There is no mechanism for obtaining the release name via the API. With most services you can find information about supported API versions by querying the top-level URL for the endpoint. For example, if I query the glance endpoint:
$ curl http://localhost:9292/
{"versions": [{"status": "CURRENT", "id": "v2.2", "links": [{"href": "http://localhost:9292/v2/", "rel": "self"}]}, {"status": "SUPPORTED", "id": "v2.1", "links": [{"href": "http://localhost:9292/v2/", "rel": "self"}]}, {"status": "SUPPORTED", "id": "v2.0", "links": [{"href": "http://localhost:9292/v2/", "rel": "self"}]}, {"status": "CURRENT", "id": "v1.1", "links": [{"href": "http://localhost:9292/v1/", "rel": "self"}]}, {"status": "SUPPORTED", "id": "v1.0", "links": [{"href": "http://localhost:9292/v1/", "rel": "self"}]}]}
And of course you can get a list of available services by querying Keystone for the service catalog.
There is no concept of a "cloud identifier". Individual clouds are identified by API endpoints. Generally, each OpenStack cloud will have a unique Keystone authentication URL, and I guess you could treat this as an identifier.