Plan-and-Execute Multi-Agent Pattern: Frontier Planner + Cheap Executor Nodes for 90% Cost Reduction

Codebridge·high signal

The Plan-and-Execute pattern routes all strategic decomposition and tool-use planning through a frontier model (Opus 4.6 or GPT-5.2) while delegating each individual execution step to a smaller, cheaper model — reducing inference costs by up to 90% compared to using the frontier model end-to-end, according to 2026 multi-agent benchmarking. The key implementation detail is that the planner produces a fully validated task graph before any executor runs, catching dependency errors and ambiguous steps before expensive worker tokens are spent. This mirrors the ReWOO static-plan approach but explicitly optimizes for per-node model tier selection.