Cadre

Role Specialization — Planner, Critic, Executor, Verifier

The most common multi-agent decomposition in 2026: one agent plans, one executes, one critiques or verifies. MetaGPT (arXiv:2308.00352) formalizes this as SOPs encoded into role prompts — Product Manager, Architect, Project Manager, Engineer, QA Engineer — following `Code = SOP(Team)`. ChatDev (arXiv:2307.07924) chains designer, programmer, reviewer, tester through a "chat chain" with "communicative dehallucination" (agents explicitly request missing details). The verifier is load-bearing: Cemri et al. (MAST, arXiv:2503.13657) show every multi-agent failure can be traced to missing or broken verification. PwC reported 7× accuracy gain (10% → 70%) from structured validation loops in CrewAI.

Learn + Build 1 hr Python (stdlib)

Prerequisites: Phase 16 · 04 (Primitive Model), Phase 16 · 05 (Supervisor)

#Problem

Generic multi-agent systems produce generic output. Three coders in a group chat write three flavors of the same mediocre code. You can add more agents, add more rounds, and still not cross the quality threshold.

The fix is not more agents — it is different agents. Assign distinct roles. Give the critic tools the planner does not have. Give the verifier an objective test suite. Now the system has internal disagreement with grounded correction, not just parallel guessing.

#Problem

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