Update types documentation

**Problem**
When working with types, 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. Start by locating the type-related error handling in the repository, then clarify which errors and message details are in scope; done should include agreed descriptive messages and tests or documentation covering them.

Written by the indexing model from the issue text.