There's no rate for User Actions with errors. I will put this on the backlog and maybe we will add it.
In addition to the request rate, there's there are several options:
My answer is not very specific. Please let me know which options sound good for you and maybe even a bit more background on what you a looking for and I will follow-up with more detailed information.
Regarding the options that I've listed above, most of them will require you to do the actual charting outside of Dynatrace.
But we have an upcoming feature, that will be released early next year: SLI and SLO.
This will allow you to create an SLI for 'healthy' User Actions, by comparing the count for the Custom Metric that you create for 'healthy' User Actions against the total count of User Actions for your app.
Once the SLI has been created, it will have an error budget and warning state and it can be added to a dashboard.
This is probably what you are looking for
a note: it's not totally straightforward, since the Custom Metric that can be created via the MDA (see below), will measure duration and here the count is needed. This can be achieved by appending `:(count)` to the key of the metric when defining the SLI.
on creating a Custom Metric:
The way to go is to create a custom metric for "healthy" User Actions. i.e. in the MDA you need to filter for user actions that have no error and press "Create Metric".
That provides you with a metric for the total count and a metric for the "healthy" count.
To chart that in an external tool, you can access these metrics via API (in the upper right corner press on the user icon look for "Environment API v2" in the menu that opens; on that API documentation page look for "Metrics").
Hey! In the meantime, we have released a new feature 'SLO' which allows you to compare two metrics to calculate a success rate.
With this you could e.g. use the Apdex to measure total number of user actions against the number of frustrated user actions.