---
type: "synthesis"
sources: ["agentic"]
tags: ["orchestration", "foundation-models", "architecture"]
id: "cross-multi-model-orchestration"
sourceVaultSlug: "hbr-seg-agentic"
originDay: 6
articleStem: "hbr-seg-agentic"
sourceUrl: "(unified vault: 9 sources)"
sourceTitle: "HBR — Firm Ⅱ-A · Agentic operating model / brand code / workstreams"
---
Two articles describe the plumbing that coordinates many agents — and they complement each other precisely.

A002 describes the *vertical* architecture: the four-layer [[framework-platform-layers]], where the [[concept-orchestration-layer]] is the "central nervous system" routing tasks between specialized [[concept-execution-layer|execution agents]] and escalating to the [[concept-interface-layer|human interface]]. It's a [[concept-team-of-digital-teams]].

A028 describes the *horizontal* diversity that should populate those layers: [[concept-structural-ai-diversity]] means the reasoning, generation, and evaluation layers should draw on *different vendors' foundation models* (Claude reasons, Gemini evaluates, GPT generates) to avoid [[concept-correlated-ai-errors]] and produce [[concept-cognitive-friction]]. Governed by [[concept-model-portfolio-governance]].

A058 supplies the *operational* discipline: [[concept-ai-orchestration]] as a managed function (multi-agent orchestration) with [[framework-ai-orchestration-responsibilities]].

**The combined picture the corpus never states in one place:** a mature agentic system is A002's layered orchestration architecture, populated by A028's diverse multi-vendor models, run by A058's [[concept-agent-manager|agent managers]], and grounded in a shared [[concept-brand-code]]/[[concept-judgment-infrastructure]]. The open engineering questions compound: A002 asks how to stop [[question-hallucination-orchestration|cascading errors]], A028 asks how to [[question-measuring-cognitive-friction|measure productive friction]], and A017 asks how [[question-legacy-vendor-adaptation|legacy vendors]] will expose APIs (via [[entity-mcp]]) to make any of this possible. Together they define the frontier — see [[cross-homogeneity-trap]] and [[cross-oversight-paradox]].