{
  "context": "This evaluation assesses how effectively the engineer uses Toil's CachingFileStore coordination capabilities for implementing worker failure detection and work redistribution. The criteria focus on correct usage of SQLite for shared state coordination, timestamp-based heartbeat tracking, and automatic work reassignment patterns.",
  "type": "weighted_checklist",
  "checklist": [
    {
      "name": "SQLite coordination setup",
      "description": "Uses SQLite database to maintain shared state between coordinator and workers. Creates appropriate schema with tables for worker registry (with worker_id, last_heartbeat timestamp, status) and work assignments (file_id, worker_id). Implements proper database connection management.",
      "max_score": 20
    },
    {
      "name": "Worker registration",
      "description": "Implements register_worker() method that correctly adds workers to the database with initial timestamp. Uses INSERT or INSERT OR REPLACE to handle registration. Properly initializes worker status as 'alive' or equivalent.",
      "max_score": 15
    },
    {
      "name": "Heartbeat recording",
      "description": "Implements record_heartbeat() method that updates worker's last-seen timestamp using time.time() or equivalent. Uses UPDATE statement to modify existing worker record. Ensures timestamp is stored as Unix timestamp (float) for comparison.",
      "max_score": 15
    },
    {
      "name": "Dead worker detection",
      "description": "Implements detect_dead_workers() method that queries database for workers whose last_heartbeat is older than (current_time - heartbeat_timeout). Returns list of dead worker IDs. Uses proper SQL comparison with time thresholds.",
      "max_score": 20
    },
    {
      "name": "Work assignment tracking",
      "description": "Implements assign_work() method that records file-to-worker assignments in database. Maintains relationship between file IDs and worker IDs for tracking. Implements get_worker_assignments() to query assignments by worker_id.",
      "max_score": 15
    },
    {
      "name": "Work redistribution",
      "description": "Implements redistribute_from_dead_worker() method that reassigns files from dead worker to target worker. Queries all files assigned to dead worker, updates their worker_id to target worker, and returns list of redistributed file IDs. Uses UPDATE or DELETE/INSERT operations.",
      "max_score": 15
    }
  ]
}