Architecture pattern
Cascade router
A cheap decision chooses whether to use rules, a small model, a premium model, a specialist, or a human.
Plausible
What the pattern does
A cheap decision chooses whether to use rules, a small model, a premium model, a specialist, or a human.
Caveat
Bad routing can erase all cost savings through failures and retries.
Patterns are recurring shapes observed across the collected material. A repeated shape is evidence that developers converge on it, not evidence that it performs well in production.
Sources
Limitations
- Bad routing can erase all cost savings through failures and retries.
Where this pattern appears
- MAGI System on Jev ObservedAn open-source three-sage voting experiment inspired by Neon Genesis Evangelion.
- Agent Model Router Authored HypothesisA drop-in router that selects model, reasoning effort, and fallback policy per step.
- The strongest near-term architecture is Jev as a complement and control layer around generative models. PlausibleJev produces decisions rather than prose, and Vercel exposes it through an evaluation-oriented API.
- typesafe-mcp ObservedAn MCP server exposing TypeSafe evaluation to coding agents.