Special variables

Rhize designates some variable names for a special purpose in BPMN workflow. This list these special variables is as follows:

Variable	Purpose
`BODY`	The name of the variable as Input in Intermediate message throws. The value of this variable is the payload sent to the Rhize message broker.
`customResponse`	A value to report at the end of a synchronous API call to trigger a workflow. On completion, the call reports whatever the value was in the `customResponse` field of the GraphQL response. For details, read Trigger workflows.
`__traceDebug`	If `true` at the start of the workflow, the BPMN workflow reports the variable context at each node as spans in Tempo.