Update routes documentation

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

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

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

Start by locating the route and controller handling mentioned in the issue and read the existing error paths and related tests, if present. Clarify whether the intended work is route documentation, controller error handling, or both; done should mean the agreed scope is implemented with detailed error messages and any requested documentation updated.

Written by the indexing model from the issue text.