Magic Compose

Let Jev decide where a thread runs

Magic Compose adds a wand button beside the send button in the new-thread composer. Switch it on and start typing: Jev, TypeSafe's fast classifier model, picks the project, the machine, the model, the reasoning level, and the environment, and the composer's pickers move to its answer as you type.

You see every choice before it runs

Nothing is hidden and nothing is sent for you. The send button waits, usually a fraction of a second, until the pickers match what you wrote, so what runs is what you were shown. Change any picker you disagree with and it stays put. Switch Magic Compose off and the composer is exactly as it was.

Tell it how you work

Settings → Magic Compose is laid out by the question Jev answers: projects, machines, environments, models and effort. Each has the list Magic Compose may choose from and, beside it, plain-English instructions for choosing, such as “Use Fable for UI design and planning, Opus for most other tasks, Sonnet for simple tasks” or “iOS work must run on the MacBook.” Costly run modes like ultracode stay off unless you turn them on.

You also decide how much Magic Compose does. Choose which pickers it may set, whether send waits for it, and whether it asks Jev as you type or only when you pause.

Machines it understands

Each connected machine reports its operating system, CPU load, memory, free disk, and how many agent threads it is running. Jev sees that alongside your instructions, so an iOS task lands on a Mac and ordinary work goes to a machine that is idle.

Tuned from your own history

Ask an agent to tune Magic Compose and the bundled skill reads which model and effort you picked for the threads you started, writes the rotation and instructions to match, and backtests them against those choices.

Try it first

Try it in settings, or bb magic-compose route "<prompt>", shows where a prompt would go and how sure Jev was, without starting anything.

Requirements

Requires BB 0.43 or later, Plugin SDK 0.4.103 or later, and an API key for a gateway that serves Jev: the Vercel AI Gateway or OpenRouter. With Magic Compose on, your prompt is sent as you type, not only when you send it. Each decision sends your prompt so far, your instructions, and the names, folders, and recent thread titles of your projects, plus machine names and load, to TypeSafe through that gateway. A decision costs a small fraction of a cent, and a prompt takes ten or so. Vercel's free tier allows only about 10 Jev calls per 5 minutes, which Magic Compose uses up within one prompt; any Gateway credit lifts that.