Door, window, and garage left-open alerts in Slack

Build an agent workflow that acts as a smart "left open too long" watchdog for my home. It should run on a cron trigger every 10 minutes and decide, with judgement, whether anything is genuinely worth alerting me about.

Step 1: scan the house. Call Home Assistant List States and filter to entities that look like doors, windows, and the garage. Use entity_id patterns like binary_sensor.*_door, binary_sensor.*_window, and cover.garage*. Treat any of these as a candidate if its current state is "open" (for covers, treat "open" or any non-closed state as open).

Step 2: confirm duration. For each candidate, call Home Assistant Get History scoped to that entity over the last few hours and figure out how long it has actually been continuously open. Apply configurable thresholds: 15 minutes for interior doors and windows, 5 minutes for the garage. Anything under threshold is ignored.

Step 3: grab visual context. If a camera entity is mapped to the area (for example camera.garage for cover.garage_door, or a camera in the same room as the sensor), call Home Assistant Get Camera Screenshot on that camera and include the image or a link in the alert.

Step 4: reason before alerting. Take into account time of day and day of week (garage open at 2pm on a Saturday is probably fine, garage open at 2am is not), how long it has been open relative to the threshold, and whether I have already been notified about this exact open session recently. Suppress duplicate alerts within the same continuous open session, even across runs, so I get one message per opening, not one every 10 minutes.

Step 5: tell me. For each opening that survives the reasoning step, send a single concise Slack message using Slack Bot Send a Message to a channel or DM I will configure. Each message should include the friendly name of the entity, where it is, how long it has been open, the snapshot (or link) if available, and a one-line plain-English summary like "Garage door has been open for 42 minutes. Looks unusual for 11pm on a Tuesday." If nothing is worth alerting on, send nothing.

Keep the message minimal and human, no emoji walls or technical jargon. The whole point is that I trust the alert because the agent only fires when it is actually worth my attention.