Three filters are AND-combined with modified_since on the list endpoint:
| Query parameter | Behaviour |
|---|---|
object_number=<string> | Exact match on the ERP grouping key. Returns every row that shares the value — Mercura's master-project concept treats them as one logically but exposes them as distinct rows. |
request_id=<int> | Returns the single project linked to the request via Request.project_id. Empty page for requests with no project FK. |
status=<UPPERCASE> | Restrict to one lifecycle status. Unknown values return 400 VALIDATION_FAILED. |
Combine object_number with request_id when you need to verify that a specific request rolls up under a specific ERP grouping key.