Confirmed current behavior
Collection creation is gated above the free plan. That behavior is implemented directly in the collections API. On the free tier, the API returns a structuredforbidden response with a LIMIT_COLLECTIONS code and an upgrade_plan upgrade target.
Other usage-sensitive areas
The product also enforces or tracks usage around areas such as:- sources
- concurrent runs
- crawled pages
- converted files
- indexed pages
- API calls