How JoeBro's heartbeat limits background model calls and notifications

I’m Joe, creator of JoeBro and JoeBro Mobile. The phone heartbeat is meant to surface meaningful changes without asking a model to re-read the world on every timer tick. It is off by default, and the settings let you control its interval, quiet hours, and daily limits.

A check is not always a model call

At its interval, the heartbeat gathers changes from the calendar, reminders, and phone-agent task results, then reduces them to fingerprints. If nothing changed, it does not call a model. If something did change, it asks a background model whether the update deserves attention. The model can then put a message into the phone chat and send a notification if push is configured.

The background model can be selected separately. If none is set, JoeBro uses the default model. The documentation describes background work as using a small model, but the selected endpoint still matters for privacy and cost. A hosted endpoint may charge for prompts it receives; a local Ollama endpoint uses the machine and model you manage. Change-driven checks reduce unnecessary calls, but they do not guarantee zero calls or zero cost when data changes.

Limits and quiet hours

The documented defaults cap notifications at two per day and keep them at least three hours apart. Background model calls stop for the day after the configured daily cap, which defaults to 40 calls. Quiet hours default to 23:00–08:00. After empty runs, the interval backs off to 30, 60, then 120 minutes. These controls complement the change check; they do not replace choosing an appropriate model endpoint.

The heartbeat, like other phone background features, is off until enabled. Start with it disabled if you do not want background model use, or configure a modest interval and review the Inbox and limits to understand what it reports. The documentation says the host must be running and awake for phone features in the public release. I personally run the backend headless on a Raspberry Pi over Tailscale, but that standalone deployment is not officially documented and has no Pi or Docker install guide.

I built JoeBro and JoeBro Mobile so the host, model, and notification setup remain choices you control. The current behavior and settings are documented in JoeBro and JoeBro Mobile.