Optimize helpers for large datasets

**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 does not name any files, tests, or entry points. Start by locating the type-related error handling in the terminal agent, then review the existing messages and identify which type details are missing. Done means the relevant errors provide more descriptive messages and the affected error paths are verified.

Written by the indexing model from the issue text.