Search the currently visible tool list by name and description.

Use this only when you are unsure which existing tool fits a task. It returns tools that are
already available to you under the current runtime and permission profile — it does NOT load,
unlock, or reveal any hidden tools. Everything it can return is already callable directly, so
prefer calling the tool you need over searching for it; searching does not make any new tool
available.

Provide concise keywords such as `worktree`, `background task`, `read file`, or `web search`.
