Query device registry from frontend


For a custom card I am making, I would love to be able to query the device registry from the frontend to get all entities from a device.

Let me explain. I want to create a card that allows the user to define an entity. Whenever that card is clicked, I would like to query the device registry and find all the entities attached to the device this entity also belongs to.

I would then like to display these entities in a certain way, maybe a popup.

Is it possible to query the device registry using callWS and then get a result with all the entities connected to the device the configured entity is attached to?

I couldn’t find an endpoint for this in the API documentation.