Firstly, insure your Mutiny system is running in secure mode (https) see; https://mutiny.freshdesk.com/support/solutions/articles/13000058555-web-server-settings
Download the agent from the download page; Mutiny-MSSQL-PerfCtr-Monitor-Setup.exe and install the new agent on your SQL server.
On your mutiny server find the node you wish to monitor.
Open the [agents] property page.
Select Agent API Tokens button
Choose Custom.
name your agent and apply
Copy the generated Token and paste it into the Mutiny Agent ID field on your agent.
Save the details and check for no error messages.