In the Admin UI under the extend menu there is a HEAT API section with the documentation you require.
Under the Integration Tools Menu there is also a section where you can add Web Service Integration Scripts. There are a number of out of he box examples you can review e.g. Exchange calendar Integration.
I'm not clear on this... Do you mean log in as admin (done). Then I look for an object called "extend" I don't see anything. Can you upload a screenshot.
There is no object you need to open the AdminUI (Configure Application) top right hand side of ISM.
Then in the left hand menu of the AdminUI select HEAT API or HEAT REST from the Extend Menu
Here are the links to the help documentation for the Web API, the REST API documentation is under the HEAT API menu option in the picture above.
I hope this helps.
I have a related question, I can't seem to access the ../ServiceAPI/FRSHEATIntegration.asmx page, is there settings I need to configure on IIS or in Admin?
I get "You do not have permission to view this directory or page."
you probably experience a bug in Heat I reported some time ago. When I try to access the web service endpoints using a FQDN I get this error, using just the hostname works.
In short: something like http://hostname/HEAT/ServiceAPI/FRSHEATIntegration.asmx does work, but http://hostname.subdomain.domain/HEAT/ServiceAPI/FRSHEATIntegration.asmx does not, throwing the exception as above.
Requesting the wsdl document works for both hostname and FQDN.