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jev-model-router

Route Claude Code model tiers and reasoning effort with one parallel Jev classification.

What Jev decides

Which fast, balanced, or deep tier fits the work, how much reasoning it needs, and whether production risk requires escalation.

The mod asks Jev for a task tier, reasoning score, and production-risk probability, then applies asymmetric confidence gates before changing a subagent model or the main loop’s effort.

CHOICESCORENOUL
Jev role
Classify task complexity, required reasoning effort, and operational risk before a Claude Code turn runs.
Input
The submitted prompt or subagent task, configured tier criteria, supported effort choices, and routing policy.
Output
A tier Choice, effort Score, and risk Noul probability with available confidence values.
Decision frequency
At prompt submission for the main turn and when a routed subagent is spawned.
Fallback
Keep the engine’s original model and effort on timeout, malformed output, or low confidence; use the built-in classifier when no external key is configured.
Author reported · Source reviewed

How it works

Input
The submitted prompt or subagent task, configured tier criteria, supported effort choices, and routing policy.
Jev
CHOICE + SCORE + NOUL
Output
A tier Choice, effort Score, and risk Noul probability with available confidence values.

Overview

jev-model-router is an early-access mod inside the claude-code-templates repository. At prompt submission it evaluates three questions in parallel: a Choice over work tiers, a Score for reasoning effort, and a Noul-style risk check. Local policy maps those answers to configured models and supported effort levels.

Downgrades require a higher confidence than upgrades because undersizing a task is costlier than spending extra model capacity. Risk above the configured threshold selects the deep tier. Main-loop model switching is disabled by default because it can invalidate prompt caching, while subagent model routing and main effort routing are enabled. The mod requires Claude Code function hooks and documents that the API may change.

Language
TypeScript
License
MIT
Author
claude-code-templates contributors
Sources checked Sep 21, 2026

Sources

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