□ Where are permission checks implemented?
  - Decorators? (@login_required, @permission_required, custom?)
  - Middleware? (TenantMiddleware, AuthorizationMiddleware?)
  - Base classes? (BaseAPIView, TenantScopedViewSet?)
  - Permission classes? (DRF permission_classes?)
  - Custom mixins? (OwnershipMixin, TenantMixin?)

□ How are queries scoped?
  - Custom managers? (TenantManager, UserScopedManager?)
  - get_queryset() overrides?
  - Middleware that sets query context?

□ What's the ownership model?
  - Single user ownership? (document.owner_id)
  - Organization/tenant ownership? (document.organization_id)
  - Hierarchical? (org -> team -> user -> resource)
  - Role-based within context? (org admin vs member)

# Find how auth is typically done
grep -rn "permission_classes\|@login_required\|@permission_required" --include="*.py" | head -20

# Find base classes that views inherit from
grep -rn "class Base.*View\|class.*Mixin.*:" --include="*.py" | head -20

# Find custom managers
grep -rn "class.*Manager\|def get_queryset" --include="*.py" | head -20

# Find ownership fields on models
grep -rn "owner\|user_id\|organization\|tenant" --include="models.py" | head -30

□ What models contain user data?
□ Which have ownership fields (owner_id, user_id, organization_id)?
□ Which are accessed via ID in URLs or request bodies?

1. Where does the resource ID enter the system?
   - URL path: /api/documents/{id}/
   - Query param: ?document_id=123
   - Request body: {"document_id": 123}

2. Where is that ID used to fetch data?
   - Find the ORM query or database call

3. Between (1) and (2), what checks exist?
   - Is the query scoped to current user?
   - Is there an explicit ownership check?
   - Is there a permission check on the object?
   - Does a base class or mixin enforce access?

4. If you can't find a check, is there one you missed?
   - Check parent classes
   - Check middleware
   - Check managers
   - Check decorators at URL level

□ For list endpoints: Does the query filter to user's data, or return everything?

□ For create endpoints: Who sets the owner - the server or the request?

□ For bulk operations: Are they scoped to user's data?

□ For related resources: If I can access a document, can I access its comments?
  What if the document belongs to someone else?

□ For tenant/org resources: Can User in Org A access Org B's data by changing
  the org_id in the URL?