HubSpot's Contacts API is powerful, but it comes bolted to a full CRM: object schemas, associations, deal pipelines, OAuth apps, and rate tiers you have to reason about before you can store a single email. If all you need is to save contacts and read them back, that's a lot of surface area.
When to look elsewhere
- You want a plain
POST /contacts, not a CRM object model. - You don't need deals, tickets, or marketing automation.
- You'd rather not manage a HubSpot app and OAuth scopes for a side project.
Alternatives worth considering
- ContactAPI: open-source REST CRUD, upsert by email, publishable keys for the browser.
- Airtable: good if you also want a spreadsheet UI for non-developers.
- A Postgres table plus your own endpoints: most control, most maintenance.
Keep HubSpot if you genuinely need the CRM: sales pipelines, email sequences, and reporting across a team. Drop it when the CRM is dead weight around a contacts table.
Where ContactAPI fits
ContactAPI is an open-source REST API for saving and managing contacts. You POST an email plus any JSON fields, get simple CRUD back, and can reach the same data from an AI client over its MCP server. No CRM, no pipeline stages, no lock-in.