Nine things I measured about the HubSpot API that the docs don't tell you

I spent a day building a read-only tool that answers one question about a HubSpot portal: what is the cheapest tier its current usage actually requires?

Everything below was probed with GET requests against a live portal on 2 August 2026. Where it contradicts HubSpot's documentation, trust this. The tool is open source and MIT licensed: meticulosity/hubspot-license-fit.

1. The API cannot tell you what a portal is subscribed to

This is the constraint the whole design hangs off, so it is worth establishing first.

GET /account-info/v3/details