Handle edge cases in sorting

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

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

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

No file, test, or entry point is named. Start by locating the sorting and API error-handling entry points and their existing tests; clarify which edge cases and message details are required before making changes. Done means the agreed sorting cases are handled and the resulting API errors are more descriptive, with tests covering them.

Written by the indexing model from the issue text.