Mohit Bansal, Shafiq Joty
arXiv Computation and Language
Aug 28

MineExplorer: Evaluating Open-World Exploration of MLLM Agents in Minecraft

MineExplorer is a benchmark designed to assess the open‑world exploration abilities of multimodal large language models (MLLMs) in Minecraft. It filters out tasks that rely heavily on Minecraft‑specific knowledge, organizes tasks into ReAct‑style capabilities, and composes atomic tasks into implicit multi‑hop challenges. A multi‑agent synthesis workflow creates reliable task graphs, sandbox scenes, and rule‑based milestone evaluators, and human evaluation confirms its superiority over a single‑agent baseline. Experiments show that while advanced MLLMs can handle many single‑hop tasks, they struggle with longer trajectories that require coordinating hidden prerequisites, and larger models or different thinking modes do not consistently improve performance.

By Tianjie Ju, Yueqing Sun, Zheng Wu, Wei Zhang, Yaqi Huo, Xi Su, Qi Gu, Xunliang Cai, Gongshen Liu, Zhuosheng Zhang
arXiv AI
Sep 12

Grounding Agent Memory: Environment-Probing Curation for Enterprise Agents

The paper introduces environment‑probing curation, a deployment‑compatible method that equips asynchronous curator agents with read‑only world tools to verify, scope, and refresh candidate memories without retraining models. In a GitHub Copilot‑based harness, this approach improves pass rates on CLBench from 39% to 73%, boosts reward metrics, and reduces both query counts and task‑agent costs. Across six APEX management‑consulting tasks, the method consistently outperforms baselines, yielding higher rewards and fewer tool calls while maintaining a compact task‑time interface.

By Susheel Suresh, Hazel Mak, Sahil Bhatnagar, Chhaya Methani, Alejandro Gutierrez Munoz
arXiv AI
Oct 28

The Trinity:Capability-Driven Recursive Self-Improvement for Multimodal Agents

The paper introduces The Trinity, a recursive self‑improvement framework for multimodal agents that couples world generation with harness evolution through three roles: Creator, Explorer, and Evolver. By shifting task organization from surface categories to shared capability requirements, it builds a hierarchical capability tree and a reusable harness tree, enabling efficient transfer learning across heterogeneous tasks. Experiments show the evolved harnesses improve mean performance by 34 points on 28 training benchmarks and 26 points on 18 unseen benchmarks, including two real‑world embodied tasks.

By Weidong Tang, Ruiheng Wang, Jingxuan Zhang, Hexin Wang, Haoyuan Chen, Zhengfeiyang Zhang, Yixing Ma, Zichen Jiang, Ziyu Guo, Haodong Li, Zhengbo Jiao, Zhiqing Cui, Xinxiang Yin, Shuo Liang, Zhenglin Wan, Hongzhan Lin, Wangbo Zhao Kaipeng Zhang, Pengfei Zhou, Odin Zhang, Yang You
arXiv AI
Oct 2

Mingbird: A Local-First Agent Harness Enabling Small Open Models to Complete Real Tasks

Mingbird is a local‑first agent harness designed for small open‑weight language models (2–9 B) that run on ordinary laptops. It introduces ten mechanisms—such as a byte‑level net‑zero prefill budget, a finish gate that re‑reads the task before accepting completion, and signature‑level loop detection—to address common failure modes that arise from the harness rather than the model itself. In controlled experiments on the LRAB benchmark and the $ au^2$‑bench, Mingbird achieves higher overall scores (0.886 and 0.856 respectively) compared to other harnesses, and its ablation studies show that each mechanism contributes measurable performance gains.

By Hao Wang, Ting Huang
arXiv AI
Oct 15

Long-Horizon-Terminal-Bench 2.0: Automating Diverse Task Construction and Measuring Sustained Agent Progress

arXiv:2610.14146v1 Announce Type: new Abstract: Long-horizon terminal benchmarks measure whether an agent can sustain progress through extended workflows with process rewards, not only whether its fi...

By Zongxia Li, Zhongzhi Li, Yucheng Shi, Ruhan Wang, Junyao Yang, Chengsong Huang, Zhichao Liu, Xiyang Wu, Anhao Li, Yue Yu, Ergan Shang, Fuxiao Liu, Tong Zheng, Ninghao Liu, Lichao Sun, Haitao Mi, Leowei Liang
arXiv Computation and Language
Oct 22

VeriEvolve: Evaluator-First Evolution for Tool-Using Agents

VeriEvolve is an evaluator-first evolution framework that first builds an executable evaluator from task instructions, then uses this evaluator as a frozen fitness signal while evolving agents. The system generates challenge states and counterfactual test cases to refine the evaluator across rounds, producing 30 evaluators for 30 MCPMark Filesystem tasks with perfect agreement on generated suites and high agreement on held-out states. Evaluator-guided evolution significantly improves externally verified success rates for GLM-5.2 and Claude, and cross-environment studies reveal complementary limits from observability, state representation, and search/execution capacity.

By Yueshen Li, Kamer Ali Yuksel, Gokhan Tur, Dilek Hakkani-T\"ur, Jo\~ao Pedro Maia