Cortex: Measurement-Gated Evolution and Pruning of Coding-Agent Skills and Rules

Key points

• We call these files the agent's harness.1
• Developers add to it whenever they correct the agent, but one success proves little: the same agent can pass a task once and fail it the next time.1
• We present Cortex, a tool that tests changes to the harness instead of trusting them.1
• We tested Cortex with Claude Haiku 4.5 on a repository built for the purpose, with conventions the model tends to break, one area with nothing to learn, and a script playing the developer.1

Sources (2)

• [1]Cortex: Measurement-Gated Evolution and Pruning of Coding-Agent Skills and Rules
  arXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 9, 06:29 PM

  Coding agents such as Claude Code also follow text files that developers write for them: a project file, skills the agent may choose to open, and rules that load automatically when the agent reads matching files.

  We call these files the agent's harness.

• [2]Cortex: Measurement-Gated Evolution and Pruning of Coding-Agent Skills and Rules
  Hugging Face Daily Papers · Oct 9, 12:00 AM · same content

Extractive summary: sentences quoted from the sources.