🔧 The Agent Stack in 2026: Layers, Harnesses, and Where You Actually Build

Two releases in early April 2026 sparked a lot of strong takes: Anthropic's Claude Managed Agents (public beta, April 8) and LangChain's Deep Agents Deploy (a few weeks earlier). Some people called it a fundamental shift in agent development. Others called it framework churn in a trench coat.

Before arguing either way, it's worth stepping back to...