Add configuration options for search

**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.

The issue names no files, tests, or entry points. Start by clarifying which controller search behavior needs configuration and which error cases need detail; done should be defined by documented options and verifiable error-message behavior.

Written by the indexing model from the issue text.