diff --git a/apify-api/openapi/components/schemas/actor-runs/Run.yaml b/apify-api/openapi/components/schemas/actor-runs/Run.yaml
index c9b5c78c71..88f4790290 100644
--- a/apify-api/openapi/components/schemas/actor-runs/Run.yaml
+++ b/apify-api/openapi/components/schemas/actor-runs/Run.yaml
@@ -93,18 +93,21 @@ properties:
     nullable: true
     example: master
   usage:
-    allOf:
-      - oneOf:
-          - nullable: true
-          - $ref: ./RunUsage.yaml
-      - {}
+    nullable: true
+    $ref: ./RunUsage.yaml
   usageTotalUsd:
     type: number
     nullable: true
+    description: >-
+      Total cost in USD for this run. Represents what you actually pay.
+      For run owners: includes platform usage (compute units) and/or event costs depending on the Actor's pricing model.
+      For non-owners: only available for Pay-Per-Event Actors (event costs only).
+      Not available for Pay-Per-Result Actors when you're not the Actor owner.
     example: 0.2654
   usageUsd:
-    allOf:
-      - oneOf:
-          - nullable: true
-          - $ref: ./RunUsage.yaml
-      - {}
+    nullable: true
+    description: >-
+      Platform usage costs breakdown in USD. Only present if you own the run AND are paying for platform usage
+      (Pay-Per-Usage, Rental, or Pay-Per-Event with usage costs like standby Actors).
+      Not available for standard Pay-Per-Event Actors or Pay-Per-Result Actors owned by others.
+    $ref: ./RunUsage.yaml