Improve error messages in utils

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

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

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

The issue does not name a file, test, or entry point. Start by locating the utility code that handles validation and error messages, then review how those errors are surfaced. Done means the relevant validation failures provide more descriptive messages, with the expected wording and coverage clarified before implementation.

Written by the indexing model from the issue text.