Includes

curl "https://api.prophia.com/rest/v2/accounts/{accountId}/leases/{leaseId}?include=tags,subleases" \
  -H "X-API-Key: <your-api-key>"

Before and after

{
  "id": "prop_123",
  "propertyName": "Waterfront Plaza",
  "customId": "WFP-01"
}

{
  "id": "prop_123",
  "propertyName": "Waterfront Plaza",
  "customId": "WFP-01",
  "buildings": [
    { "id": "bld_456", "buildingName": "Waterfront Plaza — North Tower" },
    { "id": "bld_789", "buildingName": "Waterfront Plaza — South Tower" }
  ]
}

The rules

• One level deep, strictly. There is no include=buildings.leases — includes never chain. Walk the tree with successive requests instead: list buildings, then request each building with include=leases.
• Unknown keys are rejected with 400. Misspell a key and the error message lists every key the endpoint supports. This is deliberately stricter than sortBy, which silently falls back — don’t assume the two behave alike.
• Each key can require an extra capability. Your key needs the read capability for the embedded resource as well as the primary one — for example, GET /leases/{leaseId}?include=tags requires tag read on top of lease read. A request missing a capability is rejected with 403, not silently trimmed. See Errors and permissions.
• Absent ≠ empty. Responses omit fields that are null, so an include you didn’t request is missing from the JSON entirely. An empty array means you asked and there were none — branch on presence.

Supported keys by endpoint

What the keys mean

• properties / buildings / leases — the flat child list under the resource, limited to what your key is permitted to see.
• spaces — the building’s spaces, archived and non-archived alike. The dedicated spaces endpoint takes an archived filter; this key does not.
• documents — on properties and buildings: documents filed at that scope (rent rolls, stacking plans). On leases: per-document page geometry keyed by leaseDocId, for resolving a tag’s tagSelections[].docPageId references.
• tags — the consolidated DocTag list assembled from the lease’s documents, filtered by the lease’s current leaseType. Each tag carries only the spaces it applies to; see space-dependent and space-independent tags.
• subleases — lightweight refs (id, url, current leaseStatus/leaseSubStatus) to the lease’s subleases; an empty list means the lease has none.
• tagSelections — the tag’s citations: bounding boxes on document pages.
• pages — per-page geometry for the cited pages.
• applicableSpaces — the suite/floor list the tag applies to. See Spaces and encumbrances.