MCP app UIs

Hosts that support MCP Apps render most tool results as an inline widget instead of raw JSON. The nine UIs are embedded in the binary and served as ui://polar-flow/*.html resources; each tool advertises its UI in _meta.ui.resourceUri. Hosts without MCP-app support get the same data as the usual text/JSON result.

The screenshots below use sample data.

Sessions — sessions.html

Tools: list_training_sessions, get_training_session_summary, get_training_session_details, edit_training_session.

The list renders one card per session, newest first:

Clicking a card calls get_training_session_summary from inside the widget and drills into the summary — duration, distance, pace or speed (per sport), heart rate, calories, training load and time in each heart-rate zone, plus the session’s feeling (1–5 dots) and note when set. edit_training_session returns the edited session in this same summary view:

Details › under the summary — or a get_training_session_details result — opens the detail view: the totals, the heart-rate zone bar, an intervals table when the session was started from a planned target (one row per rep: time, distance, pace or speed, HR, power, target zone and the share of time spent in it), laps when recorded, and the heart-rate, pace (or speed), power and altitude curves with the reps marked along the top. Hovering the curves reads out the values at that moment.

The curves are not part of the tool result. The widget fetches them itself with get_training_session_samples at about 600 points, so the per-second data never enters the conversation.

Training targets — targets.html

Tools: list_training_targets, get_training_target, create_training_target, update_training_target.

A single target shows its phases — warm-up, repeat blocks with work and rest, cool-down — with each goal and heart-rate zone:

Favorites — favorites.html

Tools: list_favorites, get_favorite, create_favorite, update_favorite, rename_favorite, set_favorite_sport, save_target_as_favorite, schedule_favorite.

The list shows one card per favorite with its sport, type (volume, phased, route) and goal (distance, duration, calories). A single favorite shows its description and, for phased favorites, the same phase cards as a training target. schedule_favorite shows a confirmation with the new target id, date and time.

Imported routes appear in the list, but import_route and get_route have no widget yet: they return text/JSON only.

Calendar — calendar.html

Tools: get_calendar_events, get_calendar_week_summary.

Progress — progress.html

Tool: get_progress_summary.

User — user.html

Tool: get_user_info.

Training zones — zones.html

Tools: get_training_zones, create_sport_profile, update_training_zones (the write tools add a line saying what was saved).

Daily activity — activity.html

Tool: get_daily_activity. A range shows steps per day and each day’s time by intensity; a single day shows its headline numbers and the intraday activity and heart-rate curves.

Sleep — sleep.html

Tool: get_sleep. One row per night: a hypnogram strip (light / deep / REM / awake), time asleep, bed and wake times, Sleep Score and continuity, with averages for the range.

Notices — every UI

A call with no data to show renders a notice card instead of staying on “Loading…”:

• Rejected (red): the tool returned an error, e.g. an argument over Polar’s limit. The card shows the error text.
• Nothing to show (blue): a plain statement such as No target with id 7. These results carry a {"type": "notice", "kind": "notice", "message": …} structured payload.
• Cancelled (grey): the user declined a confirmation ("kind": "cancelled"), or the host cancelled the call.

If no result reaches the UI within 20 seconds, it says so; a result that arrives later still replaces the card.