diff --git a/.generator/schemas/v2/openapi.yaml b/.generator/schemas/v2/openapi.yaml
index e6df2f158a6..abcdf549631 100644
--- a/.generator/schemas/v2/openapi.yaml
+++ b/.generator/schemas/v2/openapi.yaml
@@ -78234,8 +78234,10 @@ paths:
         schema:
           example: 3653d3c6-0c75-11ea-ad28-fb5701eabc7d
           type: string
-      - description: Retrieves the on-call user at the given timestamp (ISO-8601).
-          Defaults to the current time if omitted."
+      - description: Retrieves the on-call user at the given timestamp in RFC3339
+          format (for example, `2025-05-07T02:53:01Z` or `2025-05-07T02:53:01+00:00`).
+          When using timezone offsets with `+` or `-`, ensure proper URL encoding
+          (`+` should be encoded as `%2B`). Defaults to the current time if omitted.
         in: query
         name: filter[at_ts]
         schema:
diff --git a/lib/datadog_api_client/v2/api/on_call_api.rb b/lib/datadog_api_client/v2/api/on_call_api.rb
index 1ad0475daab..2cc14e5581b 100644
--- a/lib/datadog_api_client/v2/api/on_call_api.rb
+++ b/lib/datadog_api_client/v2/api/on_call_api.rb
@@ -791,7 +791,7 @@ def get_schedule_on_call_user(schedule_id, opts = {})
     # @param schedule_id [String] The ID of the schedule.
     # @param opts [Hash] the optional parameters
     # @option opts [String] :include Specifies related resources to include in the response as a comma-separated list. Allowed value: `user`.
-    # @option opts [String] :filter_at_ts Retrieves the on-call user at the given timestamp (ISO-8601). Defaults to the current time if omitted."
+    # @option opts [String] :filter_at_ts Retrieves the on-call user at the given timestamp in RFC3339 format (for example, `2025-05-07T02:53:01Z` or `2025-05-07T02:53:01+00:00`). When using timezone offsets with `+` or `-`, ensure proper URL encoding (`+` should be encoded as `%2B`). Defaults to the current time if omitted.
     # @return [Array<(Shift, Integer, Hash)>] Shift data, response status code and response headers
     def get_schedule_on_call_user_with_http_info(schedule_id, opts = {})