API allows you to create a value set with no codes associated with it.

[braydengramse]

Here is an example of the request that succeeds and probably shouldn't.
POST /valuesets
Request Payload:
{
"name":"Empty Value Set",
"versionDate":"2018-06-15T16:35:46.238Z",
"sourceDescription":"Population Builder",
"clientCode":"C00088",
"codeOperations":[
],
"authorityDescription":"Health Catalyst",
"definitionDescription":"This value set has no codes associated with it."
}