It looks like some changes have been made to the underlying library that aren't reflected in the README, e.g., mergeclient.ClientWithAuthApiKey() is mentioned but does not seem to exist, though mergeclient.WithApiKey() does.
Also, the Go version and gopkg.in/yaml.v3 are 5-years-old and 5-years-unmaintained, respectively. It would be nice to get a refresh of at least the yaml package to something maintained, e.g., goccy/go-yaml. (maybe testify just to keep up)
Thanks!