# Get last-received observation ids for a device

Canonical page: https://docs.ovok.com/api/slim/telemetry/get-last-received-observation-ids-for-a-device

`GET /v1/slim/telemetry/{deviceId}/lastIds`

Returns, for one device, the ids of the most recent Observations received for heart rate, respiratory rate, sleep status and presence, plus the latest batch. Unlike `effectiveIds`, these change on every reading, whether or not the displayed value changed.

**Auth:** bearer token. The caller must be a practitioner, an admin or a System Owner, and needs `Device:read`.
**Scope:** a device identifier only resolves when the device is visible to your token and in the caller's project.

## Behaviour

- `deviceId` is either the device identifier or the Device resource id (a UUID).
- Each field is an Observation id, or `null` when nothing has been received for it yet.
- Only devices whose readings carry their own Observation id fill these fields. For other devices every field is `null`.
- A device that is not found returns every field `null`, not an error.
- Lookups of a device are cached for up to 10 minutes, and misses for 30 seconds.

## Example

```bash
curl -X GET 'https://api.sandbox.ovok.com/v1/slim/telemetry/c3499c27-2973-0a7f-807e-fb8676a92dcb/lastIds' \
  -H 'Authorization: Bearer eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpYXQiOjE3NjcyNjg4MDAsImV4cCI6MTc2NzI3MjQwMH0.Ql3B_ztDvctlyZ2z0vp4sl3ExXRQGkzmxdmTAqxNzZk'
```