If you want to include :[ in input source, you must escape it by using :[[ instead. The configuration generator replaces occurrences of :[[ with :[.
For example, to literally include the text :[box] without the provisioning system substituting a value for box, use :[[box].
When the input source is an attribute of a component that is authored in XML, the value is subject to the following rules for XML-based escape sequences:
To get the quote character (""), use the " sequence.
To get the apostrophe character ('), use the ' sequence.
To get the less-than character (<), use the < sequence.
To get the greater-than character (>), use the > sequence.
To get the ampersand character (&), use the & sequence.
These escape rules do not apply to override values input via the provisioning system's browser interface, configuration resource files, or input to the configuration generation CLI commands.