Add rate limiting for caching

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

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

**Priority**: Low/Medium

The issue names no files, tests, or entry points. First reconcile the title's rate-limiting request with the body’s serialization request, then locate the caching and type-handling code; done is a clearly scoped change with configurable serialization, sensible defaults, and any required rate-limiting behavior covered by tests.

Written by the indexing model from the issue text.