Your session on a BUSY Bar
What is a BUSY Bar? A wall-mounted display with two screens, built to be read from across the room. Round & Rest mirrors the current session on it — phase, block, round and clock — without losing sight of what the device can do, and what it cannot.
What the bar shows
The current phase, the block number, the round and the clock: the essentials of a session, condensed onto a screen built for a glance rather than a read. The phase label stays in a small font on the front — at a larger size it crowded the block number, the piece of information that matters most in the middle of a run of blocks.
On the front screen, the background colour reuses the same palette as the phone: a saturated block per phase, readable without leaning in, whether the room is dim or sitting in full sun by a window. The rear screen is greyscale and cannot carry the phase colour: it ranks by size and weight instead.
One request per phase, not per second
The bar keeps its own countdown: it is sent a timestamp, and it counts down on its own until the next phase. That is what makes the integration viable over an ordinary gym network — and it is a design choice, not a limitation suffered. A request every second was tried: the device's native countdown is capped at five pixels tall, and redrawing it as text every second was the only way to get a bigger clock. The gain was real — it cost one request per second, and that price was judged too high.
Why a relay
The BUSY API emits no CORS header and rejects every preflight
request: a browser cannot talk to it directly without being blocked.
Calls go through a relay, https://mcp.roundandrest.com/bar,
never straight from the phone itself.
What the bar does not do
Can the bar pause the session? No, and that is not a design choice: the device simply exposes no key-press event to listen to, only a way to inject one. The channel is one-way — you get the BUSY Bar's screen or its buttons, never both at once. Pausing, moving to the next phase, all of it happens from the phone; the bar only displays.
Do you need a BUSY Bar to use Round & Rest? No. It is an extra display, not a dependency: without it, the session runs exactly as it does on a phone lying on the floor, full-frame screen and cues included.
What is still open
Control from the bar itself — pausing or moving to the next phase without touching the phone — stays closed as long as the device exposes no key-press event. The upcoming features page details what is planned, and what is deliberately left out.
OPEN THE TIMER — 30 / 30 × 10Without a bar the timer works the same. With one, the session goes on the wall.
REQUEST AN INTEGRATIONAn address, not a form. Say which device or which service.
Other pages
- Integrations MCP, URL configuration, and the BUSY Bar as a whole.
- Connect Claude or ChatGPT The address to paste, step by step.
- Timer for CrossFit The four formats of a box, displayable on the bar.