Dynamically add labels in a Counter or CounterVec

[nevesgustavo]

Hi Team,
I hope you are having a good weekend, I would like to have an information about CounterVec, is there a way to dynamically add Labels inside an already registered metric?

For example:

Creating a metric using two labels: status and environment

metricName := "test_purposes"
help := "tests"

counter = promauto.NewCounterVec(prometheus.CounterOpts{
		Name: metricName,
		Help: help,
	}, []string{"status", "environment"})

	counter.WithLabelValues("success", "dev").Inc()

But when the status is error I would like to add one more label: reason, to the same metric and it's not possible

counter = promauto.NewCounterVec(prometheus.CounterOpts{
		Name: metricName,
		Help: help,
	}, []string{"status", "environment", "reason"})

	counter.WithLabelValues("success", "dev", "npe").Inc()

Just to explain why I need it, we're migrating an implementation of datadog to prometheus and in the implementations based on datadog we have a lot of microservices sending metrics using different tags (labels) to the same metric, if I could do the same using the prometheus lib it would be great because we could only change the client without any modifications on metric publishers.