arXiv AI

Constraint Decay: The Fragility of LLM Agents in Backend Code Generation

arXiv AI
Oct 28

Benchmarking LLM Agents for Behaviorally Adequate Test Generation from Software Requirements

The paper introduces Req2Test-Bench, a benchmark of 5,086 instances linking natural‑language Gherkin requirements to developer‑written test implementations across five languages and four BDD frameworks. It evaluates eight agent–model–reasoning setups, finding that while the best configuration (Codex with DeepSeek‑V4.1‑Flash) produces passing tests for 82.8% of cases, only 33.8% are behaviorally adequate, as measured by kill‑completeness. The study highlights diminishing returns from scaling agents, the impact of under‑specified requirements, and the potential of requirement‑grounded harnesses to improve test generation.

By Binhang Qi, Yiming Liu, Yun Lin, Yangjie Zhou, Hailong Sun, Jin Song Dong
arXiv AI
Oct 1

E2E-SWE: Benchmarking LLMs on Building Working Codebases from Scratch

E2E-SWE is a benchmark that tests large language models’ ability to create complete, functional software repositories from scratch. It includes 186 tasks across 11 programming languages, each requiring an agent to build an installable project based solely on a natural‑language specification and an empty workspace, while passing a hidden test suite. The benchmark was crafted by software engineers and LLMs, then refined through iterative verification by autonomous agents to ensure clarity and solvability.

By Hantian Ding, Chloe Bi, Jiacheng Zhu, John Yang, Matt Deitke, Pengcheng Yin, Zijian Wang, Rui Hou
arXiv AI
Oct 2

Code That Works, Environments That Don't: Measuring Environment Reproducibility in AI-Generated Software

The paper investigates how well large language models specify the software environments needed to run AI-generated code. Using a new agent protocol and a three‑layer dependency framework, the authors evaluate three coding agents across four languages and fifty tasks, finding that dependency specifications are often inconsistent, redundant, or incomplete. Agreement on dependency sets is as low as 7% for identical tasks, and newer agents show no improvement, indicating that environment specification remains a significant, unaddressed challenge in code generation.

By Bhanu Prakash Vangala, Tanu Malik
Hugging Face Trending Papers
Jul 13

BackendForge: Benchmarking Agentic End-to-End Code Generation with Backend Services

Large language models (LLMs) are increasingly used in agentic coding settings, where they can inspect files, execute commands, run tests, observe failures, and iteratively revise code. This shift raises a central evaluation question: can an agentic LLM generate an end-to-end software artifact that is both deployable and behaviorally correct under execution?

arXiv AI
Oct 12

AgentSWE: Can Coding Agents Build the Agent You Actually Want?

AgentSWE is a new benchmark for agent software engineering that evaluates coding agents across three lifecycle stages: creating an agent from a natural‑language requirement, editing existing agent codebases, and optimizing toward a measurable target. The benchmark consists of 25 commission‑style tasks, where builders iterate on a few illustrative cases and are then tested on held‑out cases that cover the full requirement, with hard pass/fail gates or objective‑based grading. Experiments show that current coding agents fail to meet the requirements, revealing common failure modes such as overfitting, incomplete runtimes, and unsupported completion claims.

By Jiahao Wang, Hongjin Qian, Yuyang Hu, Jiajun Zhang, Zheng Liu
arXiv AI
Oct 31

Skeleton Coding: Program Structure as a Specification for Agents

The paper introduces Skeleton Coding, a method where developers jointly specify a program’s structure—its data types, modules, and functions—alongside behavioral tests. This approach allows the agent to first commit to a structure, narrowing the search space of possible programs, and then use tests to select the correct implementation. Empirical results across multiple models and benchmarks show that skeletons can dramatically reduce the number of required tests, improve accuracy, and lower implementation costs.

By Aditya Golatkar, Alessandro Achille, Renos Zabounidis, Vlad Sobal, Yangruibo Ding, Baishakhi Ray, Jonathan Buck, Guy Van den Broeck, Maryam Fazel, Pietro Perona, Wei Xia, Stefano Soatto
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