JSON string with filter criteria, e.g., {"title": "specific title", "description": "description text", "urgency": "A", "source": "AI_GENERATED", "status": "OPEN", "type": "AUDIT", "assignee": "John Smith", "assigneeUserId": "user-123", "impactAreaId": "area-456", "dueDateFrom": "2024-01-01", "dueDateTo": "2024-12-31", "isOverdue": true}. The assignee field accepts user names or email addresses for text search, while assigneeUserId is for exact user ID matching.