ci and testing

The ci and testing tag explores how modern software repositories document and standardize engineering practices around builds, tests, linting, and code review. Its current focus includes AGENTS.md, a plain-English repository file that instructs coding agents how to work within a project. Examples from production repositories such as OpenAI Codex, Sentry, Apache Airflow, Temporal, Cloudflare’s Workers SDK, and Coder show these files evolving from experimental prompt instructions into reviewable engineering infrastructure. The discussion connects repository policy with practical knowledge that has traditionally appeared in CI failures, pull-request feedback, and the experience of senior engineers.