Nine Engineers, 1,211 PRs: Microsoft's Agent Insanity

🔥 What happened A nine-person Microsoft team merged 1,211 pull requests into Copilot Cowork's main branch in a single day – most written by AI agents. The product went from empty repo to worldwide GA in four and a half months, then swapped its runtime from Python to Rust while live. 💡 Why it matters The bottleneck moved: agents aren't the slow part, vague specs are. Microsoft's fix – a markdown spec before any code – pushed monthly merged PRs from 257 in January to 2,754 in May. Agents run credential-free in containers; a trusted host gates every action. ⚡ Our take The PR count is a stunt. The real lesson is boring: write better specs. Teams chasing agent velocity without that discipline are just generating expensive rework.