Can we have a `slave` tag that move to master in case of failure of a unique slave?

[lorello]

I've a mysql master-slave setup with 1 master and 1 slave. The application is configured to use master.mysql.service.consul (for INSERT/UPDATES) and slave.mysql.service.consul (for SELECT queries) to reach the respective mysql roles. This tools assign Master and Slave tags in an optimum way in normal conditions. But in case of failure of the slave I'd like to have that master and slave tags collapse on the same host, so that application continues to work without reconfiguration. Is it possible or I'm missing something on the use of tags with consul?