Add TypeScript types for components

**Problem**
When working with helpers, 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 locate the components and helpers referenced by the title and inspect the existing error handling, then confirm the intended TypeScript type surface and message changes with maintainers. Done means the agreed types and error behavior are implemented and verified by the relevant project checks.

Written by the indexing model from the issue text.