265 Dead Entities: Cleaning Up a Home Assistant Registry

Over time, your smart home accumulates ghosts. Devices you removed months ago still have entries in the entity registry. Integrations you disabled leave behind orphaned entities. After a year of tinkering with Home Assistant, I had 265 entities that either didn't exist, were duplicated, or pointed to removed devices.

The Accumulation Problem

Every time you add a Zigbee device, set up an integration, or create a helper entity, Home Assistant registers it. But when you remove the device or disable the integration, the registry entry often stays. Over time, this builds up:

• Unavailable entities: 100+ entities showing as "unavailable" because their devices were removed
• Duplicates: Entities created twice due to re-pairing or integration re-setup
• Stale integrations: Entities from integrations that were disabled months ago
• Test artifacts: Entities created during testing that were never cleaned up

The UI lets you delete entities one at a time, but 265 clicks is not how I want to spend my evening.

The WebSocket API: Your Scalpel

Home Assistant exposes a WebSocket API that gives you programmatic access to the entity registry. This is different from the REST API — it's a persistent WebSocket connection that accepts JSON commands.

The connection is straightforward:

import websocket, json

ws = websocket.create_connection(
    "ws://homeassistant.local:8123/api/websocket",
    header={"Authorization": f"Bearer {TOKEN}"}
)

# Auth is handled by the first message
auth_req = json.loads(ws.recv())
ws.send(json.dumps({"type": "auth", "access_token": TOKEN}))
auth_result = json.loads(ws.recv())

Listing All Entities

Once connected, you can list the entire entity registry:

ws.send(json.dumps({
    "type": "config/entity_registry/list"
}))
entities = json.loads(ws.recv())["result"]

This returns every entity with its metadata: entity_id, platform, device_id, disabled_by, and more. I filtered for entities that were either unavailable, disabled, or had no corresponding device.

The Safety Checks

Bulk deletion is dangerous. Before removing anything, I ran three safety checks:

1. Is the entity currently in use by any automation? Cross-referenced against all automation configs
2. Is the entity referenced in any dashboard? Checked all Lovelace dashboard configurations
3. Is the entity disabled vs truly orphaned? Disabled entities might be intentionally disabled; orphaned ones are the target

Entities that passed all three checks were added to the deletion list. This reduced the count from 265 to 198 actually-safe-to-remove entities. The remaining 67 were either in use or intentionally disabled.

Bulk Removal

The actual removal uses the entity registry's remove command:

for entity_id in to_remove:
    ws.send(json.dumps({
        "type": "config/entity_registry/remove",
        "entity_id": entity_id
    }))
    result = json.loads(ws.recv())
    if result.get("success"):
        print(f"Removed: {entity_id}")
    else:
        print(f"Failed: {entity_id} — {result}")

The whole operation took about 30 seconds. 198 entities removed successfully, 0 failures.

The Result

After cleanup:

• Entity count dropped by 40%
• Dashboard loading time improved noticeably
• No more "unavailable" clutter in the entity list
• Zero broken automations (the safety checks worked)

Lessons

• The WebSocket API is powerful. Home Assistant's REST API gets all the attention, but the WebSocket API is where the real registry operations live.
• Always check dependencies before removing. Automations and dashboards will silently break if you remove entities they reference.
• Do this quarterly. Entity rot is inevitable. A quarterly cleanup keeps things manageable.
• Script it. 265 manual clicks is unacceptable. 30 seconds of script is not.