How can I get zero values to differentiate no detections versus a non-functional sensor?

Add "filter.value.gte = 0" to get zero values.

Using the Reporting endpoint, you can get zero values from when no people are detected under the sensor by adding filter.value.gte = 0.

All sensors send us data even including zeroes, whereas a non-functional sensor will not send data at all.

"group_by": {
"order": ["space_id"],
"raw": true
"window": {
"every": "5m",
"function": "max"
"filter": {
"start": "-1d",
"value": {
"gte": 0