arXiv Computation and Language

Beyond Accuracy: How Quantization Affects Coding Agents

The paper investigates how quantization affects coding agents that generate and revise programs. It compares BF16, 4‑bit AWQ, and GPTQ quantization methods on Qwen2.5‑Coder‑Instruct and Devstral‑Small‑2507 models across various sizes and seeds, finding no significant loss in final accuracy. However, quantization changes behavior: it alters one‑shot versus loop‑based solve rates, tool‑use patterns, and failure modes such as compilation errors and runtime issues.

arXiv AI
Oct 7

Quantization Effects on Tool-Failure Recovery Vary Across Prompts and Evaluation Designs

The study investigates how post‑training quantization (8‑bit vs. 4‑bit) affects language‑model agents’ ability to recover from temporary tool failures. Using Llama‑3.1‑8B‑Instruct and Qwen2.5‑7B‑Instruct on twenty deterministic tool‑use tasks across five prompts, the authors find that recovery performance varies with prompt, evaluation target, and scoring policy, sometimes favoring 8‑bit, sometimes 4‑bit, and even reversing direction under different conditions. The results highlight that a single prompt, task set, or scoring rule cannot reliably determine the robustness of quantized agents. whyItMatters":"The findings emphasize that evaluation design choices critically influence conclusions about quantized‑agent robustness, underscoring the need for comprehensive, matched‑task assessments before deployment decisions are made."

By Yuhe Hu
arXiv AI
Oct 9

Code Understanding is a Bottleneck for Coding Agents

The paper introduces CABRA, a synthetic benchmark that constructs coding tasks from scratch using call‑graph transformations and scales difficulty along four axes: function traversal, search, runtime resolution, and instruction following. Experiments with eight large language models and six coding agents on 6,840 CABRA tasks show that while LLM accuracy degrades with task size, agents maintain high performance by leveraging tools; larger tasks trigger more tool calls, and a separate study on SWE‑bench verifies that tool‑call counts better predict agent accuracy than lines of code edited. The authors argue that CABRA exposes weaknesses in LLMs that are hidden by tool use and highlights the importance of code‑understanding abilities beyond mere editing. whyItMatters":"The study demonstrates that coding agents’ performance is more dependent on code‑understanding than on the amount of code edited, revealing a critical bottleneck for current coding agents."

By Nishant Balepur, Kiran Tomlinson, Tobias Schnabel
arXiv Computation and Language
Oct 1

QuantCode Model: Specializing Language Models for Executable Algorithmic Trading Code

The paper introduces the QuantCode Model, a specialized language model for generating executable algorithmic trading code. It combines continued pretraining on trading framework code with supervised fine‑tuning on validated request‑to‑code pairs, achieving significant gains on the QuantCode‑Bench benchmark and improving both single‑turn and multi‑turn agentic success rates. The study also highlights the importance of retaining parsing and tool‑calling capabilities during domain specialization.

By Alexey Chernysh, Orkhan Ekhtibarov, Dmitry Zmitrovich
arXiv AI
Jul 22

Don't Blame the Large Language Model: How Agent Harness Evolution Shapes Coding Agent Quality

arXiv:2607. 03691v2 Announce Type: replace-cross Abstract: Coding agents, autonomous systems that use large language models (LLMs) to resolve software engineering tasks, rely on agent harness: a middleware layer in between a developer and a large language model that orchestrates system prompts, tool execution, context management, and iterative reasoning loops.

By Oussama Ben Sghaier, Hao Li, Bram Adams, Ahmed E. Hassan
arXiv AI
Aug 20

A Jagged Frontier: Evaluating Robustness of Code Agents to Semantics-Preserving Transformations

The paper investigates how AI code agents perform when the surrounding code is rewritten in a semantically equivalent way. Using a random variant sampler that applies control‑flow rewrites, dead‑code injection, and identifier renaming, the authors evaluate two agent scaffolds—mini‑SWE agent and OpenCode—backed by four frontier models across SWE‑bench datasets. Results show modest drops in resolve‑rate (up to 6.7 percentage points) with significant degradations in 6 of 16 configurations, and reveal that robustness varies across models and scaffolds, forming a jagged frontier.

By Hasan Najib Mahmud (Colorado State University), Shreya Gupta (Microsoft), Isha Chaudhary (University of Illinois Urbana-Champaign), Nathaniel Enis (Colorado State University), Ravi Mangal (Colorado State University), Gagandeep Singh (University of Illinois Urbana-Champaign), Corina Pasareanu (Carnegie Mellon University)