Ponytail vs a good AGENTS.md: What we found on our real codebase

An evaluation of the Ponytail plugin for coding agents on a real monorepo showed that while it successfully reduced lines of code and costs, it also led to missed requirements on complex tasks compared to an existing, extensive AGENTS.md rule setup. Instead of adopting the plugin, the team integrated key concepts into their own configuration and published their engineering playbook as an open-source resource on GitHub. Open article →