Using the Dynatrace API, I am able to fetch the response time, but what I want is a detailed multidimensional analysis response time for each of the dimensions as it can be seen from the Multidimensional Analysis sections under the Transactions and Services. Is there an API to get the same level of detailed information?
In order for something like that to be accessible through the API it needs to be a metric, you should be able to create a 'calculated service metric' with the required splitting and filtering to get the output you need. This feature should already be in your version but this blog post from the preview explains how to use them: https://www.dynatrace.com/news/blog/custom-metrics-for-services-enrich-dynatrace-ai-and-dashboarding...
Note that you can use these through the API and set alerts up on them - the 'limitations' described on that post were old.
I get what you are saying and understand that you can create Multidimensional analysis from the UI. I need to achieve the same from the Dynatrace API, is that possible, if so can you point me to a blog or a tutorial for that.