Support notifications configuration

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

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

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

The issue names no files, tests, or entry points. First clarify whether the intended work is notification configuration or more descriptive model errors, then identify the relevant CLI and model error-handling paths; done should include a specific configuration behavior and corresponding verification.

Written by the indexing model from the issue text.