You specify stack tags with the
tags property. CloudFormation automatically adds the tags to each resource in the stack that supports tagging.
tags:foo: barcode: 123backups: true
tags property can be defined in stack and stack group configuration files. If specified in a stack group, the stack group's children and stacks inherit the value. Stack groups and stacks can add new tags and overwrite individual tags they inherited from their parent by specifying a new value with the same key.
tags property must satisfy these requirements:
Each tag key must be a string
Each tag value must be a string, a number or a boolean