> TL;DR: AI-safe engineering needs three durable, machine-readable layers: a behavior layer what the product must do, a decisions layer why the team chose it, and an execution layer what's actually running and whether it matches. Execution has mature...

> TL;DR: Vibe coding ships fast, but it often fails to preserve the reasoning behind product behaviors — and agents refactoring later will “reasonably” change things users rely on. A lightweight behavior spec .pbc.md makes “what must happen / must no...

> TL;DR: CLAUDE.md and AGENTS.md are excellent at steering how agents write code. They were never designed to capture what the product promises to do. When agents refactor, extend, or integrate code, they need a behavior spec — not more workflow inst...

> TL;DR: The agent ecosystem is rapidly improving harnesses, memory, and workflow rules — but agents still lack product truth: which behaviors are protected promises vs. incidental implementation. This post argues that missing layer is a durable beha...