Management packs contain definitions of rules, monitors or composite module types where those monitoring objects need to be configured. In the configuration of the module type, in addition to providing constant values, you can also provide variable context parameter.
All Context parameters can be used in any part of a text and replaced by the runtime with the actual parameter value before the module is instantiated. Context parameters are specified within “$” delimiter in a text. If you want to escape the delimiter, you can use “$$”.