While we provide copies of the documentation for the R80.x Management APIs online, sometimes you don't have Internet access.
Or, like in the case of the R80.20 EA, we haven't published them publicly yet
Turns out, we make this available on the management server using via the following URL:
https://management-ip/api_docs
This will give you the version of the API that is supported on your management specifically (versus the above link, which points to the latest).
For this trick to work, the Web API must be accessible from your IP address.
Otherwise, you will get a 403 Forbidden message from Apache.
The API can be enabled from the CLI using something like:
mgmt_cli -r true --domain MDS set api-settings accepted-api-calls-from "All IP addresses"
Or from SmartConsole:
Then you will need to restart the API server from the CLI for the change to take effect.
api restart
See also: Check Point - Management API reference
And, of course, thanks to Tomer Sole for sharing this tip with me.