Model Router Hook

Claude Model Router Hook

Effort-first model routing for Claude Code. Heuristics-first, opt-in autoswitch.

Install

The wizard asks whether to install globally and star the GitHub repository. Both prompts default to yes. Installation requires Claude Code and Python 3; starring requires an authenticated gh command. Restart Claude Code after installation.

Claude Model Router classifies each prompt by task and effort, then recommends the matching Claude model. It warns by default. Autoswitch is opt-in and only affects new sessions.

What it does

- Routes prompts with local heuristics and an optional Claude Code fallback.
- Uses Haiku only for clearly mechanical work; defaults agentic coding to Opus with graduated effort.
- Routes Agent and Task sub-agents when they spawn. Nested delegation is floored at the implementation target, and an explicit model always wins.
- Records the requested and resolved model for completed sub-agents, so host-side fallback or allowlist substitutions are visible.
- Dampens borderline classifications instead of switching tiers on weak evidence.

How it works

Errors fail open and leave the prompt unchanged. Prefix a prompt with ~ or
Alternative installs

Claude plugin manager

Manual

The manual installer prints the settings.json entries that you need to add.

Notes

- Activity is logged at ~/.claude/hooks/model-router-hook.log, including requested versus resolved sub-agent models.
- If another PreToolUse hook rewrites the same spawn, Claude Code's undocumented merge order decides which rewrite wins.

Project

Contributing | MIT license | Based on model-matchmaker by @coyvalyss1