In general, if I can do something via the Web UI, should I expect to be able to also do that via the Json API?
For example, in the Web UI, it is easy to create a secondary email for a contact, and to switch which email is the primary. Despite much searching, I cannot find out how to do that via the Json API.
To me, there are two aspects to this question: On the one hand, this is a very specific question regarding a specific functionality that you're able to use in-app that you are not able to use via the API. On the other hand, it's a bit of a philosophical question about HubSpot's API design. I'll try to touch on both of these points separately in my thoughts below:
Regarding the ability to add secondary emails:
This is something that you can do with ease in-app, but cannot do via the API. The fact that this functionality doesn't currently exist isn't necessarily an intentional design choice by the HubSpot product team; it's just not something that the team has built. For functionality requests like this, the best place to provide give feedback is the HubSpot Community.
Regarding the question on in-app <-> API feature parity:
I would say that it is not accurate to say that if something is possible in-app, it should also be possible via the API. There are some things that HubSpot intentionally does not allow via the API; one example of this is the Sequences tool. It's simple to enroll a contact in a sequence in-app, but there isn't a Sequences API (and there likely never will be). This is because the Sequences tool is not intended to be used to automate bulk communications, and the ability to programmatically enroll contacts in sequences would run counter to that goal.
Does that help answer your question? I'm happy to continue the discussion here or help answer other questions you might have!
In integrating with Hubspot's API, the main questions I'm asking myself are, "What can the API do? How does it do it?" which are sub-questions of the more general, "How do we leverage Hubspot API to support business goals?"
When you discover that Hubspot nearly does what you need - but not quite - then you start looking for workarounds, start exploring possibilities.
And that's when I find myself asking X-Y questions.
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