My application tries to get the list of Planner Tasks via plan Id and with filtering, something like this:
v1.0/planner/plans/{plan-id}/tasks?$filter=contains(title, 'sample')
/v1.0/planner/plans/{plan-id}/tasks?$filter=dueDateTime ge 2025-07-03T21:00:00.000Z and dueDateTime le 2025-07-16T20:59:59.999Z
Microsoft Graph Planner API does not return error but seems it completely ignores $filter parameter and returns whole list.
How to execute query with filtering?
The /tasks endpoint does not support $filter. Not all Graph endpoints support OData query parameters, and those that do typically only support a subset of them.
Barring a few exceptions where the docs have not been updated, if a Graph endpoint supports query parameters for a given operation, those parameters will be outlines in the Optional query parameters section of the operation (e.g. List Users).