diff --git a/docs/docs.go b/docs/docs.go
index 1b27101..15be624 100644
--- a/docs/docs.go
+++ b/docs/docs.go
@@ -1471,7 +1471,7 @@ const docTemplate = `{
                     },
                     {
                         "type": "integer",
-                        "description": "Optional exclusive end in epoch milliseconds; aligned down to a complete bucket, at most 30 days old",
+                        "description": "Optional exclusive end in epoch milliseconds; aligned down to a complete bucket, at most 30 days old. Activity uses this window; summary freshness/latestRecordedAt and the last complete hour are measured at response generation time, independently of until.",
                         "name": "until",
                         "in": "query"
                     }
diff --git a/docs/swagger.json b/docs/swagger.json
index 52df28f..96ef7bd 100644
--- a/docs/swagger.json
+++ b/docs/swagger.json
@@ -1469,7 +1469,7 @@
                     },
                     {
                         "type": "integer",
-                        "description": "Optional exclusive end in epoch milliseconds; aligned down to a complete bucket, at most 30 days old",
+                        "description": "Optional exclusive end in epoch milliseconds; aligned down to a complete bucket, at most 30 days old. Activity uses this window; summary freshness/latestRecordedAt and the last complete hour are measured at response generation time, independently of until.",
                         "name": "until",
                         "in": "query"
                     }
diff --git a/docs/swagger.yaml b/docs/swagger.yaml
index 4fda3a4..144e621 100644
--- a/docs/swagger.yaml
+++ b/docs/swagger.yaml
@@ -2432,7 +2432,9 @@ paths:
         name: interval
         type: string
       - description: Optional exclusive end in epoch milliseconds; aligned down to
-          a complete bucket, at most 30 days old
+          a complete bucket, at most 30 days old. Activity uses this window; summary
+          freshness/latestRecordedAt and the last complete hour are measured at response
+          generation time, independently of until.
         in: query
         name: until
         type: integer