diff --git a/placement-api-ref/source/parameters.yaml b/placement-api-ref/source/parameters.yaml
index 8d746ae707f2..e30706547e02 100644
--- a/placement-api-ref/source/parameters.yaml
+++ b/placement-api-ref/source/parameters.yaml
@@ -11,6 +11,14 @@ resource_class_path: &resource_class_path
   required: true
   description: >
     The name of one resource class.
+resource_class_path_custom: &resource_class_path_custom
+  type: string
+  in: path
+  required: true
+  description: >
+    The name of one resource class. The name must start with
+    the prefix ``CUSTOM_``. If not, the request returns a ``Bad Request (400)``
+    response code.
 resource_provider_uuid_path: &resource_provider_uuid_path
   type: string
   in: path
@@ -221,6 +229,9 @@ reserved_opt:
 resource_class:
   <<: *resource_class_path
   in: body
+resource_class_custom:
+  <<: *resource_class_path_custom
+  in: body
 resource_class_links:
   type: array
   in: body
diff --git a/placement-api-ref/source/resource_class.inc b/placement-api-ref/source/resource_class.inc
index 5c84610e0ed3..61bb933f0cd2 100644
--- a/placement-api-ref/source/resource_class.inc
+++ b/placement-api-ref/source/resource_class.inc
@@ -64,7 +64,7 @@ Request
 
 .. rest_parameters:: parameters.yaml
 
-  - name: resource_class_path
+  - name: resource_class_path_custom
 
 Response
 --------
@@ -92,7 +92,8 @@ Request
 
 .. rest_parameters:: parameters.yaml
 
-  - name: resource_class
+  - name: resource_class_path
+  - name: resource_class_custom
 
 Request example
 ---------------
diff --git a/placement-api-ref/source/resource_classes.inc b/placement-api-ref/source/resource_classes.inc
index 256ea3557958..39289d0dda36 100644
--- a/placement-api-ref/source/resource_classes.inc
+++ b/placement-api-ref/source/resource_classes.inc
@@ -51,7 +51,7 @@ Request
 
 .. rest_parameters:: parameters.yaml
 
-  - name: resource_class
+  - name: resource_class_custom
 
 Request example
 ---------------