Creates a new Variable for the Tenant, for use as a field engine_name in Page submit or elsewhere.

Environment. A live_ key creates the variable in Production. Any other key, such as a test_ key, creates it in Sandbox. engine_name must be unique within that environment only, so the same engine_name can exist once in Production and once in Sandbox.

⚠️ Only types 1 (numeric), 2 (string), 3 (boolean) and 6 (list) can be created through this endpoint. Any other type, such as 5 (date), returns a 400.