By cancelled do you mean that when a deal is being deleted? If that's the case, currently the endpoint doesn't return deleted deal. Any deal that returned from deals API hasn't been deleted.
When looking to get notified of deleted deals, you can explore the HubSpot Webhook: Webhooks API Overview and subscribe to the deal deletions events.
When looking to retrieved deals that recently got updated/created, you can look into using this endpoint here: Get Recent Deals | Deals API so that you do not have to use the get all deals endpoint and page through all the deals.
thanks for your feedback. The endpoint you linked it's very good to understand the what is changed/created in last x time. How can I understand if something has been cancelled?
By cancelled do you mean that when a deal is being deleted? If that's the case, currently the endpoint doesn't return deleted deal. Any deal that returned from deals API hasn't been deleted.
When looking to get notified of deleted deals, you can explore the HubSpot Webhook: Webhooks API Overview and subscribe to the deal deletions events.