diff --git a/paths/qoc_checkupList_{setKey}.yaml b/paths/qoc_checkupList_{setKey}.yaml
index 2238439..8705108 100644
--- a/paths/qoc_checkupList_{setKey}.yaml
+++ b/paths/qoc_checkupList_{setKey}.yaml
@@ -103,6 +103,10 @@ get:
                         The title of this indicator
                       type: string
                       example: Bloeddruk
+                    key:
+                      description: Unique identifier, not to be shown to the user, for referring to this indicator in other API calls
+                      type: string
+                      example: ZEL-dm2-bp-result
                     optional:
                       description: |-
                         If present, this indicator is optional, and the value contains dutch human readable text explaining why.