There is no official documentation. It all depends on the level of customization of your current Dynatrace environment. A lot of global settings can be migrated using the monaco tool quie teasily, but not all of them. Also, don't try to take a road to download and push the configuration - migrate it selectively.
For non-global configuration (such as setttings on a particular entity - for example anomaly detection settings), you can only set it in the UI or automate the UI actions.
With agents - you will need to reconfigure and restart them - that's probably the easiest part.
If you have the changes in your environment well documented, it will be almost a piece of cake. If not - the migration road can be challenging. But as with all migrations - take it as an opportunity to tidy up the environment 😀. Make a plan and take the gitops approach if possible. It will save you time in the future.
Even with the API, that would only be Global Settings, as @Julius_Loman stated, any adhoc config done to any service won't be able to export it via API, since is not possible to set the scope entity.
I think that the ability to do that change via API is one of the most frequent RFE i see from time to time.
There are so many settings that can be done manually on the entity level right now, so it's impossible to transfer the settings until Dynatrace provides you with the ability to use the API, or with some export/import. It's not only anomaly detection.
Request naming rules (on service entity) are just another typical example that is likely to be configured on your services but cannot be exported right now. Only global rules, which are not that widely used.
I really hope this will be addressed within one year in the product. Because right now, it's sometimes hard to just copy a subset of settings between environments. Monaco can save you a lot of manual work or scripting anyway.
I've marked our two earlier comments as correct solutions to keep this thread on topic. See below link where you may comment for the APIs.
You may be keen to vote on my product idea from a couple months back.
RFE: REST API to support all possible UI settings (implement monitoring-as-code solutions)
Since this has been asked a few times before, I will link you to one of the other answers provided recently:
The key point being that there's a few resources available already, like Julius mentioned, the Monaco project, which is also used internally by Dynatrace.
If you need help with it, I'd suggest connecting with a Dynatrace ONE Product Specialist , and they could also get you in contact with Dynatrace ACE Services to better assist you with the project specific requirements.