The 9-Layer Agentic AI Stack

Most organizations bolt agents onto their stack one experiment at a time — and then wonder why nothing survives contact with production. This article lays out the full nine-layer stack a production agent actually stands on: from infrastructure and model serving up through orchestration, memory, tool access, evaluation, observability, security, and governance.

The argument is simple: every layer you skip becomes an incident you'll debug later. The piece maps what each layer owns, where the common failure modes hide, and how the layers compose into a system an enterprise can actually operate, audit, and defend.