Add rate limiting for retry

**Problem**
When working with core, 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 file, test, or entry point. Start by locating the retry handling in the terminal agent, then determine how rate limiting should interact with retries and add coverage showing that retry attempts are bounded; done means descriptive errors and the agreed limit are verified.

Written by the indexing model from the issue text.