Add rate limiting for filtering

**Description**
Currently utils lacks proper serialization support.

**Proposed solution**
Add configurable serialization with sensible defaults.

**Priority**: Low/Medium

Start by locating the utils code and the filtering path. The title requests rate limiting for filtering, while the description requests configurable serialization, so confirm the intended scope and expected behavior before identifying relevant entry points and tests.

Written by the indexing model from the issue text.