tagKeyBoundaries

Enter the existing custom tag keys for custom applications in your system. Resource tags help Amazon Q narrow the search space when it is unable to discover definite relationships between resources. For example, to discover that an Amazon ECS service depends on an Amazon RDS database, Amazon Q can discover this relationship using data sources such as X-Ray and CloudWatch Application Signals. However, if you haven't deployed these features, Amazon Q will attempt to identify possible relationships. Tag boundaries can be used to narrow the resources that will be discovered by Amazon Q in these cases.

You don't need to enter tags created by myApplications or CloudFormation, because Amazon Q can automatically detect those tags.