Harness-of-Harness: Multi-Day Autonomous Software Development with Continual Improvement

arXiv:2609.01481 · cs.AI · Submitted 2026-09-01 · Read on arXiv

cs.AI

Submitted: 2026-09-01

Updated: 2026-09-01

Code: https://github.com/openai/codex

Terminology

• Benchmark — 75× in this paper · explained in 2 episodes
• Core — 14× in this paper · explained in 2 episodes
• Ablation — 13× in this paper · explained in 1 episode
• Trace — 13× in this paper · explained in 2 episodes
• Verification — 7× in this paper · explained in 2 episodes
• Ablation study — 5× in this paper · explained in 1 episode
• Benchmarking — 4× in this paper · explained in 3 episodes
• Human-in-the-Loop — 3× in this paper · explained in 3 episodes
• Quality Assurance — 3× in this paper
• Agent Harness — 2× in this paper · explained in 2 episodes
• Aggregation — 2× in this paper · explained in 1 episode
• Reinforcement Learning — 2× in this paper · explained in 4 episodes
• State Management — 2× in this paper · explained in 3 episodes
• Verifier — 2× in this paper · explained in 2 episodes
• AI Agents — 1× in this paper · explained in 2 episodes
• AI Foundation Model — 1× in this paper · explained in 1 episode
• Abstraction — 1× in this paper · explained in 1 episode
• Agentic Coding — 1× in this paper · explained in 1 episode
• Agentic System — 1× in this paper · explained in 2 episodes
• Alignment — 1× in this paper · explained in 1 episode
• Consistency — 1× in this paper · explained in 3 episodes
• Foundation Model — 1× in this paper · explained in 3 episodes
• Foundation Models — 1× in this paper · explained in 7 episodes
• Harness of Harness — 1× in this paper
• Iterative Refinement — 1× in this paper · explained in 3 episodes
• Large Language Models (LLMs) — 1× in this paper · explained in 6 episodes
• Multi-Agent Framework — 1× in this paper · explained in 3 episodes
• Multi-agent Collaboration — 1× in this paper · explained in 2 episodes
• Multi-agent Collaborative Framework — 1× in this paper · explained in 2 episodes
• Nadia — 1× in this paper · explained in 2 episodes
• Pairwise Comparisons — 1× in this paper · explained in 2 episodes
• Progressive Disclosure — 1× in this paper · explained in 2 episodes
• Resource Constraints — 1× in this paper · explained in 3 episodes

Sources

• Evaluating Large Language Models Trained on Code
• Proof-or-Stop: Don't Trust the Agent, Trust the Evidence -- Loop Engineering for Verifiable Evidence-Gated Lifecycle Control
• SWE-EVO: Benchmarking Coding Agents in Long-Horizon Software Evolution Scenarios
• Meta-Harness: End-to-End Optimization of Model Harnesses
• Dive into Claude Code: The Design Space of Today's and Future AI Agent Systems
• Towards Iterative End-to-End Software Development: A Feature-Driven Multi-Agent Framework
• AutoHarness: improving LLM agents by automatically synthesizing a code harness
• ProjDevBench: Benchmarking AI Coding Agents on End-to-End Project Development
• GameCraft-Bench: Can Agents Build Playable Games End-to-End in a Real Game Engine?
• Terminal-Bench: Benchmarking Agents on Hard, Realistic Tasks in Command Line Interfaces
• SlopCodeBench: Benchmarking How Coding Agents Degrade Over Long-Horizon Iterative Tasks
• RefAgent: A Multi-agent LLM-based Framework for Automatic Software Refactoring
• MemGPT: Towards LLMs as Operating Systems
• ProgramBench: Can Language Models Rebuild Programs From Scratch?
• Advancing DRL Agents in Commercial Fighting Games: Training, Integration, and Agent-Human Alignment
• Self-Harness: Harnesses That Improve Themselves

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