Handle edge cases in compression

**Problem**
When working with store, 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 in the issue. Start by locating the compression and store error-handling paths, then inspect existing tests or add focused coverage for the reported edge cases. Done means the relevant failures produce more descriptive error messages and the tests pass.

Written by the indexing model from the issue text.