Coding Harness Plugins Are Agentic Systems

I didn&#x27;t set out to build an eval system for my coding-assistant plugins. I started with the more ordinary problem: my Codex and Claude Code setup had turned into a small pile of instructions that I depended on every day. There was a worktree plugin because I kept wanting feature work isolated from the main checkout. There was a PR babysitting plugin because "watch this until it merges" means…