System-generated Variables
Besides the variables that commands create, the variable context can contain different automatically generated variables. Unless otherwise noted, all these variables are available right from the start of any evaluation process. Note that while being system-generated, these variables' values are not protected from being overwritten by commands, so it would be a good idea to not use any of these variable names as the var value of a command.
error
The variable named "error" is generated only when a command error occurs on a Step with an error-handling route defined. It holds a Map containing the following entries:
commandName - A String that is the name of the command that generated the error.
message - A String that is the error message produced by the command.
param
The variable named "param" holds a Map that contains all the parameters included in the HTTP request initiating the Flow evaluation process. It is accessed in numerous templates' logic, usually at the very start by some command using the expression "${param.id}" as the "id" parameter typically holds the ID of the Salesforce record that is to be the "main record" of the evaluation. Besides user-provided request parameters, the system internally adds certain request parameters as well. Of these the following entries may be of use:
templateId - A String that is the ID of the ContentDocument record representing the currently running template.
eventID - A String that is the Event value given to the Flow that affects the starting Step of every Segment.
button - A String that is the name of the submit button that was pressed to exit the previous Screen. This entry will not exist before a Screen step has been evaluated during the evaluation process.
sfdcServer
The variable named "sfdcServer" holds a String that is the URL of the Salesforce server Dynamo connected to with the credentials of the user currently running the Flow.
UserInfo
The variable named "UserInfo" holds the sole UserInfo value of any evaluation process. This value contains data that Salesforce tells of the user currently running the Flow, such as id, full name, email address, profile and such.