Improve error messages in config

**Problem**
When working with data, 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 names configuration error handling but provides no file, entry point, failing case, or test. Start by locating the config-related error paths in the repository and identify which cases need more detail; done means those errors provide descriptive messages and the relevant checks pass.

Written by the indexing model from the issue text.