MQTTController 23135 In action payload, force conversion of all data types to string for "raw" output, rather than assuming result of expression is a string (although docs say to do that, it's just too easy to omit, and too easy to change it so the requirement is moot). Add parameter: name value form to action payload definition to draw payload value from the named parameter without the need to use an expression (this follows the implementation of action definitions in other Controller instances as well). That is, you can specify, for example, parameter: level instead of using expr: parameters.level (assuming the parameter value requires no scaling or other modifications to be compatible with the device). [docs]