Pi Jev Router

A Pi extension that asks Jev to classify each new text task, then selects a cheap or expensive chat model for the task. It works with Pi 0.87.1+ and Node 22.6+.

Install with Pi

Install from npm:

pi install npm:@dimivelev/pi-jev-router

Or install directly from GitHub:

pi install git:github.com/dimivelev/pi-jev-router

The unscoped pi-jev-router package on npm is maintained by someone else; use the @dimivelev scope for this project. Restart Pi or run /reload, then run /jev-router to open the settings menu. During development, load directly with pi --extension ./index.ts from this directory.

Default configuration

• Jev backend: OpenCode Zen, model jev-1.13-free (OpenCode marks it limited-time)
• Cheap chat model: opencode-go/deepseek-v4-flash
• Expensive chat model: openai-codex/gpt-6-astra
• Minimum Jev probability for the cheap tier: 0.7
• Automatic routing: off until first /jev-router on; /on remembers the choice for new sessions and /off clears it

The menu can switch to standard OpenCode Zen jev-1.13, TypeSafe direct (jev-latest), or a custom Jev-compatible /systemone endpoint. OpenCode Zen is separate from the Go subscription; OpenCode's current published Go model list does not include Jev.

The menu also edits the cheap/expensive Pi model pair and probability threshold. It verifies model availability, text input support, authentication, and Pi's enabledModels/--models scope.

API keys

Set the environment variable for the selected backend before starting Pi, or enter the key masked in the menu. Menu-entered keys are remembered separately from settings in ~/.pi/agent/jev-router-secrets.json with mode 0600. The file contains plaintext keys readable only by your OS user; use environment variables instead if you do not want keys stored on disk. Saved keys take precedence over environment keys for the same backend.

• OpenCode Zen: OPENCODE_API_KEY
• TypeSafe: TYPESAFE_API_KEY
• Custom endpoint: JEV_ROUTER_CUSTOM_API_KEY (optional if the endpoint does not require auth)

API keys are not written to the ordinary settings file or repository. A saved menu key takes precedence over its environment variable; “Clear saved/session API key” removes it and falls back to the environment. For environment-managed keys, export the variable in the shell/service that launches Pi; .env.example is a reference only, since Pi does not load .env files automatically.

Custom endpoint safety

Enter the complete URL ending in /systemone. HTTPS is required; plain HTTP is allowed only for localhost. URLs with credentials, query strings, or fragments are rejected. Redirects are disabled, and the menu asks you to confirm the custom host before saving it. Do not embed credentials in the URL; use the masked key field or JEV_ROUTER_CUSTOM_API_KEY.

Non-secret settings are saved to ~/.pi/agent/jev-router.json with mode 0600. Custom endpoints receive the task text and any custom API key configured for that backend, so use only a service you trust.

Routing behavior

• Jev answers a Noul question with a direct probability that the task is simple enough for the cheap model.
• Probabilities at or above the configured threshold select cheap; lower, malformed, or missing scores select expensive.
• Jev errors/timeouts and prompts over 12,000 characters fail toward expensive.
• Prompts with images skip Jev and retain the current model.
• Pi restores the pre-router model after the task completes.

Only the current expanded prompt text is sent to Jev. Conversation history and image data are not sent; expanded @file or prompt-template text may be part of the prompt. Requests time out after six seconds. Provider usage charges may apply.

Optional environment overrides (a saved menu setting takes precedence):

export JEV_ROUTER_CHEAP_MODEL="provider/model-id"
export JEV_ROUTER_EXPENSIVE_MODEL="provider/model-id"
export JEV_ROUTER_CHEAP_PROBABILITY="0.7" # 0..1
export JEV_ROUTER_AUTO=1                    # force auto-start on; 0 forces it off

Commands

• /jev-router or /jev-router menu — open settings
• /jev-router on — enable routing and remember auto-start for new sessions
• /jev-router off — disable routing for this and future sessions; restore the prior model
• /jev-router status — show backend, key source (never the key), auto-start, models, threshold, and the last Jev probability

Development

No npm dependencies are required. Run the tests with:

npm test

The tests mock network calls and cover Noul/Choice routing, the TypeSafe/OpenCode Zen/custom APIs, settings and secret-file permissions, menu behavior, masked key persistence, and auto-start behavior.

Publishing (maintainers)

The package is configured as a public, scoped Pi package under the MIT license. To release a new version, sign in with an npm account authorized to publish under @dimivelev, then inspect the tarball and publish:

npm login
npm test
npm pack --dry-run
npm publish

The publish command runs the test suite again. Increase the version in package.json before subsequent releases; npm does not allow republishing an existing version. No API keys or local settings files should appear in npm pack --dry-run.

References

• TypeSafe API quick start
• OpenCode Zen Jev
• OpenCode Go model list
• Pi extension documentation