Improve error messages in middleware

**Feature request**
It would be great to have filtering for api.

**Use case**
Many users need this functionality for production deployments.

**Implementation idea**
Add a new config option `enable_filtering` with default `false`.

The issue names no files or tests; start by locating the middleware and configuration entry points related to the API. Clarify whether the intended change is API filtering or improved error messages, then verify that the selected behavior is controlled by enable_filtering with a default of false.

Written by the indexing model from the issue text.