pi-jev-router: a minimal Pareto-optimal OpenRouter model router for pi, based on Jev

Jev-classified model routing for pi.

Model rules

Writing tasks get STE and Humanizer rules. Code tasks run unit tests. Planning tasks get a structure check.

Commands

/router          show status
/router shadow   recommend only (default)
/router auto     switch models per task
/router off      stop routing
/router profile pareto_code | empirical_cost
/router budget <usd>

Benchmarks

node --experimental-strip-types eval/index.ts

Results: writing 89% cheaper. Code 88% cheaper with empirical_cost. Planning 100% pass on claude-sonnet-5.

Setup

npm install

Set OPENROUTER_API_KEY, or reuse the key stored in ~/.pi/agent/auth.json. Copy config/models.openrouter.json into ~/.pi/agent/models.json.

Auto-load globally:

mkdir -p ~/.pi/agent/extensions
ln -sf ~/Documents/GitHub/pi-jev-router ~/.pi/agent/extensions/pi-jev-router

Then start pi normally (no -e required).

Worktree isolation

Workers dispatched via dispatch_task execute in isolated Git worktrees:

• Worker edits code on a separate task branch (task/<id>).
• If verifierCommand passes (exit 0), changes merge cleanly into the repository.
• If verification fails or aborts, the worktree is cleaned up without leaving dirty changes.

Files

• src/classifier.ts — Jev call. One request, five questions.
• src/selector.ts — policy. No model calls.
• src/board.ts — SQLite task state.
• src/dispatch.ts — worker spawn and handshake.
• extensions/router.ts — pi hooks and commands.
• eval/ — benchmark tasks, verifiers, runner.