Improve error messages in store

**Problem**
When working with utils, 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 store and utils entry points in the repository, then trace where their current errors are created or surfaced. Review any existing tests around those paths and define the expected detailed messages before changing behavior. Done means failures in the affected store utilities provide more descriptive errors and the relevant tests pass.

Written by the indexing model from the issue text.