Regarding provisioning code:
I am not sure that every service provisioning scenario for every service provider would need such a provisioning code, so it is understandable why it is not in the model. And you could argue that the code is implied by the identity of the service specification.
But if it is needed, you could extend the model in your implementation of the API to add a provisioningCode attribute to ServiceSpecification. Or, you could make it part of catalog implementation, defining an invariant serviceSpecCharacteristic called provisioningCode and setting the serviceSpecCharacteristicValue to the code.
Regarding 3xx HTTP response codes, I have raised the issue informally in the Open API team, I cannot make any promises regarding potential fixes or enhancements.
Hope it helps
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Jonathan Goldberg
Amdocs Management Limited
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