- Simplify list-all: normalize keywords to empty string early, remove list_all var
- Move helpers after usage (_is_uuid, _get_library_agent_by_id, _library_agent_to_info)
- Extract _library_agent_to_info to deduplicate AgentInfo construction
- Add NotFoundError catch in graph_id lookup path
- Differentiate suggestions for empty library vs no search results
- Make session_id optional, query not required
- Update tool description: 'Search for or list'