Add rate limiting for serialization

**Problem**
When working with middleware, the error messages could be more descriptive.

**Suggestion**
Improve error handling and add detailed error messages.

**Context**
This would help with debugging and maintenance.

Start by tracing the middleware and serialization entry points named in the issue; the payload does not identify specific files or tests. Clarify the rate-limiting scope, expected error messages, and completion criteria before making changes.

Written by the indexing model from the issue text.