Optimize helpers for large datasets

**Problem**
When working with handlers, 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 locating the handler and helper code responsible for the current error messages. Review how errors are produced for large datasets and determine which additional context is needed. Done means the relevant failures produce more descriptive messages and the behavior is covered by the project's existing checks.

Written by the indexing model from the issue text.