Handle edge cases in caching

**Problem**
When working with auth, 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 authentication error-handling and caching paths in the repository, since the issue does not name specific files or tests. Determine which auth failures currently produce insufficient messages, then verify that the resulting errors provide more detail useful for debugging and maintenance.

Written by the indexing model from the issue text.