role_name

src/azure-cli/azure/cli/command_modules/role/_params.py

@@ -372,4 +372,5 @@ class PrincipalType(str, Enum):
         c.argument('role_definition_id', options_list=['--name', '-n'], help='the role definition name')
         c.argument('custom_role_only', arg_type=get_three_state_flag(), help='custom roles only(vs. build-in ones)')
         c.argument('role_definition', help="json formatted content which defines the new role.")
-        c.argument('name', arg_type=name_arg_type, completer=get_role_definition_name_completion_list, help="the role's name")
+        c.argument('name', arg_type=name_arg_type, completer=get_role_definition_name_completion_list,
+                   help="Matches the role definition's name (GUID) or roleName (e.g. 'Reader') property.")

src/azure-cli/azure/cli/command_modules/role/custom.py

@@ -141,7 +141,11 @@ def delete_role_definition(cmd, name, resource_group_name=None, scope=None,
 
 def _search_role_definitions(cli_ctx, definitions_client, name, scopes, custom_role_only=False):
     for scope in scopes:
-        roles = list(definitions_client.list(scope))
+        # name argument can match either name (GUID) or roleName (e.g. 'Reader') property.
+        # Only roleName can be used as a filter in Role Definitions - List API.
+        # If name is a GUID, the filtering is performed on the client side.
+        filter_query = f"roleName eq '{name}'" if name and not is_guid(name) else None
+        roles = list(definitions_client.list(scope, filter=filter_query))
         worker = MultiAPIAdaptor(cli_ctx)
         if name:
             roles = [r for r in roles if r.name == name or worker.get_role_property(r, 'role_name') == name]