curl -i -X POST "https://api.box.com/2.0/hub_collaborations" \
     -H "box-version: 2025.0" \
     -H "authorization: Bearer <ACCESS_TOKEN>" \
     -H "content-type: application/json" \
     -d '{
       "hub": {
         "type": "hubs",
         "id": "42037322"
       },
       "accessible_by": {
         "type": "user",
         "id": "23522323"
       },
       "role": "viewer"
     }'

{
  "id": "12345678",
  "type": "hub_collaboration",
  "hub": {
    "id": "12345",
    "type": "hubs"
  },
  "accessible_by": {
    "id": "11446498",
    "type": "user",
    "name": "Aaron Levie",
    "login": "ceo@example.com"
  },
  "role": "editor",
  "status": "accepted",
  "acceptance_requirements_status": {
    "terms_of_service_requirement": {
      "is_accepted": true,
      "terms_of_service": {
        "id": "11446498",
        "type": "terms_of_service"
      }
    },
    "strong_password_requirement": {
      "enterprise_has_strong_password_required_for_external_users": true,
      "user_has_strong_password": true
    },
    "two_factor_authentication_requirement": {
      "enterprise_has_two_factor_auth_enabled": true,
      "user_has_two_factor_authentication_enabled": true
    }
  }
}