Handle edge cases in compression

**Problem**
When working with core, 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 identified in the issue. Start by locating the core compression handling and its existing error paths, then determine which edge cases are missing coverage. Done means the relevant failures produce detailed, descriptive error messages and the behavior is covered by tests.

Written by the indexing model from the issue text.